Comprehensive Physiology Wiley Online Library

Lung Mechanics in Disease

Full Article on Wiley Online Library



Abstract

The sections in this article are:

1 Obstructive Lung Disease
1.1 Chronic Obstructive Pulmonary Disease
1.2 Asthma
1.3 Upper Airway Obstruction
2 Restrictive Lung Disease
2.1 Intrapulmonary Disease
2.2 Extrapulmonary Disease
Figure 1. Figure 1.

Normal, restrictive, and obstructive patterns on forced expiratory spirogram.

Figure 2. Figure 2.

Representative maximum flow‐volume loops of various forms of obstructive lung disease compared with normal. Volume given as % vital capacity (VC) exhaled from total lung capacity (TLC). Ratio of maximum expiratory flow/maximum inspiratory flow at 50% VC (mid‐VC flow ratio) shown for each loop. V, flow.

From Miller and Hyatt
Figure 3. Figure 3.

Different mechanisms of reduction in conductance in chronic obstructive pulmonary disease (COPD). At a given lung volume, conductance is reduced both with loss of lung recoil pressure (solid lines) and with intrinsic airway disease (broken lines), but when loss of lung recoil pressure is the only abnormality the conductance‐static transpulmonary pressure curve may lie in normal range (stippled area).

Figure 4. Figure 4.

Schematic isovolume pressure‐flow (IVPF) curves at 50% VC for normal subject and patient with airflow limitation. Compared with normal subject, in airflow limitation, lung conductance (barfilled circlebar), the lowest pleural pressure (Ppl) at which maximum flow is achieved (open circles), maximum expiratory flow (bars), and lung recoil pressure (indicated by distance from filled circle to zero Ppl) are all reduced. VE, expiratory flow; VI, inspiratory flow.

Figure 5. Figure 5.

Representative static expiratory pressure‐volume curves of lungs in subjects with severe emphysema and severe pulmonary fibrosis, compared with normal subject. Lung volume (VL) measured by body plethysmography. PL, transpulmonary pressure. Solid lines through experimental points were derived by exponential curve‐fitting procedure. Broken lines, extrapolation of curve to infinite pressure and to volume axis at zero pressure. Values of k (cmH2O−1): for emphysema, 0.325; normal, 0.143; fibrosis, 0.089.

Adapted from Gibson, Pride, et al.
Figure 6. Figure 6.

Maximum expiratory flow‐volume curves compared with tidal flow‐volume curve during quiet breathing in normal subject (left) and patient with severe airflow limitation (right). In patient, tidal expiratory flow reaches maximum levels. Expiratory flow () in liters per second (LPS); VL, lung volume; VT, tidal volume; TLC, total lung capacity; FRC, functional residual capacity; RV, residual volume; VC, vital capacity.

From Bates, Macklem, and Christie
Figure 7. Figure 7.

Modified Campbell diagram showing relation between inspiratory pleural pressure during tidal breathing and during maximum inspiratory efforts (Ppl min) for a normal subject. During tidal breathing at FRC, inspiratory pleural pressure is reduced to overcome elastic recoil pressure of chest wall (Pel,w) and lungs (Pel,L) (hatched area E) and airflow resistance (hatched area R). Functional residual capacity (FRC) is volume at which ‐Pel,L line meets Pel,w line. If normal subject breathes with similar tidal volume at an increased end‐expired volume, elastic work is greatly increased and tidal inspiratory pleural pressures are an increased proportion of inspiratory pressure capacity (horizontal distance between Pel,w and Ppl min lines).

Figure 8. Figure 8.

Characteristic changes in maximum expiratory flow‐volume (MEFV) curve as asthma becomes more severe. All changes referred to curve in remission of asthma (top curve). Triangles, peak expiratory flow (PEF); squares, maximum flow at 50% VC (max50); circles, maximum flow when 25% VC remains to be expired (max25). Note progressive convexity of curve toward volume axis as airflow limitation worsens. Because of reduction in VC, max50, and max25 are measured at successively larger volumes as airflow limitation worsens. With mild limitation, largest proportional changes are in max25 and max50 rather than PEF or VC.

Figure 9. Figure 9.

Representative maximum expiratory flow‐volume curves while breathing air (broken lines) and He‐O2 mixture (solid lines) for normal subject, patient with COPD (irreversible airway obstruction), and asthmatic subjects with (responder) and without (nonresponder) density dependence of maximum flow (Vmax). Pulmonary resistance (RL) in cmH2O‐liter−1 s indicated (air → He‐O2) for each subject. Volume measured with subject in body plethysmograph and expressed as percent of VC remaining to be expired.

Adapted from Despas, Leroux, and Macklem
Figure 10. Figure 10.

Mechanisms of restrictive lung disease. In practice when reduced lung expansion is chronic it is usually accompanied by reduced compliance (displacement of pressure‐volume curve to right). PL, transpulmonary pressure; TLC, total lung capacity.

Figure 11. Figure 11.

Relation between respiratory muscle strength and vital capacity in 25 patients with chronic neuromuscular disorders. Respiratory muscle strength calculated from average of inspiratory and expiratory pressures during maximum efforts. Solid curve, theoretical effect of respiratory muscle weakness (with proportionate effects on expiratory and inspiratory muscles) on vital capacity assuming normal respiratory system recoil pressures.

Adapted from De Troyer et al.


Figure 1.

Normal, restrictive, and obstructive patterns on forced expiratory spirogram.



Figure 2.

Representative maximum flow‐volume loops of various forms of obstructive lung disease compared with normal. Volume given as % vital capacity (VC) exhaled from total lung capacity (TLC). Ratio of maximum expiratory flow/maximum inspiratory flow at 50% VC (mid‐VC flow ratio) shown for each loop. V, flow.

From Miller and Hyatt


Figure 3.

Different mechanisms of reduction in conductance in chronic obstructive pulmonary disease (COPD). At a given lung volume, conductance is reduced both with loss of lung recoil pressure (solid lines) and with intrinsic airway disease (broken lines), but when loss of lung recoil pressure is the only abnormality the conductance‐static transpulmonary pressure curve may lie in normal range (stippled area).



Figure 4.

Schematic isovolume pressure‐flow (IVPF) curves at 50% VC for normal subject and patient with airflow limitation. Compared with normal subject, in airflow limitation, lung conductance (barfilled circlebar), the lowest pleural pressure (Ppl) at which maximum flow is achieved (open circles), maximum expiratory flow (bars), and lung recoil pressure (indicated by distance from filled circle to zero Ppl) are all reduced. VE, expiratory flow; VI, inspiratory flow.



Figure 5.

Representative static expiratory pressure‐volume curves of lungs in subjects with severe emphysema and severe pulmonary fibrosis, compared with normal subject. Lung volume (VL) measured by body plethysmography. PL, transpulmonary pressure. Solid lines through experimental points were derived by exponential curve‐fitting procedure. Broken lines, extrapolation of curve to infinite pressure and to volume axis at zero pressure. Values of k (cmH2O−1): for emphysema, 0.325; normal, 0.143; fibrosis, 0.089.

Adapted from Gibson, Pride, et al.


Figure 6.

Maximum expiratory flow‐volume curves compared with tidal flow‐volume curve during quiet breathing in normal subject (left) and patient with severe airflow limitation (right). In patient, tidal expiratory flow reaches maximum levels. Expiratory flow () in liters per second (LPS); VL, lung volume; VT, tidal volume; TLC, total lung capacity; FRC, functional residual capacity; RV, residual volume; VC, vital capacity.

From Bates, Macklem, and Christie


Figure 7.

Modified Campbell diagram showing relation between inspiratory pleural pressure during tidal breathing and during maximum inspiratory efforts (Ppl min) for a normal subject. During tidal breathing at FRC, inspiratory pleural pressure is reduced to overcome elastic recoil pressure of chest wall (Pel,w) and lungs (Pel,L) (hatched area E) and airflow resistance (hatched area R). Functional residual capacity (FRC) is volume at which ‐Pel,L line meets Pel,w line. If normal subject breathes with similar tidal volume at an increased end‐expired volume, elastic work is greatly increased and tidal inspiratory pleural pressures are an increased proportion of inspiratory pressure capacity (horizontal distance between Pel,w and Ppl min lines).



Figure 8.

Characteristic changes in maximum expiratory flow‐volume (MEFV) curve as asthma becomes more severe. All changes referred to curve in remission of asthma (top curve). Triangles, peak expiratory flow (PEF); squares, maximum flow at 50% VC (max50); circles, maximum flow when 25% VC remains to be expired (max25). Note progressive convexity of curve toward volume axis as airflow limitation worsens. Because of reduction in VC, max50, and max25 are measured at successively larger volumes as airflow limitation worsens. With mild limitation, largest proportional changes are in max25 and max50 rather than PEF or VC.



Figure 9.

Representative maximum expiratory flow‐volume curves while breathing air (broken lines) and He‐O2 mixture (solid lines) for normal subject, patient with COPD (irreversible airway obstruction), and asthmatic subjects with (responder) and without (nonresponder) density dependence of maximum flow (Vmax). Pulmonary resistance (RL) in cmH2O‐liter−1 s indicated (air → He‐O2) for each subject. Volume measured with subject in body plethysmograph and expressed as percent of VC remaining to be expired.

Adapted from Despas, Leroux, and Macklem


Figure 10.

Mechanisms of restrictive lung disease. In practice when reduced lung expansion is chronic it is usually accompanied by reduced compliance (displacement of pressure‐volume curve to right). PL, transpulmonary pressure; TLC, total lung capacity.



Figure 11.

Relation between respiratory muscle strength and vital capacity in 25 patients with chronic neuromuscular disorders. Respiratory muscle strength calculated from average of inspiratory and expiratory pressures during maximum efforts. Solid curve, theoretical effect of respiratory muscle weakness (with proportionate effects on expiratory and inspiratory muscles) on vital capacity assuming normal respiratory system recoil pressures.

Adapted from De Troyer et al.
References
 1. Anthonisen, N. R., J. Danson, P. C. Robertson, and W. R. D. Ross. Airway closure as a function of age. Respir. Physiol. 8: 58–65, 1969.
 2. Antic, R., and P. T. Macklem. The influence of clinical factors on site of airway obstruction in asthma. Am. Rev. Respir. Dis. 114: 851–859, 1976.
 3. Arora, N. S., and D. F. Rochester. Effect of body weight and muscularity on human diaphragm muscle mass, thickness, and area. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 64–70, 1982.
 4. Ashutosh, K., R. Gilbert, J. H. Auchincloss, Jr., and D. Peppi. Asynchronous breathing movements in patients with chronic obstructive pulmonary disease. Chest 67: 553–557, 1975.
 5. Astin, T. W., and R. W. B. Penman. Airway obstruction due to hypoxemia in patients with chronic lung disease. Am. Rev. Respir. Dis. 95: 567–575, 1967.
 6. Bachofen, H., and M. Scherrer. Lung tissue resistance in healthy subjects and in patients with lung disease. In: Airway Dynamics, edited by A. Bouhuys. Springfield, IL: Thomas, 1970, p. 123–134.
 7. Baldwin, E. de F., A. Cournand, and D. W. Richards, Jr. Pulmonary insufficiency. III. A study of 122 cases of chronic pulmonary emphysema. Medicine Baltimore 28: 201–237, 1949.
 8. Baldwin, E. deF., K. A. Harden, D. G. Greene, A. Cournand, and D. W. Richards. Pulmonary insufficiency. IV. A study of 16 cases of large pulmonary air cysts and bullae. Medicine Baltimore 29: 169–194, 1950.
 9. Barnett, T. B. Effects of helium and oxygen mixtures on pulmonary mechanics during airway constriction. J. Appl. Physiol. 22: 707–713, 1967.
 10. Bates, D. V. The fate of the chronic bronchitic: a report of the ten‐year follow‐up in the Canadian Department of Veterans' Affairs coordinated study of chronic bronchitis. Am. Rev. Respir. Dis. 108: 1043–1065, 1973.
 11. Bates, D. V., P. T. Macklem, and R. V. Christie. Respiratory Function in Disease. Philadelphia, PA: Saunders, 1971, p. 35.
 12. Beale, H. D., W. S. Fowler, and J. H. Comroe, Jr. Pulmonary function studies in 20 asthmatic patients in the symptom‐free interval. J. Allergy 23: 1–12, 1952.
 13. Bedell, G. N., R. Marshall, A. B. DuBois, and J. H. Comroe, Jr. Plethysmographic determination of the volume of gas trapped in the lungs. J. Clin. Invest. 35: 664–670, 1956.
 14. Bedell, G. N., R. Marshall, A. B. DuBois, and J. H. Harris. Measurement of the volume of gas in the gastrointestinal tract. Values in normal subjects and ambulatory patients. J. Clin. Invest. 35: 336–345, 1956.
 15. Belman, M. J., and C. Mittman. Ventilatory muscle training improves exercise capacity in chronic obstructive pulmonary disease patients. Am. Rev. Respir. Dis. 121: 273–280, 1980.
 16. Benater, S. R., T. J. H. Clark, and G. M. Cochrane. Clinical relevance of the flow response to low density gas breathing in asthmatics. Am. Rev. Respir. Dis. 111: 126–134, 1975.
 17. Berend, N., C. Skoog, and W. M. Thurlbeck. Pressure‐volume characteristics of excised human lungs: effects of sex, age, and emphysema. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 558–565, 1980.
 18. Berend, N., C. Skoog, and W. M. Thurlbeck. Exponential analysis of lobar pressure‐flow characteristics. Thorax 36: 452–455, 1981.
 19. Berend, N., and W. M. Thurlbeck. Correlations of maximum expiratory flow with small airway dimensions and pathology. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 346–351, 1982.
 20. Berend, N., A. J. Woolcock, and G. E. Marlin. Correlation between the function and the structure of the lung in smokers. Am. Rev. Respir. Dis. 119: 695–705, 1979.
 21. Berend, N., A. J. Woolcock, and G. E. Marlin. Effects of lobectomy on lung function. Thorax 35: 145–150, 1980.
 22. Black, L. F., R. E. Hyatt, and S. E. Stubbs. Mechanism of expiratory airflow limitation in chronic obstructive pulmonary disease associated with alpha 1‐antitrypsin deficiency. Am. Rev. Respir. Dis. 105: 891–899, 1972.
 23. Black, L. F., K. Offord, and R. E. Hyatt. Variability in the maximal expiratory flow volume curve in asymptomatic smokers and in non‐smokers. Am. Rev. Respir. Dis. 110: 282–292, 1974.
 24. Bode, F. R., J. Dosman, R. R. Martin, and P. T. Macklem. Reversibility of pulmonary function abnormalities in smokers. A prospective study of early diagnostic tests of small airways disease. Am. J. Med. 59: 43–52, 1975.
 25. Bohadana, A. B., R. Peslin, B. Hannhart, and D. Teculescu. Influence of panting frequency on plethysmographic measurements of thoracic gas volume. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 739–747, 1982.
 26. Bosse, R., D. Sparrow, C. L. Rose, and S. T. Weiss. Longitudinal effect of age and smoking cessation on pulmonary function. Am. Rev. Respir. Dis. 123: 378–381, 1981.
 27. Boushy, S. F., M. H. Aboumrad, L. B. North, and A. H. Helgason. Lung recoil pressure, airway resistance and forced flows related to morphological emphysema. Am. Rev. Respir. Dis. 104: 551–561, 1971.
 28. Brown, R., F. G. Hoppin, Jr., R. H. Ingram, Jr., N. A. Saunders, and E. R. McFadden, Jr. Influence of abdominal gas on the Boyle's law determination of thoracic gas volume. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 469–473, 1978.
 29. Brown, R., R. H. Ingram, Jr., and E. R. McFadden, Jr. Problems in the plethysmographic assessment of changes in total lung capacity in asthma. Am. Rev. Respir. Dis. 118: 685–692, 1978.
 30. Brown, R., S. Scharf, and R. H. Ingram, Jr. Nonhomogeneous alveolar pressure swings in the presence of airway closure. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 398–402, 1980.
 31. Brown, R., S. M. Scharf, and R. Ingram, Jr. Nonhomogeneous alveolar pressure swings: effect of different respiratory muscles. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 638–641, 1982.
 32. Brown, R., A. J. Woolcock, N. J. Vincent, and P. T. Macklem. Physiological effects of experimental airway obstruction with beads. J. Appl. Physiol. 27: 328–335, 1969.
 33. Buhain, W. J., J. S. Brody, and A. B. Fisher. Effect of artificial airway obstruction on elastic properties of the lung. J. Appl. Physiol. 33: 589–594, 1972.
 34. Buist, A. S., J. M. Nagy, and G. J. Sexton. Effect of smoking cessation on pulmonary function: a 30‐month follow‐up to two smoking cessation clinics. Am. Rev. Respir. Dis. 120: 953–957, 1979.
 35. Buist, A. S., and B. B. Ross. Predicted values for closing volumes using a modified single breath nitrogen test. Am. Rev. Respir. Dis. 107: 744–752, 1973.
 36. Buist, A. S., and B. B. Ross. Quantitative analysis of the alveolar plateau in the diagnosis of early airway obstruction. Am. Rev. Respir. Dis. 108: 1078–1087, 1973.
 37. Buist, A. S., D. L. Van Fleet, and B. B. Ross. A comparison of conventional spirometric tests and the test of closing volume in an emphysema screening center. Am. Rev. Respir. Dis. 107: 735–743, 1973.
 38. Burger, E. J., Jr., and P. Macklem. Airway closure: demonstration by breathing 100% O2 at low lung volumes and by N2 washout. J. Appl. Physiol. 25: 139–148, 1968.
 39. Burrows, B., and R. H. Earle. Course and prognosis of chronic obstructive lung disease. N. Engl. J. Med. 280: 397–404, 1969.
 40. Burrows, B., F. B. Saksena, and C. F. Diener. Carbon dioxide tension and ventilatory mechanics in chronic obstructive lung disease. Ann. Intern. Med. 65: 685–700, 1966.
 41. Butler, C. Diaphragmatic changes in emphysema. Am. Rev. Respir. Dis. 114: 155–159, 1976.
 42. Butler, J., C. G. Caro, R. Alcala, and A. B. DuBois. Physiological factors affecting airway resistance in normal subjects and in patients with obstructive respiratory disease. J. Clin. Invest. 39: 584–591, 1960.
 43. Byrd, R. B., and R. E. hyatt. Maximal respiratory pressures in chronic obstructive lung disease. Am. Rev. Respir. Dis. 98: 848–856, 1968.
 44. Campbell, A. H., H. Imberger, and B. McC. Jones. Increased upper airway resistance in patients with airway narrowing. Br. J. Dis. Chest 70: 58–65, 1976.
 45. Campbell, E. J. M. Physical signs of diffuse airways obstruction and lung distension. Thorax 24: 1–3, 1969.
 46. Chan‐Yeung, M., R. Abboud, T. M. Sound, and L. MacLean. Effect of helium on maximal expiratory flow in patients with asthma before and during induced bronchoconstriction. Am. Rev. Respir. Dis. 113: 433–443, 1976.
 47. Charan, N. B., J. Hildebrandt, and J. Butler. Alveolar gas compression in smokers and asthmatics. Am. Rev. Respir. Dis. 121: 291–295, 1980.
 48. Cherniack, R. M. The physical properties of the lung in chronic obstructive emphysema. J. Clin. Invest. 35: 394–404, 1956.
 49. Cherniack, R. M. The oxygen consumption and efficiency of the respiratory muscles in health and in emphysema. J. Clin. Invest. 38: 494–499, 1959.
 50. Cherniack, R. M., and A. Hodson. Compliance of the chest wall in chronic bronchitis and emphysema. J. Appl. Physiol. 18: 707–711, 1963.
 51. Cherniack, R. M., and D. S. McCarthy. Reversibility of abnormalities of pulmonary function. In: Lung Biology and Health Disease. The Lung in the Transition Between Health and Disease, edited by P. T. Macklem and S. Permutt. New York: Dekker, 1979, vol. 12, chapt. 15, p. 329–342.
 52. Christie, R. V. The elastic properties of the emphysematous lung and their significance. J. Clin. Invest. 13: 295–321, 1934.
 53. Clark, T. J. H., S. Freedman, E. J. M. Campbell, and R. R. Winn. The ventilatory capacity of patients with chronic airway obstruction. Clin. Sci. 36: 307–316, 1969.
 54. Colebatch, H. J. H., K. E. Finucane, and M. M. Smith. Pulmonary conductance and elastic recoil relationships in asthma and emphysema. J. Appl. Physiol. 34: 143–153, 1973.
 55. Colebatch, H. J. H., I. A. Greaves, and C. K. Y. Ng. Exponential analysis of elastic recoil and aging in healthy males and females. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 47: 683–691, 1979.
 56. Colebatch, H. J. H., I. A. Greaves, and C. K. Y. Ng. Pulmonary mechanics in diagnosis. In: Mechanisms of Airways Obstruction in Human Respiratory Disease, edited by M. A. deKock, J. A. Nadel, and C. M. Lewis. Cape Town: Balkema, 1979, p. 25–47.
 57. Colebatch, H. J. H., C. K. Y. Ng, and N. Nikov. Use of an exponential function for elastic recoil. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 46: 387–393, 1979.
 58. Collett, P. W., T. Brancatisano, and L. A. Engel. Changes in the glottic aperture during bronchial asthma. Am. Rev. Respir. Dis. 128: 719–723, 1983.
 59. Cook, C. D., J. Mead, G. L. Schreiner, N. R. Frank, and J. M. Craig. Pulmonary mechanics during induced pulmonary edema in anesthetized dogs. J. Appl. Physiol. 14: 177–186, 1959.
 60. Corbin, R. P., M. Loveland, R. R. Martin, and P. T. Macklem. A four‐year study of lung mechanics in smokers. Am. Rev. Respir. Dis. 120: 293–304, 1979.
 61. Cormier, Y. F., P. Camus, and M. J. Desmeules. Nonorganic acute upper airway obstruction. Am. Rev. Respir. Dis. 121: 147–150, 1980.
 62. Cosio, M., H. Ghezzo, J. C. Hogg, R. Corbin, M. Loveland, J. Dosman, and P. T. Macklem. The relations between structural changes in small airways and pulmonary function tests. N. Engl. J. Med. 298: 1277–1281, 1978.
 63. Davis, C., E. J. M. Campbell, P. Openshaw, N. B. Pride, and G. Woodroof. Importance of airway closure in limiting maximal expiration in normal man. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 48: 695–701, 1980.
 64. Davis, J., D. H. Glaister, and R. C. Schroter. Assessment of closure of lung units based on the pressure‐volume curve (Abstract). J. Physiol. London 252: 30P, 1975.
 65. Dayman, H. Mechanics of airflow in health and emphysema. J. Clin. Invest. 30: 1175–1190, 1951.
 66. Deal, E. C., Jr., E. R. McFadden, Jr., R. H. Ingram, Jr., and J. J. Jaeger. Effects of atropine on potentiation of exercise‐induced bronchospasm by cold air. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 45: 238–243, 1978.
 67. Demedts, M., J. Clément, D. Stânescu, and K. P. Van de Woestijne. Inflection point on transpulmonary pressure‐volume curves and closing volume. J. Appl. Physiol. 38: 228–235, 1975.
 68. Derenne, J. P., P. T. Macklem, and C. Roussos. The respiratory muscles: mechanics, control and pathophysiology. Am. Rev. Respir. Dis. 118: 581–601, 1978.
 69. Despas, P. J., M. Leroux, and P. T. Macklem. Site of airway obstruction in asthma as determined by measuring maximal expiratory flow breathing air and a helium‐oxygen mixture. J. Clin. Invest. 51: 3235–3243, 1972.
 70. De Troyer, A., and J. Bastenier‐Geens. Effects of neuromuscular blockade on respiratory mechanics in conscious man. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 47: 1162–1168, 1979.
 71. De Troyer, A., and S. Borenstein. Acute changes in respiratory mechanics after pyridostigmine injection in patients with myasthenia gravis. Am. Rev. Respir. Dis. 121: 629–638, 1980.
 72. De Troyer, A., S. Borenstein, and R. Cordier. Analysis of lung volume restriction in patients with respiratory muscle weakness. Thorax 35: 603–610, 1980.
 73. De Troyer, A., and P. Deisser. The effects of intermittent positive pressure breathing on patients with respiratory muscle weakness. Am. Rev. Respir. Dis. 124: 132–137, 1981.
 74. De Troyer, A., M. Estenne, and J. C. Yernault. Disturbance of respiratory muscle function in patients with mitral valve disease. Am. J. Med. 69: 867–873, 1980.
 75. De Troyer, A., and A. Heilporn. Respiratory mechanics in quadriplegia. The respiratory function of the intercostal muscles. Am. Rev. Respir. Dis. 122: 591–600, 1980.
 76. Dirksen, H., L. Janzon, and S. E. Lindell. Influence of smoking and cessation of smoking on lung function. Scand. J. Respir. Dis. Suppl. 85: 226–270, 1974.
 77. Dollfuss, R. E., J. Milic‐Emili, and D. V. Bates. Regional ventilation of the lung, studied with boluses of 133xenon. Respir. Physiol. 2: 234–246, 1967.
 78. Dolovich, M. B., J. Sanchis, C. Rossman, and M. T. Newhouse. Aerosol penetrance: a sensitive index of peripheral airways obstruction. J. Appl. Physiol. 40: 468–471, 1976.
 79. Dosman, J., F. Bode, J. Urbanetti, R. Martin, and P. T. Macklem. The use of a helium‐oxygen mixture during maximum expiratory flow to demonstrate obstruction in small airways in smokers. J. Clin. Invest. 55: 1090–1099, 1975.
 80. DuBois, A. B., S. Y. Botelho, G. N. Bedell, R. Marshall, and J. H. Comroe, Jr. A rapid plethysmographic method for measuring thoracic gas volume: a comparison with a nitrogen washout method for measuring functional residual capacity in normal subjects. J. Clin. Invest. 35: 322–326, 1956.
 81. DuBois, A. B., S. Y. Botelho, and J. H. Comroe, Jr. A new method for measuring airway resistance in man using a body plethysmograph: values in normal subjects and in patients with respiratory disease. J. Clin. Invest. 35: 327–335, 1956.
 82. Duffell, G. M., J. H. Marcus, and R. H. Ingram, Jr. Limitation of expiratory flow in chronic obstructive pulmonary disease. Relation of clinical characteristics, pathophysiological type, and mechanisms. Ann. Intern. Med. 72: 365–374, 1970.
 83. Dunnill, M. S. The pathology of asthma. In: Identification of Asthma, edited by R. Porter and J. Birch. London: Churchill Livingstone, 1971, p. 35–40. (Ciba Found. Study Group, no. 38.)
 84. Dunnill, M. S. Pulmonary Pathology. Edinburgh: Churchill Livingstone, 1982, p. 50–62.
 85. Dutu, S., and Z. Jienescu. Evaluation clinique des différents indices d'élasticité pulmonaire. Bull. Physio‐Pathol. Respir. 7: 603–614, 1971.
 86. Engel, L. A., A. Grassino, and N. R. Anthonisen. Demonstration of airway closure in man. J. Appl. Physiol. 38: 1117–1125, 1975.
 87. Enjeti, S., N. Hazelwood, and S. Permutt. Pulmonary function in young smokers: male‐female differences. Am. Rev. Respir. Dis. 118: 667–676, 1978.
 88. Fairshter, R. D., and A. F. Wilson. Relationship between the site of airflow limitation and localization of the bronchodilator response in asthma. Am. Rev. Respir. Dis. 122: 27–32, 1980.
 89. Fairshter, R. D., and A. F. Wilson. Relationship between sites of airflow limitation and severity of chronic airflow obstruction. Am. Rev. Respir. Dis. 123: 3–7, 1981.
 90. Farkas, G. A., and C. roussos. Adaptability of the hamster diaphragm to exercise and/or emphysema. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 1263–1272, 1982.
 91. Fazio, F., A. Palla, A. Santolicandro, S. Solfanelli, E. Fornai, and C. Giuntini. Studies of regional ventilation in asthma using 81mKr. Lung 156: 185–194, 1979.
 92. Finucane, K. E., and H. J. H. Colebatch. Elastic behavior of the lung in patients with airway obstruction. J. Appl. Physiol. 26: 330–338, 1969.
 93. Fisher, A. B., A. B. DuBois, and R. W. Hyde. Evaluation of the forced oscillation technique for the determination of resistance to breathing. J. Clin. Invest. 47: 2045–2057, 1968.
 94. Fitzgerald, M. X., P. J. Keelan, D. W. Cugell, and E. A. gaensler. Long‐term results of surgery for bullous emphysema. J. Thorac. Cardiovasc. Surg. 68: 566–586, 1974.
 95. Flenley, D. C., L. Welchel, and P. T. Macklem. Factors affecting gas exchange by collateral ventilation in the dog. Respir. Physiol. 15: 52–69, 1972.
 96. Fletcher, C. M., and R. Peto. The natural history of chronic airflow obstruction. Br. Med. J. 1: 1645–1648, 1977.
 97. Forkert, L., S. Dhingra, and N. R. Anthonisen. Airway closure and closing volume. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 46: 24–30, 1979.
 98. Freedman, S. Sustained maximum voluntary ventilation. Respir. Physiol. 8: 230–244, 1970.
 99. Freedman, S., A. E. Tattersfield, and N. B. Pride. Changes in lung mechanics during asthma induced by exercise. J. Appl. Physiol. 38: 974–982, 1975.
 100. Fry, D. L., R. V. Ebert, W. W. Stead, and C. C. Brown. The mechanics of pulmonary ventilation in normal subjects and in patients with emphysema. Am. J. Med. 16: 80–97, 1954.
 101. Fry, D. L., and R. E. Hyatt. Pulmonary mechanics: a unified analysis of the relationship between pressure, volume, and gas flow in the lungs of normal and diseased subjects. Am. J. Med. 29: 672–689, 1960.
 102. Fullton, J. M., D. A. Hayes, and R. L. Pimmel. Pulmonary impedance in dogs measured by forced random noise with a retrograde catheter. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 725–733, 1982.
 103. Fulmer, J. D., W. C. Roberts, E. R. von Gal, and R. G. Crystal. Small airways in idiopathic pulmonary fibrosis. Comparison of morphologic and physiologic observations. J. Clin. Invest. 60: 595–610, 1977.
 104. Gaensler, E. A. Lung displacement: abdominal enlargement, pleural space disorders, deformities of the thoracic cage. In: Handbook of Physiology. Respiration, edited by W. O. Fenn and H. Rahn. Washington, DC: Am. Physiol. Soc, 1965, sect. 3, vol. II, chapt. 73, p. 1623–1661.
 105. Gal, T. J., and S. K. Goldberg. Relationship between respiratory muscle strength and vital capacity during partial curarization in awake subjects. Anesthesiology 54: 141–147, 1981.
 106. Gamsu, G., D. B. Borson, W. R. Webb, and J. H. Cunningham. Structure and function in tracheal stenosis. Am. Rev. Respir. Dis. 121: 519–531, 1980.
 107. Gastaut, H. C., C. A. Tassinari, and B. Duron. Polygraphic study of the episodic diurnal and nocturnal (hypnic and respiratory) manifestations of the Pickwickian syndrome. Brain Res. 2: 167–186, 1966.
 108. Gelb, A. F., W. M. Gold, and J. A. Nadel. Mechanisms limiting airflow in bullous lung disease. Am. Rev. Respir. Dis. 107: 571–578, 1973.
 109. Gelb, A. F., W. M. Gold, R. R. Wright, H. R. Bruck, and J. A. Nadel. Physiologic diagnosis of subclinical emphysema. Am. Rev. Respir. Dis. 107: 50–63, 1973.
 110. Gibson, G. J., E. Clark, and N. B. Pride. Static transdiaphragmatic pressures in normal subjects and in patients with chronic hyperinflation. Am. Rev. Respir. Dis. 124: 685–689, 1981.
 111. Gibson, G. J., and N. B. Pride. Pulmonary mechanics in fibrosing alveolitis. The effects of lung shrinkage. Am. Rev. Respir. Dis. 116: 637–647, 1977.
 112. Gibson, G. J., and N. B. Pride. Lung mechanics in diaphragmatic paralysis. Am. Rev. Respir. Dis. 119: 119–120, 1979.
 113. Gibson, G. J., N. B. Pride, J. Davis, and R. C. Schroter. Exponential description of the static pressure‐volume curve of normal and diseased lung. Am. Rev. Respir. Dis. 120: 799–811, 1979.
 114. Gibson, G. J., N. B. Pride, and D. W. Empey. The role of inspiratory dynamic compression in upper airway obstruction. Am. Rev. Respir. Dis. 108: 1352–1360, 1973.
 115. Gibson, G. J., N. B. Pride, J. Newsom Davis, and L. C. Loh. Pulmonary mechanics in patients with respiratory muscle weakness. Am. Rev. Respir. Dis. 115: 389–395, 1977.
 116. Glaister, D. H., R. C. Schroter, M. F. Sudlow, and J. Milic‐Emili. Bulk elastic properties of excised lungs and the effect of a transpulmonary pressure gradient. Respir. Physiol. 17: 347–364, 1973.
 117. Gold, W. M., H. S. Kaufman, and J. A. Nadel. Elastic recoil of the lungs in chronic asthmatic patients before and after therapy. J. Appl. Physiol. 23: 433–438, 1967.
 118. Greaves, I. A., and H. J. H. Colebatch. Elastic behavior and structure of normal and emphysematous lungs post‐mortem. Am. Rev. Respir. Dis. 121: 127–136, 1980.
 119. Grimby, G., B. Elgefors, and H. Oxhoj. Ventilatory levels and chest wall mechanics during exercise in obstructive lung disease. Scand. J. Respir. Dis. 54: 45–52, 1973.
 120. Grimby, G., T. Takishima, W. Graham, P. Macklem, and J. Mead. Frequency dependence of flow resistance in patients with obstructive lung disease. J. Clin. Invest. 47: 1455–1465, 1968.
 121. Habib, M. P., and L. A. Engel. Influence of the panting technique on the plethysmographic measurement of thoracic gas volume. Am. Rev. Respir. Dis. 117: 265–271, 1978.
 122. Hall, W. J., R. J. Douglas, R. W. Hyde, F. K. Roth, A. S. Cross, and D. M. Speers. Pulmonary mechanics after uncomplicated influenza A infection. Am. Rev. Respir. Dis. 113: 141–147, 1976.
 123. Hall, W. J., R. W. Hyde, R. H. Schwartz, G. S. Mudholkar, D. R. Webb, Y. P. Chaubey, and P. L. Townes. Pulmonary abnormalities in intermediate alpha1‐antitrypsin deficiency. J. Clin. Invest. 58: 1069–1077, 1976.
 124. Haponik, E. F., E. R. Bleecker, R. P. Allen, P. L. Smith, and J. Kaplan. Abnormal inspiratory flow‐volume curves in patients with sleep‐disordered breathing. Am. Rev. Respir. Dis. 124: 571–574, 1981.
 125. Hayes, D. A., R. L. Pimmel, J. M. Fullton, and P. A. Bromberg. Detection of respiratory mechanical dysfunction by forced random noise impedance parameters. Am. Rev. Respir. Dis. 120: 1095–1100, 1979.
 126. Heckscher, T., H. Bass, A. Oriol, B. Rose, N. R. Anthonisen, and D. V. Bates. Regional lung function in patients with bronchial asthma. J. Clin. Invest. 47: 1063–1070, 1968.
 127. Hedstrand, U. Ventilation, gas exchange, mechanics of breathing and respiratory work in acute bronchial asthma. Acta Soc. Med. Ups. 76: 248–270, 1971.
 128. Hetzel, M. R., and T. J. H. Clark. Comparisons of normal and asthmatic circadian rhythms in peak expiratory flow rate. Thorax 35: 732–738, 1980.
 129. Higenbottam, T. Narrowing of glottis opening in humans associated with experimentally induced bronchoconstriction. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 403–407, 1980.
 130. Higenbottam, T., and J. Payne. Glottis narrowing in lung disease. Am. Rev. Respir. Dis. 125: 745–750, 1982.
 131. Hoeppner, V. H., D. M. Cooper, N. Zamel, A. C. Bryan, and H. Levison. Relationship between elastic recoil and closing volume in smokers and nonsmokers. Am. Rev. Respir. Dis. 109: 81–86, 1974.
 132. Hogg, J. C., P. T. Macklem, and W. M. Thurlbeck. Site and nature of airway obstruction in chronic obstructive lung disease. N. Engl. J. Med. 278: 1355–1360, 1968.
 133. Hogg, J. C., P. T. Macklem, and W. M. Thurlbeck. The resistance of collateral channels in excised human lungs. J. Clin. Invest. 48: 421–431, 1969.
 134. Hogg, J. C., S. J. Nepszy, P. T. Macklem, and W. M. Thurlbeck. Elastic properties of the centrilobular emphysematous space. J. Clin. Invest. 48: 1306–1312, 1969.
 135. Hoppin, F. G., Jr., M. Green, and M. S. Morgan. Relationship of central and peripheral airway resistance to lung volume in dogs. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 728–737, 1978.
 136. Hughes, J. A., D. C. S. Hutchison, D. Bellamy, D. E. Dowd, K. C. Ryan, and P. Hugh‐Jones. The influence of cigarette smoking and its withdrawal on the annual change of lung function in pulmonary emphysema. Q. J. Med. 51: 115–124, 1982.
 137. Hurtado, A., and N. L. Kaltreider. Studies of total pulmonary capacity and its subdivisions. VII. Observations during the acute respiratory distress of bronchial asthma and following the administration of epinephrine. J. Clin. Invest. 13: 1053–1062, 1934.
 138. Hurtado, A., N. L. Kaltreider, W. W. Fray, W. D. W. Brooks, and W. S. McCann. Studies of total pulmonary capacity and its subdivisions. VI. Observations on cases of obstructive pulmonary emphysema. J. Clin. Invest. 13: 1027–1051, 1934.
 139. Hutcheon, M., P. Griffin, H. Levison, and N. Zamel. Volume of isoflow. A new test in detection of mild abnormalities of lung mechanics. Am. Rev. Respir. Dis. 110: 458–465, 1974.
 140. Hyatt, R. E. The interrelationship of pressure, flow and volume during various respiratory maneuvers in normal and emphysematous subjects. Am. Rev. Respir. Dis. 83: 676–683, 1961.
 141. Hyatt, R. E., and R. E. Flath. Influence of lung parenchyma on pressure‐diameter behavior of dog bronchi. J. Appl. Physiol. 21: 1448–1452, 1966.
 142. Inglestedt, S., and B. Jonson. On the mechanics of the extrathoracic airways. Acta Oto‐Laryngol. Suppl. 224: 518–520, 1967.
 143. Ingram, R. H., Jr., and E. R. McFadden, Jr. Localization and mechanisms of airway responses. N. Engl. J. Med. 297: 596–600, 1977.
 144. ingram, R. H., Jr., and C. F. O'Cain. Frequency dependence of compliance in apparently healthy smokers versus nonsmokers. Bull. Physio‐Pathol. Respir. 7: 195–212, 1971.
 145. Ingram, R. H., Jr., C. F. O'Cain, and W. W. Fridy, Jr. Simultaneous quasi‐static lung pressure‐volume curves and “closing volume” measurements. J. Appl. Physiol. 36: 135–141, 1974.
 146. Ingram, R. H., Jr., and D. P. Schilder. Effect of gas compression on pulmonary pressure, flow, and volume relationship. J. Appl. Physiol. 21: 1821–1826, 1966.
 147. Ingram, R. H., Jr., and D. P. Schilder. Association of a decrease in dynamic compliance with a change in gas distribution. J. Appl. Physiol. 23: 911–916, 1967.
 148. ishikawa, S., and J. A. hayes. Functional morphometry of the diaphragm in patients with chronic obstructive lung disease. Am. Rev. Respir. Dis. 108: 135–138, 1973.
 149. Jonson, B. Pulmonary mechanics in patients with pulmonary disease, studied with the flow regulator method. Scand. J. Clin. Lab. Invest. 25: 375–390, 1970.
 150. Kaneko, K., and O. P. Sharma. Airway obstruction in pulmonary sarcoidosis. Bull. Eur. Physiopathol. Respir. 13: 231–240, 1977.
 151. Katz, J. A., S. E. Zinn, G. M. Ozanne, and H. B. Fairley. Pulmonary, chest wall, and lung‐thorax elastances in acute respiratory failure. Chest 80: 304–311, 1981.
 152. Kieldgaard, J. M., R. W. hyde, D. M. speers, and W. W. Reichert. Frequency dependence of total respiratory resistance in early airway disease. Am. Rev. Respir. Dis. 114: 501–508, 1976.
 153. Knudson, R. J., B. Burrows, and M. D. Lebowitz. The maximal expiratory flow‐volume curve: its use in the detection of ventilatory abnormalities in a population study. Am. Rev. Respir. Dis. 114: 871–879, 1976.
 154. Knudson, R. J., D. F. Clark, T. C. Kennedy, and D. E. Knudson. Effect of aging alone on mechanical properties of the normal adult human lung. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 43: 1054–1062, 1977.
 155. Knudson, R. J., and W. T. Kaltenhorn. Evaluation of lung elastic recoil by exponential curve analysis. Respir. Physiol. 46: 29–42, 1981.
 156. Knudson, R. J., M. D. Lebowitz, A. P. Burton, and D. E. Knudson. The closing volume test: evaluation of nitrogen and bolus methods in a random population. Am. Rev. Respir. Dis. 115: 423–434, 1977.
 157. Kreitzer, S. M., N. A. Saunders, H. R. Tyler, and R. H. Ingram. Respiratory muscle function in amyotrophic lateral sclerosis. Am. Rev. Respir. Dis. 117: 437–447, 1978.
 158. Landau, L. I., and P. D. Phelan. The spectrum of cystic fibrosis. A study of pulmonary mechanics in 46 patients. Am. Rev. Respir. Dis. 108: 593–602, 1973.
 159. Lándsér, F. J., Clément, J., and K. P. van de Woestijne. Normal values of total respiratory resistance and reactance determined by forced oscillations: influence of smoking. Chest 81: 586–591, 1982.
 160. Lándsér, F. J., J. Nagels, M. Demedts, L. Billiet, and K. P. van de Woestijne. A new method to determine frequency characteristics of the respiratory system. J. Appl. Physiol. 41: 101–106, 1976.
 161. Laurenzi, G. A., G. M. Turino, and A. P. Fishman. Bullous disease of the lung. Am. J. Med. 32: 361–378, 1962.
 162. Lavelle, T. F., Jr., H. H. Rotman, and J. G. Weg. Isoflow‐volume curves in the diagnosis of upper airway obstruction. Am. Rev. Respir. Dis. 117: 845–852, 1978.
 163. Leaver, D. G., and N. B. Pride. Flow‐volume curves and expiratory pressures during exercise in patients with chronic airways obstruction. Scand. J. Respir. Dis. Suppl. 77: 23–27, 1971.
 164. Leaver, D. G., A. E. Tattersfield, and N. B. Pride. Contributions of loss of lung recoil and of enhanced airways collapsibility to the airflow obstruction of chronic bronchitis and emphysema. J. Clin. Invest. 52: 2117–2128, 1973.
 165. Leaver, D. G., A. E. Tattersfield, and N. B. Pride. Bronchial and extrabronchial factors in chronic airflow obstruction. Thorax 29: 394–400, 1974.
 166. Leblanc, P., F. Ruff, and J. Milic‐Emili. Effects of age and body position on “airway closure” in man. J. Appl. Physiol. 28: 448–451, 1970.
 167. Levine, G., E. Housley, P. MacLeod, and P. T. Macklem. Gas exchange in mild bronchitis and asymptomatic asthma. N. Engl. J. Med. 282: 1277–1282, 1970.
 168. Levinson, R. S., L. F. Metzger, N. N. Stanley, S. G. Kelsen, M. D. Altose, N. S. Cherniack, and J. S. Brody. Airway function in sarcoidosis. Am. J. Med. 62: 51–59, 1977.
 169. Levison, H., and R. M. Cherniack. Ventilatory cost of exercise in chronic obstructive pulmonary disease. J. Appl. Physiol. 25: 21–27, 1968.
 170. Libby, D. M., W. A. Briscoe, and T. K. C. King. Relief of hypoxia‐related bronchoconstriction by breathing 30 percent oxygen. Am. Rev. Respir. Dis. 123: 171–175, 1981.
 171. Lisboa, C., J. Jardim, E. Angus, and P. T. Macklem. Is extra‐thoracic airway obstruction important in asthma? Am. Rev. Respir. Dis. 122: 115–121, 1980.
 172. Lisboa, C., P. T. Macklem, and L. D. H. Wood. Density dependence of pulmonary pressure‐flow curves and maximum expiratory flow. In: Small Airways in Health and Disease, edited by P. Sadoul, J. Milic‐Emili, B. G. Simonsson, and T. J. H. Clark. Amsterdam: Excerpta Med., 1979, p. 17–20.
 173. Loyd, H. M., T. I. String, and A. B. DuBois. Radiographic and plethysmographic determination of total lung capacity. Radiology 86: 7–14, 1966.
 174. Macklem, P. T. Airway obstruction and collateral ventilation. Physiol. Rev. 51: 368–436, 1971.
 175. Macklem, P. T. Changes in lung mechanics. Pressure‐volume and pressure‐flow relations. In: Lung Biology in Health and Disease. The Lung in the Transition Between Health and Disease, edited by P. T. Macklem and S. Permutt. New York: Dekker, 1979, vol. 12, chapt. 4, p. 53–71.
 176. Macklem, P. T., and M. R. Becklake. The relationship between mechanical and diffusing properties of the lung in health and disease. Am. Rev. Respir. Dis. 87: 47–56, 1963.
 177. Macklem, P. T., R. G. Fraser, and W. G. Brown. Bronchial pressure measurements in emphysema and bronchitis. J. Clin. Invest. 44: 897–905, 1965.
 178. Macklem, P. T., and S. Permutt (editors). Lung Biology in Health and Disease. The Lung in the Transition Between Health and Disease. New York: Dekker, 1979, vol. 12.
 179. Macklem, P. T., D. F. Proctor, and J. C. Hogg. The stability of peripheral airways. Respir. Physiol. 8: 191–203, 1970.
 180. Macklem, P. T., and N. J. Wilson. Measurement of intrabronchial pressure in man. J. Appl. Physiol. 20: 653–663, 1965.
 181. Mansell, A., C. Bryan, and H. Levison. Airway closure in children. J. Appl. Physiol. 33: 711–714, 1972.
 182. Mansell, A., C. Dubrawsky, H. Levison, A. C. Bryan, H. Langer, C. Collins‐Williams, and R. P. Orange. Lung mechanics in antigen‐induced asthma. J. Appl. Physiol. 37: 297–301, 1974.
 183. Marcq, M., and A. Minette. Lung function changes in smokers with normal conventional spirometry. Am. Rev. Respir. Dis. 114: 723–738, 1976.
 184. Marrazzini, L., R. Cavestri, D. Gori, L. Gatti, and E. Longhini. Difference between mouth and esophageal occlusion pressure during CO2 rebreathing in chronic obstructive pulmonary disease. Am. Rev. Respir. Dis. 118: 1027–1033, 1978.
 185. Marshall, R., R. W. Stone, and R. V. Christie. The relationship of dyspnoea to respiratory effort in normal subjects, mitral stenosis and emphysema. Clin. Sci. 13: 625–631, 1954.
 186. Martin, J., E. Powell, S. Shore, J. Emrich, and L. A. Engel. The role of respiratory muscles in the hyperinflation of bronchial asthma. Am. Rev. Respir. Dis. 121: 441–447, 1980.
 187. Martin, R. R., D. Lindsay, P. Despas, D. Bruce, M. Leroux, N. R. Anthonisen, and P. T. Macklem. The early detection of airway obstruction. Am. Rev. Respir. Dis. 111: 119–125, 1975.
 188. Matsuba, K., and W. M. Thurlbeck. Disease of the small airways in chronic bronchitis. Am. Rev. Respir. Dis. 107: 552–558, 1973.
 189. McBride, J. T., M. E. B. Wohl, D. J. Strieder, A. C. Jackson, J. R. Morton, R. G. Zwerdling, N. T. Griscom, S. Treves, A. J. Williams, and S. Schuster. Lung growth and airway function after lobectomy in infancy for congenital lobar emphysema. J. Clin. Invest. 66: 962–970, 1980.
 190. McCarthy, D. S., D. B. Craig, and R. M. Cherniack. Effect of modification of the smoking habit on lung function. Am. Rev. Respir. Dis. 114: 103–113, 1976.
 191. McCarthy, D., and J. Milic‐Emili. Closing volume in asymptomatic asthma. Am. Rev. Respir. Dis. 107: 559–570, 1973.
 192. McCarthy, D. S., R. Spencer, R. Greene, and J. Milic‐Emili. Measurement of “closing volume” as a simple and sensitive test for early detection of small airway disease. Am. J. Med. 52: 747–753, 1972.
 193. McFadden, E. R., Jr., R. H. Ingram, Jr., R. L. Haynes, and J. J. Wellman. Predominant site of flow limitation and mechanisms of postexertional asthma. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 42: 746–752, 1977.
 194. McFadden, E. R., Jr., and H. A. Lyons. Airway resistance and uneven ventilation in bronchial asthma. J. Appl. Physiol. 25: 365–370, 1968.
 195. McFadden, E. R., Jr., and H. A. Lyons. Serial studies of factors influencing airway dynamics during recovery from acute asthma attacks. J. Appl. Physiol. 27: 452–459, 1969.
 196. McIlroy, M. B., and D. V. Bates. Respiratory function after pneumonectomy. Thorax 11: 303–311, 1956.
 197. Mead, J. Contribution of compliance of airways to frequency‐dependent behavior of lungs. J. Appl. Physiol. 26: 670–673, 1969.
 198. Mead, J., I. Lindgren, and E. A. Gaensler. The mechanical properties of the lungs in emphysema. J. Clin. Invest. 34: 1005–1016, 1955.
 199. Mead, J., T. Takishima, and D. Leith. Stress distribution in lungs: a model of pulmonary elasticity. J. Appl. Physiol. 28: 596–608, 1970.
 200. Mead, J., J. M. Turner, P. T. Macklem, and J. B. Little. Significance of the relationship between lung recoil and maximum expiratory flow. J. Appl. Physiol. 22: 95–108, 1967.
 201. Meadows, J. A., III, J. R. Rodarte, and R. E. Hyatt. Density dependence of maximal expiratory flow in chronic obstructive pulmonary disease. Am. Rev. Respir. Dis. 121: 47–54, 1980.
 202. Michaelson, E. D., E. D. Grassman, and W. R. Peters. Pulmonary mechanics by spectral analysis of forced random noise. J. Clin. Invest. 56: 1210–1230, 1975.
 203. Miller, R. D., and R. E. Hyatt. Obstructing lesions of the larynx and trachea: clinical and physiologic characteristics. Mayo Clin. Proc. 44: 145–161, 1969.
 204. Miller, R. D., and R. E. Hyatt. Evaluation of obstructing lesions of the trachea and larynx by flow‐volume loops. Am. Rev. Respir. Dis. 108: 475–481, 1973.
 205. Mink, S. N., and L. D. H. Wood. How does HeO2 increase maximum expiratory flow in human lungs? J. Clin. Invest. 66: 720–729, 1980.
 206. Morris, J. F., A. Koski, and J. D. Breese. Normal values and evaluation of forced end‐expiratory flow. Am. Rev. Respir. Dis. 111: 755–762, 1975.
 207. Muller, N., A. C. Bryan, and N. Zamel. Tonic inspiratory muscle activity as a cause of hyperinflation in histamine‐induced asthma. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 869–874, 1980.
 208. Muller, N., A. C. Bryan, and N. Zamel. Tonic inspiratory muscle activity as a cause of hyperinflation in asthma. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 50: 279–282, 1981.
 209. Murphy, D. M. F., D. R. Hall, M. R. Petersen, and N. L. Lapp. The effect of diffuse pulmonary fibrosis on lung mechanics. Bull. Eur. Physiopathol. Respir. 17: 27–41, 1981.
 210. Nagels, J., F. J. Lándsér, L. Van der Linden, J. Clément, and K. P. Van de Woestijne. Mechanical properties of lungs and chest wall during spontaneous breathing. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 408–416, 1980.
 211. Newsom Davis, J., M. Goldman, L. Loh, and M. Casson. Diaphragm function and alveolar hypoventilation. Q. J. Med. 45: 87–100, 1976.
 212. Nicklaus, T. M., S. Watanabe, M. M. Mitchell, and A. D. Renzetti, Jr. Roentgenologic, physiologic and structural estimations of the total lung capacity in normal and emphysematous subjects. Am. J. Med. 12: 547–553, 1967.
 213. Niewoehner, D. E., and J. Kleinerman. Morphologic basis of pulmonary resistance in the human lung and effects of aging. J. Appl. Physiol. 36: 412–418, 1974.
 214. Niewoehner, D. E., J. Kleinerman, and D. B. Rice. Pathologic changes in the peripheral airways of young cigarette smokers. N. Engl. J. Med. 291: 755–758, 1974.
 215. Niewoehner, D. E., J. D. Knoke, and J. Kleinerman. Peripheral airways as a determinant of ventilatory function in the human lung. J. Clin. Invest. 60: 139–151, 1977.
 216. O'Connell, J. M., and A. H. Campbell. Respiratory mechanics in airways obstruction associated with inspiratory dyspnoea. Thorax 31: 669–677, 1976.
 217. Olive, J. T., Jr., and R. E. Hyatt. Maximal expiratory flow and total respiratory resistance during induced bronchoconstriction in asthmatic subjects. Am. Rev. Respir. Dis. 106: 366–383, 1972.
 218. Ostrow, D., and R. M. Cherniack. Resistance to airflow in patients with diffuse interstitial lung disease. Am. Rev. Respir. Dis. 108: 205–210, 1973.
 219. Oxhøj, H., B. Bake, and L. Wilhelmsen. Spirometry and flow‐volume curves in 10‐year follow‐up of men born in 1913. Scand. J. Respir. Dis. 57: 310–312, 1976.
 220. Pardy, R. L., R. N. Rivington, P. J. Despas, and P. T. Macklem. Inspiratory muscle training compared with physiotherapy in patients with chronic airflow limitation. Am. Rev. Respir. Dis. 123: 421–425, 1981.
 221. Pardy, R. L., R. N. Rivington, P. J. Despas, and P. T. Macklem. The effects of inspiratory muscle training on exercise performance in chronic airflow limitation. Am. Rev. Respir. Dis. 123: 426–433, 1981.
 222. Paré, P. D., L. A. Brooks, J. Bates, L. M. Lawson, J. M. B. Nelems, J. L. Wright, and J. C. Hogg. Exponential analysis of the lung pressure‐volume curve as a predictor of pulmonary emphysema. Am. Rev. Respir. Dis. 126: 54–61, 1982.
 223. Paré, P. D., B. J. R. Wiggs, and C. A. Coppin. Errors in the measurement of total lung capacity in chronic obstructive lung disease. Thorax 38: 468–471, 1983.
 224. Park, S. S., M. Janis, C. S. Shim, and M. H. Williams, Jr. Relationship of bronchitis and emphysema to altered pulmonary function. Am. Rev. Respir. Dis. 102: 927–936, 1970.
 225. Park, S. S., O. H. Yoo, M. Janis, and M. H. Williams, Jr. Postmortem evaluation of airflow limitation in obstructive lung disease. J. Appl. Physiol. 27: 308–312, 1969.
 226. Partridge, M. R., and K. B. Saunders. The site of airflow limitation in asthma: the effect of time, acute exacerbations of disease and clinical features. Br. J. Dis. Chest 75: 263–272, 1981.
 227. Pedersen, O. F., R. G. Castile, J. M. Drazen, and R. H. Ingram, Jr. Density dependence of maximum expiratory flow in the dog. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 53: 397–404, 1982.
 228. Peress, L., G. Sybrecht, and P. T. Macklem. The mechanisms of increase in total lung capacity during acute asthma. Am. J. Med. 61: 165–169, 1976.
 229. Permutt, S. Some physiological aspects of asthma: bronchomuscular contraction and airway calibre. In: Identification of Asthma, edited by R. Porter and J. Birch. London: Churchill Livingstone, 1971, p. 63–75. (Ciba Found. Study Group, no. 38.)
 230. Permutt, S. Physiologic changes in the acute asthmatic attack. In: Asthma: Physiology, Immunopharmacology, and Treatment, edited by K. F. Austen and L. M. Lichtenstein. New York: Academic, 1973, p. 15–24.
 231. Peslin, R., B. Hannhart, and J. Pino. Impédance mécanique thoraco‐pulmonaire chez des sujets fumeurs et nonfumeurs. Bull. Eur. Physiopathol. Respir. 17: 93–105, 1981.
 232. Petrik‐Pereira, R., D. Hunter, and N. B. Pride. Use of lung pressure‐volume curves and helium‐sulphur hexafluoride washout to detect emphysema in patients with mild airflow obstruction. Thorax 36: 29–37, 1981.
 233. Pierce, J. A., and J. H. Growdon. Physical properties of the lungs in giant cysts. N. Engl. J. Med. 267: 169–173, 1962.
 234. Potter, W. A., S. Olafsson, and R. E. Hyatt. Ventilatory mechanics and expiratory flow limitation during exercise in patients with obstructive lung disease. J. Clin. Invest. 50: 910–919, 1971.
 235. Pride, N. B., C. E. Barter, and P. Hugh‐Jones. The ventilation of bullae and the effect of their removal on thoracic gas volumes and tests of overall pulmonary function. Am. Rev. Respir. Dis. 107: 83–98, 1973.
 236. Pride, N. B., S. Permutt, R. L. Riley, and B. Bromberger‐Barnea. Determinants of maximal expiratory flow from the lungs. J. Appl. Physiol. 23: 646–662, 1967.
 237. Rahn, H., A. B. Otis, L. E. Chadwick, and W. O. Fenn. The pressure‐volume diagram of the thorax and lung. Am. J. Physiol. 146: 161–178, 1946.
 238. Raimondi, A. C., R. H. T. Edwards, D. M. Denison, D. G. Leaver, R. G. Spencer, and J. A. Siddorn. Exercise tolerance breathing a low density gas mixture, 35% oxygen and air in patients with chronic obstructive bronchitis. Clin. Sci. 39: 675–685, 1970.
 239. Remmers, J. E., W. J. deGroot, E. K. Sauerland, and A. M. Anch. Pathogenesis of upper airway occlusion during sleep. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 931–938, 1978.
 240. Rodenstein, D. O., and D. C. Stânescu. Reassessment of lung volume measurement by helium dilution and by body plethysmography in chronic airflow obstruction. Am. Rev. Respir. Dis. 126: 1040–1044, 1982.
 241. Rodenstein, D., and D. C. Stânescu. Elastic properties of the lung in acute induced asthma. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 54: 152–158, 1983.
 242. Rodenstein, D. O., D. C. Stânescu, and C. Francis. Demonstration of failure of body plethysmography in airway obstruction. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 949–954, 1982.
 243. Rogers, R. M., A. B. DuBois, and W. S. Blakemore. Effect of removal of bullae on airway conductance and conductance‐volume ratios. J. Clin. Invest. 47: 2569–2579, 1968.
 244. Rohrer, R. Der Zusammenhang der Atemkräfte und ihre Abhängigkeit vom Dehnungszustand der Atmungsorgane. Pfluegers Arch. Gesamte Physiol. Menschen Tiere 165: 419–444, 1916.
 245. Sackner, M. A. Physiologic features of upper airway obstruction. Chest 62: 414–417, 1972.
 246. Saksena, E. B., and B. Burrows. Thoracic compliance in chronic obstructive lung disease. J. Lab. Clin. Med. 68: 427–432, 1966.
 247. Salazar, E., and J. H. Knowles. An analysis of pressure‐volume characteristics of the lungs. J. Appl. Physiol. 19: 97–104, 1964.
 248. Schlueter, D. P., J. Immekus, and W. W. Stead. Relationship between maximal inspiratory pressure and total lung capacity (coefficient of retraction) in normal subjects and in patients with emphysema, asthma, and diffuse pulmonary infiltration. Am. Rev. Respir. Dis. 96: 656–665, 1967.
 249. Scott, K. W. M., and J. Hoy. The cross‐sectional area of diaphragmatic muscle fibers in emphysema, measured by an automated image analysis system. J. Pathol. 110: 121–128, 1976.
 250. Serisier, D. E., F. L. Mastaglia, and G. J. Gibson. Respiratory muscle function and ventilatory control. I. In patients with motor neurone disease. II. In patients with myotonic dystrophy. Q. J. Med. 51: 205–226, 1982.
 251. Sharp, J. T., N. B. Goldberg, W. S. Druz, H. C. Fishman, and J. Danon. Thoracoabdominal motion in chronic obstructive pulmonary disease. Am. Rev. Respir. Dis. 115: 47–56, 1977.
 252. Sharp, J. T., G. T. Griffith, I. L. Bunnell, and D. G. Greene. Ventilatory mechanics in pulmonary edema in man. J. Clin. Invest. 37: 111–117, 1958.
 253. Sharp, J. T., P. van Lith, C. Vej Nuchprayoon, R. Briney, and F. N. Johnson. The thorax in chronic obstructive lung disease. Am. J. Med. 44: 39–46, 1968.
 254. Shim, C., P. Corro, S. S. Park, and M. H. Williams. Pulmonary function studies in patients with upper airway obstruction. Am. Rev. Respir. Dis. 106: 233–238, 1972.
 255. Shore, S. A., O. Huk, S. Mannix, and J. G. Martin. Effect of panting frequency on the plethysmography determination of thoracic gas volume in chronic obstructive pulmonary disease. Am. Rev. Respir. Dis. 128: 54–59, 1983.
 256. Shore, S., J. Milic‐Emili, and J. G. Martin. Reassessment of body plethysmography technique for measurement of thoracic gas volume in asthmatics. Am. Rev. Respir. Dis. 126: 515–520, 1982.
 257. Siebens, A. A., N. A. Kirby, and D. A. Poulos. Cough following transection of spinal cord at C6. Arch. Phys. Med. Rehabil. 45: 1–8, 1964.
 258. Silvers, G. W., J. C. Maisel, T. L. Petty, G. F. Filley, and R. S. Mitchell. Flow limitation during forced expiration in excised human lungs. J. Appl. Physiol. 36: 737–744, 1974.
 259. Simon, G., N. B. Pride, N. L. Jones, and A. C. Raimondi. Relation between abnormalities in the chest radiograph and changes in pulmonary function in chronic bronchitis and emphysema. Thorax 28: 15–23, 1973.
 260. Sorli, J., A. Grassino, G. Lorange, and J. Milic‐Emili. Control of breathing in patients with chronic obstructive lung disease. Clin. Sci. Mol. Med. 54: 295–304, 1978.
 261. Spain, M. D., H. Siegel, and J. A. Bradess. Emphysema in apparently healthy adults. J. Am. Med. Assoc. 224: 322–325, 1973.
 262. Spiro, S. G., H. L. Hahn, R. H. T. Edwards, and N. B. Pride. An analysis of the physiological strain of submaximal exercise in patients with chronic obstructive bronchitis. Thorax 30: 415–425, 1975.
 263. Stalcup, S. A., and R. B. Mellins. Mechanical forces producing pulmonary edema in acute asthma. N. Engl. J. Med. 297: 592–596, 1977.
 264. Stânescu, D. C., D. Rodenstein, M. Cauberghs, and K. P. Van de Woestijne. Failure of body plethysmography in bronchial asthma. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 52: 939–948, 1982.
 265. Stead, W. W., D. L. Fry, and R. V. Ebert. The elastic properties of the lung in normal men and in patients with chronic pulmonary emphysema. J. Lab. Clin. Med. 40: 674–681, 1952.
 266. Steele, R. H., and B. E. Heard. Size of the diaphragm in chronic bronchitis. Thorax 28: 55–60, 1973.
 267. Stubbing, D. G., L. D. Pengelly, J. L. C. Morse, and N. L. Jones. Pulmonary mechanics during exercise in subjects with chronic airflow obstruction. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 511–515, 1980.
 268. Stubbs, S. E., and R. E. Hyatt. Effect of increased lung recoil pressure on maximal expiratory flow in normal subjects. J. Appl. Physiol. 32: 325–331, 1972.
 269. Suero, J. T., and C. R. woolf. Alterations in the mechanical properties of the lung during dyspnea in chronic obstructive pulmonary disease. J. Clin. Invest. 49: 747–751, 1970.
 270. Sugihara, T., C. J. Martin, and J. Hildebrandt. Length‐tension properties of alveolar wall in man. J. Appl. Physiol. 30: 874–878, 1971.
 271. Sullivan, C. E., M. Berthon‐Jones, and F. G. Issa. Remission of severe obesity‐hypoventilation syndrome after short term treatment during sleep with nasal continuous positive airway pressure. Am. Rev. Respir. Dis. 128: 177–181, 1983.
 272. Supinski, G. S., and S. G. Kelsen. Effect of elastase‐induced emphysema on the force‐generating ability of the diaphragm. J. Clin. Invest. 70: 978–988, 1982.
 273. Takishima, T., G. Grimby, W. Graham, R. Knudson, P. T. Macklem, and J. Mead. Flow‐volume curves during quiet breathing, maximum voluntary ventilation, and forced vital capacities in patients with obstructive lung disease. Scand. J. Respir. Dis. 48: 384–393, 1967.
 274. Tattersall, S. F., M. K. Benson, D. Hunter, A. Mansell, N. B. Pride, C. M. Fletcher, R. Peto, R. Gray, and P. R. R. Humphreys. The use of tests of peripheral lung function for predicting future disability from airflow obstruction in middle‐aged smokers. Am. Rev. Respir. Dis. 118: 1035–1050, 1978.
 275. Terry, P. B., R. J. Traystman, H. H. Newball, G. Batra, and H. A. Menkes. Collateral ventilation in man. N. Engl J. Med. 298: 10–15, 1978.
 276. Thurlbeck, W. M. Chronic Airflow Obstruction in Lung Disease. Philadelphia, PA: Saunders, 1976.
 277. Thurlbeck, W. M. Diaphragm and body weight in emphysema. Thorax 33: 483–487, 1978.
 278. Thurlbeck, W. M. Postmortem lung volumes. Thorax 34: 735–739, 1979.
 279. Thurlbeck, W. M., J. A. Henderson, R. G. Fraser, and D. V. Bates. Chronic obstructive lung disease. A comparison between clinical, roentgenologic, functional and morphological criteria in chronic bronchitis, emphysema, asthma and bronchiectasis. Medicine Baltimore 49: 81–145, 1970.
 280. Tierney, D. F., and J. A. Nadel. Concurrent measurements of functional residual capacity by three methods. J. Appl. Physiol. 17: 871–873, 1962.
 281. Ting, E. Y., R. Klopstock, and H. A. Lyons. Mechanical properties of pulmonary cysts and bullae. Am. Rev. Respir. Dis. 87: 538–544, 1963.
 282. Ting, E. Y., and H. A. Lyons. Pressure‐volume relations of lung and thoracic cage in pulmonary emphysema. J. Appl. Physiol. 16: 517–521, 1961.
 283. Tobin, M. J., T. S. Chadha, G. Jenouri, S. J. Birch, H. B. Gazeroglu, and M. A. Sackner. Breathing patterns. 2. Diseased subjects. Chest 84: 286–294, 1983.
 284. Turner, J. M., J. Mead, and M. E. Wohl. Elasticity of human lungs in relation to age. J. Appl. Physiol. 25: 664–671, 1968.
 285. Van Brabandt, H., M. Cauberghs, E. Verbeken, P. Moerman, J. M. Lauweryns, and K. P. Van de Woestijne. Partitioning of pulmonary impedance in excised human and canine lungs. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 55: 1733–1742, 1983.
 286. Von Basch, S. Über eine Function des Capillardruckes in den Lungenalveolen. Wien. Med. Bl. 10: 465–467, 1887.
 287. Wagner, P. D., D. R. Dantzker, V. E. Iacovoni, W. C. Tomlin, and J. B. West. Ventilation‐perfusion inequality in asymptomatic asthma. Am. Rev. Respir. Dis. 118: 511–524, 1978.
 288. Walsh, R. E., E. D. Michaelson, L. E. Harkerload, A. Mighelboim, and M. A. Sackner. Upper airway obstruction in obese patients with sleep disturbance and somnolence. Ann. Intern. Med. 76: 185–192, 1972.
 289. Webster, P. M., S. H. Loring, J. P. Butler, and F. G. Hoppin, Jr. Lung recoil during rapid vital capacity expirations simulated by gas compression. J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 49: 142–149, 1980.
 290. Wellman, J. J., E. R. McFadden, Jr., and R. H. Ingram, Jr. Density‐dependence of maximal expiratory flow rate before and after bronchodilators in patients with obstructive airways disease. Clin. Sci. Mol. Med. 51: 133–139, 1976.
 291. West, J. B., and J. K. Alexander. Studies on respiratory mechanics and the work of breathing in pulmonary fibrosis. Am. J. Med. 27: 529–544, 1959.
 292. Wittenborg, M. H., M. T. Gyepes, and D. Crocker. Tracheal dynamics in infants with respiratory distress, stridor and collapsing trachea. Radiology 88: 653–662, 1967.
 293. Wohl, M. E. B., J. Turner, and J. Mead. Static volume‐pressure curves of dog lungs—in vivo and in vitro. J. Appl. Physiol. 24: 348–354, 1968.
 294. Wood, T. E., P. McLeod, N. R. Anthonisen, and P. T. Macklem. Mechanics of breathing in mitral stenosis. Am. Rev. Respir. Dis. 104: 52–60, 1971.
 295. Woolcock, A. J., and P. T. Macklem. Mechanical factors influencing collateral ventilation in human, dog, and pig lungs. J. Appl. Physiol. 30: 99–115, 1971.
 296. Woolcock, A. J., and J. Read. Lung volumes in exacerbations of asthma. Am. J. Med. 41: 259–273, 1966.
 297. Woolcock, A. J., and J. Read. The static elastic properties of the lungs in asthma. Am. Rev. Respir. Dis. 98: 788–794, 1968.
 298. Woolcock, A. J., A. S. Rebuck, J. F. Cade, and J. Read. Lung volume changes in asthma measured concurrently by two methods. Am. Rev. Respir. Dis. 104: 703–709, 1971.
 299. Woolcock, A. J., N. J. Vincent, and P. T. Macklem. Frequency dependence of compliance as a test for obstruction in the small airways. J. Clin. Invest. 48: 1097–1106, 1969.
 300. Wright, P. H., A. Hanson, L. Kreel, and L. H. Capel. Respiratory function changes after asbestos pleurisy. Thorax 35: 31–36, 1980.
 301. Yernault, J. C., M. de Jonghe, A. de Coster, and M. Englert. Pulmonary mechanics in diffuse fibrosing alveolitis. Bull. Physio‐Pathol. Respir. 11: 231–244, 1975.
 302. Young, I. H., P. Corte, and R. E. Schoeffel. Pattern and time course of ventilation‐perfusion inequality in exercise‐induced asthma. Am. Rev. Respir. Dis. 125: 304–311, 1982.
 303. Zamel, N., I. Kass, and G. J. Fleischli. Relative sensitivity of maximal expiratory flow‐volume curves using spirometer versus body plethysmograph to detect mild airway obstruction. Am. Rev. Respir. Dis. 107: 861–863, 1973.
 304. Zapletal, A., E. K. Motoyama, L. E. Gibson, and A. Bouhuys. Pulmonary mechanics in asthma and cystic fibrosis. Pediatrics 48: 64–72, 1971.
 305. Zapletal, A., T. Paul, and M. Šamánek. Pulmonary elasticity in children and adolescents. J. Appl. Physiol. 40: 953–961, 1976.

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N. B. Pride, Peter T. Macklem. Lung Mechanics in Disease. Compr Physiol 2011, Supplement 12: Handbook of Physiology, The Respiratory System, Mechanics of Breathing: 659-692. First published in print 1986. doi: 10.1002/cphy.cp030337