Airway closure and lung volumes in surgical positions.
D000328:Adult; D000367:Age Factors; D004058:Diffusion; D006371:Helium; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009584:Nitrogen; D011187:Posture; D011650:Pulmonary Alveoli / Q000502:physiology; D001261:Pulmonary Atelectasis / Q000209:etiology; D011652:Pulmonary Circulation; D012119:Respiration; D013147:Spirometry; D013514:Surgical Procedures, Operative
D006371:Helium; D009584:Nitrogen