title: Study of the relationship between roentgenfilm densitometry and linear lung expansions.
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D006801:Humans; D008168:Lung / Q000033:anatomy & histology*; D008297:Male; D008451:Maximal Voluntary Ventilation; D011187:Posture; D012119:Respiration