title: [Status of ventilation and perfusion in late middle-aged chronic bronchitis patients].
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001991:Bronchitis / Q000503:physiopathology*; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014692:Ventilation-Perfusion Ratio
vernacular_title: Sostoianie ventiliatsii i perfuzii u bol'nykh khronicheskim bronkhitom v pozhilom vozraste.