title: Early chronic obstructive pulmonary disease: a clinical diagnosis.
mesh_terms: D000328:Adult; D004417:Dyspnea / Q000209:etiology; D005260:Female; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013997:Time Factors