Letter: Role of infection in chronic bronchitis.
D000402:Airway Obstruction / Q000150:complications / Q000209:etiology; D001991:Bronchitis / Q000150:complications / Q000209:etiology*; D002908:Chronic Disease; D006192:Haemophilus Infections / Q000150:complications; D006801:Humans; D008168:Lung / Q000503:physiopathology; D009175:Mycoplasma Infections / Q000150:complications; D012141:Respiratory Tract Infections / Q000150:complications*; D013147:Spirometry