title: A study of infective and other factors in exacerbations of chronic bronchitis.
mesh_terms: D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000032:analysis; D001424:Bacterial Infections / Q000150:complications*; D001991:Bronchitis / Q000209:etiology*; D004804:Eosinophils; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013183:Sputum / Q000166:cytology / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D014777:Virus Diseases / Q000150:complications*
chemical_list: D000907:Antibodies, Bacterial