title: Gastric acid state and gastroduodenal changes in chronic obstructive pulmonary disease.
mesh_terms: D000328:Adult; D000368:Aged; D004382:Duodenitis / Q000209:etiology; D005744:Gastric Acid / Q000378:metabolism*; D005756:Gastritis / Q000209:etiology; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000150:complications / Q000503:physiopathology*; D008875:Middle Aged; D010437:Peptic Ulcer / Q000209:etiology