title: The clinical study of upper gastrointestinal bleeding.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004724:Endoscopy; D005260:Female; D005336:Fiber Optic Technology; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged