title: Role of colonoscopy in patients with unexplained melena: analysis of 53 patients.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003108:Colonic Diseases / Q000175:diagnosis*; D003110:Colonic Neoplasms / Q000175:diagnosis; D003113:Colonoscopy; D003424:Crohn Disease / Q000175:diagnosis; D004241:Diverticulum, Colon / Q000175:diagnosis; D005260:Female; D005336:Fiber Optic Technology; D006801:Humans; D007417:Intestinal Polyps / Q000175:diagnosis; D008297:Male; D008551:Melena / Q000175:diagnosis* / Q000209:etiology; D008875:Middle Aged; D012189:Retrospective Studies