Haematemesis and melaena:  a survey.
D003625:Data Collection; D006396:Hematemesis / Q000209:etiology*; D006801:Humans; D008551:Melena / Q000209:etiology*; D010437:Peptic Ulcer; D010438:Peptic Ulcer Hemorrhage
HEMATEMESIS/etiology and pathogenesis; MELENA/etiology and pathogenesis; PEPTIC ULCER/hemorrhage