Locating the source of gastrointestinal bleeding.
D004941:Esophagitis / Q000150:complications; D005756:Gastritis / Q000150:complications; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis*; D006801:Humans; D007441:Intubation, Gastrointestinal; D010437:Peptic Ulcer / Q000150:complications