Acute abdomen.
D000006:Abdomen, Acute / Q000000981:diagnostic imaging*; D000328:Adult; D004381:Duodenal Ulcer / Q000150:complications; D006801:Humans; D010439:Peptic Ulcer Perforation / Q000150:complications; D011027:Pneumoperitoneum / Q000000981:diagnostic imaging* / Q000209:etiology; D011859:Radiography