[What are the necessary preoperative tests of gastric ulcer?].
D001706:Biopsy; D003581:Cytodiagnosis; D005750:Gastric Juice; D005773:Gastroscopy; D006801:Humans; D011300:Preoperative Care; D011859:Radiography; D013270:Stomach / Q000000981:diagnostic imaging; D013276:Stomach Ulcer / Q000175:diagnosis / Q000601:surgery*