title: Helicobacter pylori and the etiology of duodenal ulcer: necessary but not sufficient.
authors.forename: M
authors.initials: M
authors.lastname: Feldman
mesh_terms: D004381:Duodenal Ulcer / Q000209:etiology* / Q000382:microbiology; D005260:Female; D016481:Helicobacter Infections / Q000150:complications*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D012307:Risk Factors