title: Helicobacter pylori infection--a common worldwide environmental risk factor for gastric cancer?
authors.forename: P
authors.initials: P
authors.lastname: Sipponen
mesh_terms: D005756:Gastritis / Q000453:epidemiology / Q000382:microbiology; D016481:Helicobacter Infections; D016480:Helicobacter pylori; D006801:Humans; D015994:Incidence; D012307:Risk Factors; D012923:Social Class; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000382:microbiology*