title: Inverse association between appendicectomy and ulcerative colitis.
authors.forename: Morten
authors.initials: M
authors.lastname: Frisch
mesh_terms: D001062:Appendectomy / Q000706:statistics & numerical data; D003093:Colitis, Ulcerative / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D012307:Risk Factors