title: Etiology and epidemiology of ulcerative colitis.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003093:Colitis, Ulcerative / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007223:Infant; D008297:Male; D008875:Middle Aged; D014481:United States