Study observation:Find:Stdy:Lower GI tract:Nar:Proctosigmoidoscopy.rigid
study observation:find:stdy:lower gi tract:nar:proctosigmoidoscopy.rigid
Study observation:Finding:Duration of the study:Lower GI tract:Narrative:Proctosigmoidoscopy.rigid
study observation:finding:duration of the study:lower gi tract:narrative:proctosigmoidoscopy.rigid