Study observation:Find:Stdy:Lower GI tract:Nom:Proctosigmoidoscopy.rigid
study observation:find:stdy:lower gi tract:nom:proctosigmoidoscopy.rigid
Study observation:Find:Stdy:Lower GI tract:Nom:Proctosigmoidoscopy.rigid
study observation:find:stdy:lower gi tract:nom:proctosigmoidoscopy.rigid