title: [Chronic constipation -- measurement of colonic transit time with radio-opaque markers].
mesh_terms: D002908:Chronic Disease; D003106:Colon / Q000000981:diagnostic imaging*; D003248:Constipation / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004867:Equipment Design; D057918:Fiducial Markers; D005772:Gastrointestinal Transit; D006801:Humans; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods*