title: Single-contrast or double-contrast barium enema: a historical and philosophical perspective.
mesh_terms: D001466:Barium Sulfate; D003108:Colonic Diseases / Q000000981:diagnostic imaging*; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D004733:Enema; D006801:Humans; D011856:Radiographic Image Enhancement / Q000379:methods*
chemical_list: D001466:Barium Sulfate