8Rao SS, Camilleri M, Harker WI., et al. Evaluation of gas- trointestinal transit in clinical practice: position paper of the American and European Neurogastroenterology and Motility Societies[J]. Neurogastroenterol Motil, 2011, 23(1): 8-23.
9XU Hui-min, HAN Jia-gang, NA Ying, et al. Colonic transit time in patient with slow-transit constipation: comparison of radiopaque markers and barium suspension method[J]. Eur J Radiol, 2011, 79(2) : 211-213.
