4Hinton JM, Lennard-Jones JE, Young AC.A new method for studying gut transit times using radioopaque markers. Gut, 1969,10:842.
5Metalf A, Phillips S, Zinsmeister A, et al. Simplified assessmentof segmental colonic transit. Gastroenterology, 1987.92:40.
6Merker IS,Locher J,Burgio K,et al.Physiologic and psychologic characteristics of elderly population with chronic constipation.A m J Gastroenterol,1993,88(11):1854.
7Mollen R,Classsen,Kuijpers J.The evaluation and treatment of functional constipation.Scand J Gastroenterol,1997,32 Suppl 223:8.
8Ashraf W,Park F,Lof J,et al.An examination of the reliability of reported stool frequency in the diagnosis of idiopathic constipation.Am J Gastroenterol,1996,91(1):26.
9Jonathan M,Kevin C,Nicholas J,et al.Relation of colonic transit to functional bowel disease in older people:a population-based study-J Am geriatr Soc,1998,46:83.
6Van der shijp JRM, Kamm MA, nightingale JMD, et al. Radioisotope determination of regional colonic transit in severe constipation . comparison with radiopaque markers. Gut, 1993,34 (3) :402
7Stwar WF, Liberman JN, Scandler RS, et al. Epidemiology of constipation study in the unite states[ J ]. Am J Gastroenterol , 1999,94 (12 ) : 3530 - 3540
8Pare P, Ferrazzis, Ferrazzis, Thompson WG, et al. An epidemiology survey ofconspipation in Canada : difinattion , rates , demogeaphics , and predictors of health care seeking [ J ]. AmJ Gastroenterol , 2001,96 (11) :3130 -3137
9[1]Youssef NN,Di Lorenzo C.Childhood constipation:evaluation and treatment.J Clin Gastroenterol,2001,33(3):199
