3Fenger C, Knolh M. The anal transilional zone. A scanning and transmission electron microscopic investigation of mucosal surface. Uhrastruct Path, 1981.2: 163.
4Fenger C, Lyon H. Endocrine cell and melanin containing cell in the anal canal epithelium. Histochemical J. 1982.14(4) :631.
6Gibbons CP,Trwbridge EA,Bannister JJ.et al. Rolc of anal cushions in maintaing conlinence. I.ancct. 1986. 19:886.
7Read MG, Read NW, Haynes WG. et al. A prospective study of the effect of haemorrhoidectomy on sphinctcr function and faecal continence. Br J Surg. 1982,69:396.
8Mortensen PE,Olsen J,Pederson IK.et al. A randomized study on hemorrhoidectomy combincd with anal dilatation. Dis Colon Rectum,1987,30:255.
9Terramoto T. Park AG, Swash M. Hypertrophy of the external anal sphincter in hemorrhoids:a histomeric study.Gut.1981,22:45.
10Buffa R.Capella C,Fontana P.et al. Types of endocrine cells in the human colon and rectum. Cell Tiss Res.1978,192:227.