4Fenger C, Knolh M. The anal transilional zone. A scanning and transmission electron microscopic investigation of mucosal surface. Uhrastruct Path, 1981.2: 163.
5Fenger C, Lyon H. Endocrine cell and melanin containing cell in the anal canal epithelium. Histochemical J. 1982.14(4) :631.
7Gibbons CP,Trwbridge EA,Bannister JJ.et al. Rolc of anal cushions in maintaing conlinence. I.ancct. 1986. 19:886.
8Read 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.
9Mortensen PE,Olsen J,Pederson IK.et al. A randomized study on hemorrhoidectomy combincd with anal dilatation. Dis Colon Rectum,1987,30:255.
10Terramoto T. Park AG, Swash M. Hypertrophy of the external anal sphincter in hemorrhoids:a histomeric study.Gut.1981,22:45.