what are ** fissures?(肛裂)

n****8

What are ** fissures?
An ** fissure is a cut or tear occuring in the anus (the opening through which stool passes out of the body) that extends upwards into the ** c**. Fissures are a common condition of the anus and ** c** and are responsible for 6-15% of the visits to a colonic and rectal (colorectal) surgeon. They affect men and women equally and both the young and the old. Fissures usually cause pain during bowel movements that often is severe. Anal fissure is the most common cause of rectal bleeding in infancy.
Anal fissures occur in the specialized tissue that lines the anus and ** c**, called anoderm. At a line just inside the anus--referred to as the ** verge or intersphincteric groove--the skin (dermis) of the inner buttocks changes to anoderm. Unlike skin, anoderm has no hairs, sweat glands, or sebaceous (oil) glands and contains a larger number of somatic sensory nerves that sense light touch and pain. (The abundance of nerves explains why ** fissures are so painful.) The hairless, gland-less, extremely sensitive anoderm continues for the entire length of the ** c** until it meets the demarcating line for the rectum, called the dentate line. (The rectum is the distal 15 cm of the colon that lies just above the anus and rectum and just below the sigmoid colon.)

n****8

Is there anybody know it ?I'm so sorry.If so ,I will never put them on .
I like English,I want to find somebody who has the same hobby.It seems so difficulty.OhOh.

爱**灯

:@ I  don't  know  english , can  you  write  in  chinese?  :lol:  I'm a chinese , I  hope rending topic of chinese , OK[/color]?:'(

k****n

:L 英语比刚毕业是退步了