anus, that is, anatomical anal canal. Traditional Chinese medicine calls the anus "the door of the soul". People call it an asshole. Spirit communicates with dregs, transmitting dregs, hence the name "ass" or "donkey". Huangdi Neijing said: "The soul gate is also an envoy of the five internal organs, and Shui Gu cannot hide for a long time." Zhang Jingyue, a physician in the Ming Dynasty, said: "Although the dross is solid in its diarrhea, the rise and fall of dirty qi also depends on it, so it is made by the five internal organs." That is to say, the opening and closing of the soul door (anus) depends on the control of the mind, the adjustment of liver qi, the elevation of temper, the declaration of lung qi and the fixation of kidney qi, so as not to lose its normality. From the discussion of the above literature, we can know that the anus is the place where the human body eliminates turbid qi and turbid qi to regenerate, which is not only controlled by dirty qi, but also affects dirty qi.

The anus is the end of the anorectum and an organ of the human body, which is located between the buttocks. The anus has three main functions.

(1) release the waste gas in the human body, that is, fart (also known as bed warming gas).

(2) excreting wastes from the human body, that is, excreting remains.

(3) Gating function: preventing intestinal contents from involuntarily overflowing, and preventing foreign bodies such as gas and liquid from entering the intestinal cavity.

The anus needs to be cleaned frequently. The common diseases are hemorrhoids, anal fissure, proctoptosis, anal fistula, anal sinusitis, anal edema and perianal abscess.

When it comes to anus in life, it is often difficult for people to talk about it, but it is only a very important part of human body function. In Chinese medicine, the anus is also called "soul gate", which is used for the five internal organs. "Shi" has the meaning of envoy in ancient times, that is, the lesions of the five internal organs can be reflected in the anus. It is also said that "Shui Gu can't hide for a long time", which shows that the anus has the function of controlling and defecating, and this ability of controlling and defecating is coordinated with the function of "drying" and conduction of the large intestine, which is dominated by the five internal organs. When the anus defecates, it will naturally contract, and with the discharge of gas (fart), it will not bring out fecal residue. This is because the anus has very good sensory control ability, and the closed anus has the function of resisting bacteria and foreign bodies from entering the human body. The skin of the anus contains a large number of lymphocytes, and its self-cleaning ability and contraction ability are incomparable with those of other parts of the human body. In addition, the structure of the muscle and blood vessels in the anus is very ingenious, and the coordination between them plays a good role in fixing the abdominal organs of the human body. Without anus or poor anal function, it will bring a lot of inconvenience to people's lives.

anal structure

the anus is the opening at the end of the digestive tract to the outside world. Usually, it is closed in a longitudinal direction, and it expands in a circular shape when defecating, with a diameter of about 2~3 cm. The skin of the anus is black, and there are bags, sweat glands and sebaceous glands in the skin, which often form many radial folds due to muscle contraction.