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Syringes are a common medical appliance. As early as the 15th century, the Italian Catinel proposed the principle of syringe. It is mainly used to extract or inject gas or liquid with a needle.
Syringes can also be used for medical devices, containers, such as some chromatography in which scientific instruments are injected through a rubber diaphragm.
Overview
The emergence of the syringe was an epochal revolution in medical devices. This process of extracting and injecting a gas or liquid with a needle is called injection.
The syringe consists of a barrel with a small hole in the front and a matching piston mandrel, which is used to inject small quantities of liquid or its into or withdraw it from areas that are inaccessible by other means, the liquid or gas being drawn in through the hole in the front of the barrel when the mandrel is withdrawn, and squeezing out the liquid or gas when the mandrel is pushed in.
According to medical history books, the first form in which the syringe appeared was the enema. China's Han Dynasty physician Zhang Zhongjing in his "Treatise on Typhoid Fever" (written in 219 A.D.), "Yangming full chapter" wrote: "Yangming disease, since the sweating, if sweating, urination self-liberation, this is the fluid within the exhaustion of the hard can not be attacked, when it is necessary to want to stool, it is desirable to honey decoction guide and through the. If the root of the earth melon and pig bile, can be a guide.
"In the book of the "pig bile formula" in the article and clearly pointed out: "a large pig bile, laxative juice and a little vinegar, in order to instill the Valley Road (anus), such as a food hectare, when the stool, out of the pastime of the bad things very effective." How to "irrigate the valley road" it.