The syringe is a common medical instrument. As early as the 15th century, the Italian Catinel proposed the principle of the syringe. It is mainly used to extract or inject gases or liquids with a needle. Syringes can also be used for medical devices, containers, such as some chromatography in the scientific instruments injected through the rubber diaphragm. The emergence of needleless syringes was an epoch-making revolution in the field of medical devices. The emergence of syringes was an epoch-making revolution in the field of medical devices. The process of extracting or injecting a gas or liquid with a needle is called injection. A syringe consists of a barrel with a small hole in the front and a matching piston mandrel, which is used to inject small amounts of liquid or gas into or withdraw it from areas that are inaccessible by other means. The liquid or gas is sucked in through the hole in the front of the barrel when the mandrel is withdrawn, and is squeezed out when the mandrel is pushed in.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 earth melon root and large pig bile, can be a guide." Scientists have developed a new way to inject drugs without needles, using a high-speed, high-pressure jet to inject drugs through the skin. This method could one day end the days when today's injections hurt. Scientists unveiled the needleless injector on May 26th. Much like the injection device in the movie Star Trek, it can inject various doses of medication into different depths of the skin according to pre-established procedures. For patients who suffer from "needle phobia", this innovative injector could be very popular in the future, as it does not cause pain to the patient. Often, such patients don't even get vaccinated due to their fear of needles.