The section below the needle is the needle stem.
Syringes are a common medical device, as early as the 15th century, the Italians Catinel proposed the principle of syringes, mainly with a needle to extract or inject gases or liquids.
Syringes can also be used for medical devices, containers, such as some chromatography in the scientific instruments injected through a rubber diaphragm.
Overview
The emergence of the syringe was an epoch-making revolution in the field of medical devices, and the 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 gas into or withdraw it from areas that are inaccessible by other means. The liquid or gas is drawn through the hole in the front of the barrel when the mandrel is withdrawn, and is squeezed out when the mandrel is pushed in.