As a systematic discipline, internal medicine has a complete theoretical system, although it is practical. It studies the human body as an independent system. Because of the intervention of human factors, surgery should think of the human body as an open system more often.

Guiding opinions:

Internal medicine can be divided into: respiratory medicine, digestive medicine, cardiovascular medicine, neurology, endocrinology, hematology, infectious diseases, pediatrics and so on. Surgery is mainly divided into general surgery, cardiothoracic surgery, urology, orthopedics, neurosurgery, burns, plastic surgery, microsurgery and so on.