Large biochemistry tests usually have to be registered with the Department of Internal Medicine. Large biochemical test items include human trace elements, such as calcium, magnesium, sodium, potassium, aluminum ions, etc., as well as aminotransferases, bilirubin, globulin, total protein, albumin and other indicators, which can reflect the existence of electrolyte disorders, acid-base imbalance, as well as to understand the normal function of the liver and kidneys, which are within the scope of the Department of Internal Medicine, and therefore need to be listed in the Department of Internal Medicine. Doing a large biochemistry test need to pay attention to a week before the large biochemistry test should pay attention to diet, diet should be light, avoid eating high protein, high fat, high calorie and high sugar food; do not do large biochemistry test 24 hours before strenuous exercise, do not drink alcohol; do large biochemistry test 6 to 8 hours before the blood test, do not drink water, eat. Large biochemistry is a relatively important examination of our body, which can reflect the changes of multiple organ systems, and is conducive to the timely discovery of the body’s problems.