Routine urine examination during physical examination can understand the concentration and dilution functions of the kidneys and the acid-base regulation function, and also the presence of infection and bleeding. The routine examination contains the following items: 1, urine pH, it can understand the change of urine acidity and alkalinity. 2, urine white blood cell count, if the number of white blood cells is elevated, it indirectly indicates the existence of infection in the urinary tract. 3, urine red blood cell count, if the number of red blood cells is elevated, it indicates the existence of bleeding in the urinary system and requires further examination of the cause of bleeding. 4, urine specific gravity, it can understand whether there is dilution of urine or 5, urine bilirubin, it can understand whether bilirubin is elevated and whether there is a systemic bilirubin metabolism disorder. 6, urine nitrite, when there is an infection in the urine, especially when it is caused by enterobacteria, it can reduce nitrite to positive, which indirectly indicates the presence of enterobacteria infection in the urine. 7, protein, when the protein in the urine is elevated, it may be related to infection or kidney damage, further measurement of urine protein quantification is needed to exclude kidney damage.