Clinical renal function can be judged from the following aspects: 1, symptoms and signs, renal function is not good patients with yellow or pale, nausea, vomiting, not want to eat, fatigue, double lower extremity edema, or even generalized edema, etc., blood pressure is elevated when measuring blood pressure, and there are percussion pains in both kidneys, etc. 2, laboratory tests, routine blood shows that hemoglobin and red blood cells are lower than normal suggesting anemia. In the biochemical examination of renal function test, urea nitrogen, creatinine increase suggests that the renal function is impaired. Decrease in carbon dioxide binding rate suggests metabolic acidosis, and increase in potassium suggests hyperkalemia.3. Special examination, renal ultrasound or CT suggests renal atrophy, decrease in renal volume, decrease in renal blood flow, etc., which suggests renal damage.