This article is based on determining plasma RNase activity of 200 normal persons aged 18 to 96 years. When a person is over 66, the plasma RNase activity will go up along with aggravation of physiological senescent. Fifty-eight persons who received diagnosis had chronic kidney disese. The plasma RNase level of deficiency of vital energy, deficiency of vital energy and the blood, def ciency of yang of kidney were 166±17, 305±18and 430±144 (10-2×unit/ml blood). But among seven cases of deficienciy of yin, The change was irregular, only two had increase.
