Identification of Human Blood on the Basis of the Fibrin Plate Method

The method of identifying human blood is studied from the standpoint of the fibrinolytic enzyme system by means of the "fibrin plate method" and the following results are obtained: 1) "Fibrin plate method" is, in the point of its sensitivity and speciesspecificity, one of the most excellent methods for the identification of human blood. 2) A small amount of the blood stains left standing as long as for 5 to 30 years can serve in the determination of the human blood. 3) Putrefied fluid blood does not demonstrate fibrinolysis. 4) Blood stains absorbed in various objects can also he identified whether they are of the human origin or not. 5) The pieces of cloth stained with human blood give positive fibrinolysis even after four washings with soap or after heating at 100°C for one hour. On the other hand, positive results are obtained with the pieces of cloths after three washings by benzidine test and with the physiological saline-extracted solution obtained after two washings of pieces of cloth, by precipitation test. 6) Proactivator has been found to contain globulin fraction in human serum protein. 7) The blood type can be determined with the same materials previously examined by the "fibrin plate method".