KINETICS OF PRIMARY REACTIONS AND CHEMICAL PROTECTION 323 



been confirmed by direct chemical determination of nitrogen content 

 and it has also been established that autolysis is more energetic in 

 irradiated animals than in control ones and that their blood cannot 

 inhibit the antolytic process (Mkartychan, 1960). 



It is very important that protective agents (lack of oxygen, cysteine) 

 activate the antolytic processes. It has been, for instance, established 

 that cysteine and mercaptoethylamine activate autolysis, and speed 

 up radiation damage if they are systematically injected after irradiation, 

 in the case of internal damage caused by radioactive substances (cerium, 

 strontium) and by external radiation (Mkartychan, 1960). One could 

 therefore suppose that a lack of protective action and even a negative 

 effect of protective agents is due to the activation of the antolytic pro- 

 cess. This must be considered as the first step in the understanding of 

 the kinetics of primary reactions. 



REFERENCES 



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SuMARUKlov, G. V. (1958). Biophysics {Russ.) 3, 374. 



Tarusov, B. N. (1957). "Fiziko-himitcheskije mehanizmy biologitcheskogo deistvija 

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Tarusov. B. N. (1960). "Pervichnye mehanizmy biologitcheskogo deistvija ioniziru- 

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Zhuravlev, a. I. (1959). "Sbornik referatov po radiatsionnoi meditsine", Moscow. 



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DISCUSSION 



paribok: What was the experimental procedure: was oxygen under pressure 

 used or compressed air? 



TARUSOV: In case of extreme variations it was pure oxygen, while in other 

 experiments a mixture was used. 



PARIBOK: I should like to draw attention to one consideration. You have men- 

 tioned difficulties involved in work with oxygen under pressure when experi- 

 n^enting with mammals, due to the oxygen's toxicity. Actually many are well 

 acquainted with this difficulty, but symptoms appear only above 2 atm pressure, 



