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DISCUSSION 



Gray: Clearly, as Dr. Hollaender has suggested, there are two possible 

 protection mechanisms which we must somehow try to separate: 

 chemical protection, which intercepts the radicals as they are formed 

 along the track of the particles; and a mechanism which operates by 

 changing the cell in its reactions to the radicals that are produced. I 

 would like to ask Dr. Hollaender if he has any protection data relating 

 to other types of ionizing radiation, particularly the more densely 

 ionizing particles, such as neutrons and alpha particles, which produce 

 what seem to be identical forms of cytological and other damage to the 



