THE MODIFICATION OF THE RADIATION 

 RESPONSE BY SHIELDING PROCEDURES 



L. F, Lamerton and E. H. Belcher 

 Physics Dept., Institute of Cancer Research, Royal Cancer Hospital, London 



The purpose of the present communication is to give a very brief review of 

 progress of work carried out in the Physics Department of the Institute of 

 Cancer Research on the radiation response of the young growing rat, with 

 and without various shielding procedures. Throughout the work the 

 endeavour has been to use doses of radiation less than the lethal dose, so 



20 



15 



10 



5 



O) 260 



2¥0 

 220 



\ 200 



^ 



^180 



■ ^ 160 



no 



120 

 100 



Haemoglobin (g Tfi/iOO ml w/io/e b/ooo/j 



Lymphocytes [lO^/jrcxvc') 



Polymorphs [/^y tutti'^ ) 



Figure 1. Changes in growth 

 rate and blood picture follow- 

 ing whole-body X-irradiation 

 (450?) to young rat {albino 

 strain) 



-5 



5 



10 15 20 25 30 

 Days after /rradiation 



that the irradiated animal can be studied in the recovery period as well as 

 in the phase of development of damage. We regard this as an important 

 aim if one is concerned with the problem of the mitigation of the effects of 

 large-volume exposure, since there are undoubtedly a number of mechan- 

 isms concerned in the radiation response, and it is important to know at 

 which stage a particular procedure is effective. 



The young growing rat proves to be, from a number of points of view, a 

 suitable material for studying the various phases of the radiation response 



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