REFERENCES 407 



the mitotic phase ratio, and the percentage of degenerating cells should 

 be extended to mammalian tissue. 



TABLE 3 



Degree of 

 Radiations Tested Additivity Reference 



Gamma; fast neutron (exposure Complete Zirkle (72) 



of about 1 hr) 

 Gamma; fast neutron (exposure Incomplete Mitchell (49) 



of 24-48 hr) 

 Beta; gamma Incomplete Raper and Barnes 



(57) 



It has been found that sensitivity of the mammal to x-rays can be 

 modified in various ways (increased resistance of newborn at low tem- 

 perature, under anoxia, fortified with cysteine, etc., and decreased re- 

 sistance of adults at low temperature). Such modification of radiosen- 

 sitivity should be attempted for neutron exposures. The response may 

 be similar under some conditions and may differ under other conditions 

 (as, for example, protraction or fractionation). 



REFERENCES 



1. Abelson, P. H., and P. G. Kruger, Cyclotron-induced radiation cataracts, Science, 

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2. Aebersold, P. C, and John Lawrence, The physiological effects of neutron rays, 

 Ann. Rev. Physiol, 4: 25-48, 1942. 



3. Brues, A. M., Radiation sickness, Med. Phys., 2: 778-781, 1950. 



4. Catcheside, D. G., and D. E. Lea, The effects of ionization distribution on 

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5. Catcheside, D. G., Survey of effects of radiation on chromosomes, Brit. J. Radiol., 

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6. Chase, Herman, Henry Quastler, and Lester Skaggs, Biological evaluation of 

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7. Dowdy, A. H., and NEPA Medical Advisory Panel, Tabulation of available 

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8. Dowdy, A. H., L. R. Bennett, and Sarah M. Chastain, Study of the effects of 

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 radiation, UCLA-55, Jan. 3, 1950. Nuclear Sci. Abstr., No. 2121, Vol. 4, No. 8, 

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9. EUinger, Friedrich, The Biologic Fundamentals of Radiation Therapy, Elsevier 

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 1945. 



11. Ellinger, Friedrich, Influence of dose fractionation on the lethal X-ray effect 

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