154 



Ribose nucleic acid (cont'd.) 



nuclear origin, 76 



protection against radiation, 



36 



relation to DNA, 78 



relation to protein synthesis, 



73 



role in cell growth, 70 



role in mitosis, 70, 78 



thymus of irradiated rats, 81 

 Ring Structure 



effect on radiation response, 



12 



Salmonella 



transduction, 141 



Sea urchin 



dispersion of sperm nuclei, 

 144 



effects of radiation on respi- 

 ration of eggs and sperm, 

 136 



isolation of nucleoprotein in 

 sperm, 149 



Sedimentation velocity 



criterion of response of 

 radiation, 131 



Sensitive volume, 21 



Sensitized fluorescence 



distance of occurrence, 19 



Sequential blocking technique 

 oxidative phase of carbo- 

 hydrate metabolism , 69 



Serum albumin 



effects of irradiation, 34 



Serum lipoprotein metabolism 

 effects of radiation, 93 



Sex difference 



postirradiation accumula- 

 tion of citric acid in liver of 

 rats, 93 



Shielding 



effect on DNA and RNA in 

 thymus, 81 



Solubility 



role in radiosensitivity, 8 



Soret band, 39 



Sperm 



effect of radiation in vivo, 42 



Spleen 



breakdown of 5-adenylic 



acid, 100 



endogenous respiration, 88, 



89 



enzyme inhibition in vivo, 87 



Spleen (cont'd.) 



geographic relationships of 



cells, 105 



inhibition of citric acid forma- 

 tion, 89 



isolation of protective frac- 

 tion, 143 



mouse, 142 



protective action, 142 



radiation-induced involution, 



109 



relation of involution to DNA 



synthesis postirradiation, 93, 



99 

 Streptomycin 



radiosensitivity of trans- 

 forming principle, 4 

 Suballeles 



response to irradiation, 114 

 Sub-genes 



response to irradiation, 114 

 Substrate 



effect on radiation response 



of E. coll, 54 

 Succinate, 87 

 Succinic dehydrogenase, 87 



radiation response in dry or 



wet state, 14 

 Sulfanilamide acetylation 



in irradiated rats, 50 

 Sulfhydryl groups 



reversibility of radiation 



response, 12 



role in radiation response, 87 



Temperate virus, 138 

 Temperature 



effects on cross-section and 



inactivation volume, 8 



effects on E. coli, 57 



effects on radiation response 



of protein, 10 



effects on radiosensitivity of 



phage, 133 

 Theoretical approach to Radio- 

 biology, 2 

 Thymine 



ionic yield, 38 

 Thymus 



effects of hydrocortisone on 



cell population, 106 



effects of HN^ compared with 



radiation, 96 



effects of radiation on DNA 



and RNA, 63 



