NEUTRON EFFECTS ON ANIMALS 57 



by other workers. According to Chrom (5), animals given large doses of 

 X-raj's showed increased susceptibility to bacterial infections. Schwien- 

 horst, as reviewed by Warren and Dimlap (6), studied rats treated with 

 X-rays; he observed microscopically that, after heavy X-irradiation, the 

 reticulo-endothelial cells were injured and that phagocytosis by cells lining 

 the blood channels was decreased. Knott and Watt (7) found that the 

 leukocytes of normal and leukemic blood, irradiated with X-rays in vivo 

 or in vitro, showed a loss of their ability to phagocytose staphylococci. 

 It seems probable that the effects of neutron radiation in reducing resistance 

 to infections are similar to those produced by X-radiation. 



SUMMARY 



Resistance of mice to infection with hemolytic Staphylococcus aureus 

 was found to be reduced after exposure to 84.6 n. 



REFERENCES 



(1) Lawrence, J. H., Aebersold, P. C, and Lawrence, E. O., Proc. Xatl. Acad. 



^Vi.,22, 543 (1936). 



(2) Lawrence, J. H., in "Handbook of Physical Therapy", American Medical 



Association, Chicago (1938). 



(3) Lawrence, J. H.. and Tennant, R., J. Exptl. Med., 66, 667 (1937). 



(4) Enxs, T., Terrill, H. M., and Garner, J. M., Jr., Chapter 3. 



(5) Chrom, Sv. A., Acta Radiol., 16, 641 (1935). 



(6) Warren, S., and Dunlap, C. E., Arch. Path., 34, 562 (1942). 



(7) Knott, F. A., and Watt. W. L., Brit. Med. J., 1, 542 (1929). 



