Action of Radium and X-Rays upon Tumour Growth. 133 



Table VI. 



JSTiiinber 



Time of 



Growth of tumour in 

 X-rayed animals 

 compared with controls. 



General Remarks. 



of 



animals. 



exposure 



to 

 X-rays. 



Weeks after inoculation. 



Tumour growth. 



General condition. 







1 



2 



3 



4 



12 

 X-rayed 



12 

 controls 



5 minutes 

 daily for 

 1 week 



-13 



-03 



01 





No progressive growth of 

 tumour in the X-rayed 

 animals 



All X-rayed animals 

 except 4 died within 



^ 'WflfltQ 1 CnyTTl TOM 



rr WtrCJiBj J. o Ltl V 1 V tJU 



3 months. 



23 

 X-rayed 



19 

 controls 



1 minute 

 daily for 

 4 weeks 



1 -0 



0-76 



0-72 



0-36 



X-rayed animals grew 

 13 progressive tumours 

 10 disappearing tumours 



Controls grew 

 15 progressive tumours 

 4 disappearing tumours 



X-rayed animals well, 

 but body weight 

 increased 1 9 per cent, 

 less than the normals. 



14 

 X-rayed 

 15 



confcrols 



12 seconds 

 daily for 

 4 weeks 



0-8L 



0-73 



0-82 



0-73 



X-rayed animals grew 

 9 progressive tumours 

 5 disappearing tumours 



Controls grew 

 11 progressive tumours 

 4 disappearing tumours 



X-rayed animals well, 

 no record of body 

 weight, but vide 

 Table II, rows 2 and 3 . 



36 

 X-rayed 



33 

 controls 



2 seconds 

 daily for 

 4 weeks 



1 -25 



1 -23 



1 -05 



0-79 



X-rayed animals grew 

 17 progressive tumours 



19 disappearing tumours 

 Controls grew 



20 progressive tumours 

 13 disappearing tumours 



Animals well, body 

 weight increase same 

 as normals. 



increased more than normally. When the tumour growth figure 0"73 at the 

 fourth week is compared with the figure 0"55 at the fourth week in Table V, 

 it seems rational to attribute this difference to the shghtly stimulating effect 

 which small doses have , been shown to. have upon the malignant cells {vide. 

 Tables I and IV). 



Discussion of Results. 



Since the attempt has been made throughout these investigations to 

 express the results quantitatively, it remains to consider to what extent the 

 observed differences in the rate of growth of the animals and of the tumours 

 are significant. In Section A, the matter which calls for comment is that 

 the rate of growth of tumour was 1"35 times that of the normal when the 

 tumour cells had previously received a small dose of beta-rays. The number 

 of animals used, viz., eight, is not large enough to consider the matter 

 established, but, when the experiment is done under slightly different 

 conditions with the same dose of rays, a similar increase occurs in the rate of 



VOL. XCII. — B. M 



