Fig. 5. Difference in trypan b]ue diffusion between control and irradiated piece of a cow 

 aorta. Both sections are taken from the same region of the same aorta. 



Upper control; loiver irradiated with 2,000 r. 



O 



o 



,^.. 



Fig. 7. Rat aortae; first three, non-irradiated controls; last two, total-body irradiation 

 with 3,000 r; all were injected with 0-7 ml 1% Congo-red solution and kilkd 30 minutes 

 after injection. 



