STUDIES IN THE REGENERATION OF BLOOD 253 



SUMMARY OF RESULTS 



Hemorrhages of approximately one-third of the estimated total 

 blood volume can be borne by albino rats without interfering with 

 complete recovery. When one-half or more of the blood was removed 

 by hemorrhage, death ensued. The criteria used in judging blood 

 regeneration in the rat were the return of the number of erythrocytes 

 and the percentage of hemoglobin to the values noted before the animal 

 had sustained any loss of blood. 



By varying the diet from elimination of one factor to elimination of 

 all but one factor therein, the speed of regeneration of blood was 

 changed, but with each diet the organism replenished its normal supply 

 of blood to the original values for red cells and hemoglobin. 



Protein permitted more rapid blood regeneration than either carbo- 

 hydrate or fat when fed as a sole nutrient (2.0 grams daily) . 



The diets of vitamin-rich food, even in very small amounts, gave 

 somewhat more speedy regeneration than any other diet containing 

 one food factor only. 



This study of blood regeneration has not covered the effect of iron on 

 blood formation. Work on this phase of the problem is now being 

 carried out. 



I desire to express my sincere thanks to Prof. Lafayette B. Mendel 

 who outlined this problem, for his suggestions and interest throughout 

 the investigation. 



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