720 ADVENTURES IX RADIOISOTOPE RESEARCH 



One milligram of the acid-soluble organic P of the sarcoma, which is decomposed 

 in the course of 180 min hydrolysis, shows nearly the same content of radio - 

 actively labelled phosphorus, 2 hr. after injection, as 1 mgm of free P of the 

 sarcoma. Almost all molecules of the above mentioned acid-soluble phosphorus 

 compounds, of the sarcoma are thus renewed in a period of 2 hr. Irradiation with 

 a dose of 2000 r does not produce any detectable effect on the rate of renewal 

 of the acid-soluble P compounds of the sarcoma. 



