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Barbara E. Holmes 



particular stage of regeneration. Table I shows that a large 

 increase in fat content occurs soon after hepatectomy and 

 persists for 2 days. It is not particularly connected with any 

 stage of the mitotic cycle and may merely be a sign of altered 

 or curtailed activity of the liver. The fat was extracted and 

 estimated by the hydroxylamine and ferric chloride method of 

 Stern and Shapiro (1953). 



Table I 



The respiration of the liver was known to be higher after 

 hepatectomy, and Schw^artz and Barker (1954) had measured 

 it at different times after the operation. Table II shows 

 Itzhaki's data, which can be considered in connection with 

 the synthesis and mitosis curves. The respiration is already 

 very high at the beginning of synthesis, is unaltered during 

 the period of high mitosis and continues to be high for 3 days. 

 The respiration was measured in a Warburg apparatus in the 

 presence of an excess of glucose. 



The oxidation of glucose itself was estimated by measuring 

 the specific activity of COg derived from the oxidation of 

 glucose uniformly labelled with ^^C. The COg was trapped in 

 potassium hydroxide, sodium carbonate was added as carrier 

 and the carbonate precipitated as the barium salt, the weight 

 of the barium salt being always about 100 mg. The factor for 

 converting the counts, estimated to the total count, was known. 



