Urethan Carcinogeiiesis and Nucleic Acid Metabolism: Factors Influencing Lung Adenoma Induction1
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چکیده
Experiments were performed (a) to test the validity of the proposal that urethan (ethyl carbamate) acts by virtue of its conversion to Ar-hydroxyurethan, and (6) to examine the general ity of the reported observations that pyrimidines interfere with lung adenoma formation by urethan. Conditions were obtained in adult and newborn SWR mice in which the average number of tumors per mouse increased linearly with urethan dose; the number of spontaneous tumors appearing in untreated mice was negligible compared with the number in duced by urethan. A comparison of urethan and Ar-hydroxyure-
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