the uds level of lung-derived cells ( lung cells ) , as measured with hydroxyurea-resistant incorporation of [ 3h ] thymidine into cellular dna in the presence of 4-nqo , was at least threefold lower than levels in cells from skin , intestine , kidney , liver , and brain , when compared at equitoxic doses of 4-nqo of equimolar binding of 4-nqo to dna autoradiographic studies also revealed that the percentage of uds-positive nuclei in lung cells was about one-fifth of other cell types .
C0007610
nuclei
C0007634
cells