preincubation of cells with 1 mm uridine- ( 3 ) h for 5.5 hr , which resulted in a threefold increase in the total intracellular level of uridine nucleotides , had no effect on the subsequent incorporation of uridine- ( 14 ) c into cellular nucleic acids in the nucleus , whether present at a 1 microm or 1 mm concentration in the medium .
C0007634
cellular
C0007610
nucleus