both nf and xp cells tolerate up to 200 microm zncl2 in the growth medium , upon addition of zncl2 ( 200 microm ) to monolayer cultures , both nf and xp cells showed similar kinetics for the induction of mt synthesis : within 7 hours the mt synthesis rate rose from a low , marginally detectable rate to a maximal rate at least 50-fold greater than the basal rate .
C0016030
nf
C0007634
cells