background levels of chromosomal aberrations and sister-chromatid exchanges ( sces ) were determined in cho-99 cells , an oxygen-tolerant variant substrain of chinese hamster ovary ( cho-20 ) cells capable of stable proliferation under an atmosphere of 99 % o2/1 % co2 , a level of hyperoxia at which cultured mammalian cells normally can not survive .
C0037211
sister-chromatid exchanges
C0007634
cells