Ten clones were picked from cultured colonies of CaEs-17 cell line and developed to a subcell line. The values of SF2 were measured for each subcell line.

• 从我国自行建株的人食道癌细胞系CaEs－17野生型中分离出两株放射抗拒的亚系克隆7和克隆10，其SF2值分别为0.；41、0