Using homologous recombination , both EKLF alleles in murine embryonic stem ( ES ) cells were inactivated .
using homologous recombination , both eklf alleles in murine embryonic stem ( es ) cells were inactivated .
O O O O O B-DNA_molecule I-DNA_molecule O B-cell_line I-cell_line I-cell_line I-cell_line I-cell_line I-cell_line I-cell_line O O O