chromatin from spleen cells of normal , non-immunized mice and from mice 3 days after immunization with human immunoglobulin g was fractionated at increasing salt concentrations into three fractions : 0.35 m nacl-soluble , 2 m nacl-soluble and a residual fraction , dissociated in 2 m nacl/5 m urea .
C0008546
chromatin
C0007634
cells