saturation analysis of estrogen binding sites in cytosol of hec-1b cells labeled with [ 3h ] -e2 or [ 3h ] -estriol ( e3 ) , at concentrations ranging from 0.1-100 mm , showed two plateaus for e2 binding ( at about 20 and 60 nm ) but only one ( at about 40 nm ) for e3 , when dextran-coated charcoal was used to separate free and bound ligand .
C1383501
cytosol
C0007634
cells