koller , 1977 , cell 12:101-107 ) with a fairly constant pitch but increasing numbers of nucleosomes per turn , until finally at 60 mm ( or else in approximately 0.3 mm mg++ ) a thick fiber of 250 a diameter is formed , corresponding to a structurally well-organized but not perfectly regular superhelix or solenoid of pitch approximately 110 a as described by finch and klug ( 1976 , proc .
C0007634
cell
C0028623
nucleosomes