however , rms cells grown in the presence of either retinoic acid ( 5 microns ) , phorbol ester ( 1 nm ) , prostaglandin e1 ( 10 ng/ml ) , or 2 % fetal calf serum gave rise to myotubes with a biochemical shift in the creatine kinase isoenzyme pattern from the embryonic to the mature skeletal muscle form .
C0035412
rms
C1704336
myotubes