they also were observed in cocultures of periosteum-free fetal metatarsal bones , with several extraneous sources of osteoclast precursors : yolk sacs and abdominal regions of 9- and 11-day-old embryos , fetal livers , and precultured mononuclear phagocytes isolated from the fetal liver .
C0015965
fetal
C1517162
fetal liver