title: The stem cell problem in the fetus.
mesh_terms: D000818:Animals; D001810:Blood Volume; D001854:Bone Marrow Cells; D002465:Cell Movement; D002642:Chick Embryo; D003238:Connective Tissue / Q000196:embryology; D004920:Erythropoiesis; D005260:Female; D005333:Fetus; D006412:Hematopoietic Stem Cells; D006801:Humans; D007231:Infant, Newborn; D007962:Leukocytes / Q000166:cytology; D008099:Liver / Q000196:embryology; D008102:Liver Circulation; D008214:Lymphocytes; D008648:Mesoderm; D051379:Mice; D011247:Pregnancy; D014817:Vitelline Membrane