title: Stem cells. Mixing species--and crossing a line?
authors: Nell
authors: N
authors: Boyce
mesh_terms: D000818:Animals; D035843:Biomedical Research; D004622:Embryo, Mammalian / Q000166:cytology*; D006801:Humans; D051379:Mice; D033581:Stem Cell Transplantation / Q000941:ethics / Q000379:methods; D014183:Transplantation, Heterologous