title: Occurrence of methionine enkephalin in human placental villus.
mesh_terms: D004723:Endorphins / Q000378:metabolism*; D004744:Enkephalin, Methionine; D004745:Enkephalins / Q000378:metabolism*; D005260:Female; D006801:Humans; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011863:Radioimmunoassay
chemical_list: D004723:Endorphins; D004745:Enkephalins; D004744:Enkephalin, Methionine