title: Methionine-enkephalin deficiency in brains of patients with Parkinson's disease.
mesh_terms: D000368:Aged; D001923:Brain Chemistry; D004298:Dopamine / Q000032:analysis; D004723:Endorphins / Q000032:analysis*; D004745:Enkephalins / Q000032:analysis*; D006801:Humans; D008715:Methionine / Q000032:analysis*; D010300:Parkinson Disease / Q000378:metabolism*
chemical_list: D004723:Endorphins; D004745:Enkephalins; D008715:Methionine; D004298:Dopamine