title: Letter: Hydroxyamphetamine test in Horner's syndrome.
mesh_terms: D000661:Amphetamine / Q000032:analysis; D000662:Amphetamines; D004837:Epinephrine / Q000378:metabolism; D006732:Horner Syndrome / Q000175:diagnosis*; D006801:Humans; D007498:Iris / Q000187:drug effects / Q000294:innervation; D009130:Muscle, Smooth / Q000187:drug effects; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism; D009638:Norepinephrine / Q000032:analysis; D013268:Stimulation, Chemical
chemical_list: D000662:Amphetamines; D000661:Amphetamine; D009638:Norepinephrine; D004837:Epinephrine