title: Effects of cocaine and morphine on concurrent schedule-controlled performances.
mesh_terms: D000818:Animals; D003042:Cocaine / Q000494:pharmacology*; D010856:Columbidae; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005502:Food; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D011930:Reaction Time; D013997:Time Factors
chemical_list: D009020:Morphine; D003042:Cocaine