title: Interaction of methadone and pentobarbital on chained fixed-interval performance in pigeons.
mesh_terms: D000818:Animals; D010856:Columbidae; D003216:Conditioning, Operant / Q000187:drug effects*; D004347:Drug Interactions; D008297:Male; D008691:Methadone / Q000494:pharmacology*; D010424:Pentobarbital / Q000494:pharmacology*; D012055:Reinforcement Schedule
chemical_list: D010424:Pentobarbital; D008691:Methadone