title: Cocaine and heroin use by methadone maintenance patients.
authors.affiliation: Addiction Research Center, Baltimore, MD 21224.
authors.forename: J C
authors.initials: JC
authors.lastname: Ball
authors.forename: A
authors.initials: A
authors.lastname: Ross
authors.forename: J H
authors.initials: JH
authors.lastname: Jaffe
mesh_terms: D003042:Cocaine; D005500:Follow-Up Studies; D006556:Heroin Dependence / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D015813:Substance Abuse Detection / Q000379:methods*; D019966:Substance-Related Disorders / Q000534:rehabilitation*
chemical_list: D003042:Cocaine; D008691:Methadone