. . . . . . . "[Chronic heroin and cocaine abuse is associated with decreased serum concentrations of the nerve growth factor and brain-derived neurotrophic factor.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2017-01-25"^^ . . "Gene-disease associations manually curated."@en . "DisGeNET evidence - CURATED"@en . "2017-10-17T13:15:00+02:00"^^ . . . . . . . . . . . "v5.0.0.0" . "v5.0.0" .