. . . . . . . . . . . . "[Human immunodeficiency virus type 1 (HIV-1) infection is established by virus variants that use the CCR5 co-receptor for entry (CCR5-tropic or R5 variants), whereas viruses that use CXCR4 as co-receptor (CXCR4-tropic or X4 variants) emerge during disease progression in approximately 50 % of infected subjects.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2016-02-19"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2016-05-13T12:45:51+02:00"^^ . . . . . . . . . . . "v4.0.0.0" . "v4.0.0" .