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Barbour JD, Ndhlovu LC, Xuan Tan Q, Ho T, Epling L, Bredt BM, Levy JA, Hecht FM, Sinclair E.Barbour JD, et al.PLoS One. 2009;4(2):e4408. doi: 10.1371/journal.pone.0004408. Epub 2009 Feb 9.PLoS One. 2009.PMID: 19198651Free PMC article.