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Dowdy DW, Chaisson RE, Maartens G, Corbett EL, Dorman SE.Dowdy DW, et al.Proc Natl Acad Sci U S A. 2008 Aug 12;105(32):11293-8. doi: 10.1073/pnas.0800965105. Epub 2008 Aug 11.Proc Natl Acad Sci U S A. 2008.PMID: 18695217Free PMC article.