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Gürtler RE, Kitron U, Cecere MC, Segura EL, Cohen JE.Gürtler RE, et al.Proc Natl Acad Sci U S A. 2007 Oct 9;104(41):16194-9. doi: 10.1073/pnas.0700863104. Epub 2007 Oct 3.Proc Natl Acad Sci U S A. 2007.PMID: 17913895Free PMC article.