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Evans MJ, Rice CM, Goff SP.Evans MJ, et al.Proc Natl Acad Sci U S A. 2004 Aug 31;101(35):13038-43. doi: 10.1073/pnas.0405152101. Epub 2004 Aug 23.Proc Natl Acad Sci U S A. 2004.PMID: 15326295Free PMC article.