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Carlson TA, Alvarez GA, Cavanagh P.Carlson TA, et al. Among authors: cavanagh p.Proc Natl Acad Sci U S A. 2007 Aug 14;104(33):13496-500. doi: 10.1073/pnas.0702685104. Epub 2007 Aug 2.Proc Natl Acad Sci U S A. 2007.PMID: 17673552Free PMC article.