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Shelton AO, Mangel M.Shelton AO, et al. Among authors: mangel m.Proc Natl Acad Sci U S A. 2011 Apr 26;108(17):7075-80. doi: 10.1073/pnas.1100334108. Epub 2011 Apr 11.Proc Natl Acad Sci U S A. 2011.PMID: 21482785Free PMC article.