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Li N, Carrel L.Li N, et al. Among authors: carrel l.Proc Natl Acad Sci U S A. 2008 Nov 4;105(44):17055-60. doi: 10.1073/pnas.0807765105. Epub 2008 Oct 29.Proc Natl Acad Sci U S A. 2008.PMID: 18971342Free PMC article.