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Chen B, Schaevitz LR, McConnell SK.Chen B, et al.Proc Natl Acad Sci U S A. 2005 Nov 22;102(47):17184-9. doi: 10.1073/pnas.0508732102. Epub 2005 Nov 11.Proc Natl Acad Sci U S A. 2005.PMID: 16284245Free PMC article.