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Wang SH, Redondo RL, Morris RG.Wang SH, et al.Proc Natl Acad Sci U S A. 2010 Nov 9;107(45):19537-42. doi: 10.1073/pnas.1008638107. Epub 2010 Oct 20.Proc Natl Acad Sci U S A. 2010.PMID: 20962282Free PMC article.