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Reinhardt K, Naylor RA, Siva-Jothy MT.Reinhardt K, et al.Proc Natl Acad Sci U S A. 2009 Dec 22;106(51):21743-7. doi: 10.1073/pnas.0905347106. Epub 2009 Dec 8.Proc Natl Acad Sci U S A. 2009.PMID: 19996174Free PMC article.