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Link TM, Valentin-Hansen P, Brennan RG.Link TM, et al. Among authors: valentin hansen p.Proc Natl Acad Sci U S A. 2009 Nov 17;106(46):19292-7. doi: 10.1073/pnas.0908744106. Epub 2009 Nov 4.Proc Natl Acad Sci U S A. 2009.PMID: 19889981Free PMC article.