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Chang YC, Penoyer LA, Kwon-Chung KJ.Chang YC, et al.Proc Natl Acad Sci U S A. 2001 Mar 13;98(6):3258-63. doi: 10.1073/pnas.061031998. Epub 2001 Feb 27.Proc Natl Acad Sci U S A. 2001.PMID: 11248066Free PMC article.