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Kim SH, Markham JA, Weiler IJ, Greenough WT.Kim SH, et al. Among authors: markham ja.Proc Natl Acad Sci U S A. 2008 Mar 18;105(11):4429-34. doi: 10.1073/pnas.0800257105. Epub 2008 Mar 10.Proc Natl Acad Sci U S A. 2008.PMID: 18332424Free PMC article.