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Lipman RS, Hou YM.Lipman RS, et al. Among authors: hou ym.Proc Natl Acad Sci U S A. 1998 Nov 10;95(23):13495-500. doi: 10.1073/pnas.95.23.13495.Proc Natl Acad Sci U S A. 1998.PMID: 9811828Free PMC article.