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Rost B, Sander C.Rost B, et al.Proc Natl Acad Sci U S A. 1993 Aug 15;90(16):7558-62. doi: 10.1073/pnas.90.16.7558.Proc Natl Acad Sci U S A. 1993.PMID: 8356056Free PMC article.