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Perkins ND, Schmid RM, Duckett CS, Leung K, Rice NR, Nabel GJ.Perkins ND, et al.Proc Natl Acad Sci U S A. 1992 Mar 1;89(5):1529-33. doi: 10.1073/pnas.89.5.1529.Proc Natl Acad Sci U S A. 1992.PMID: 1542644Free PMC article.