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Cras P, Kawai M, Lowery D, Gonzalez-DeWhitt P, Greenberg B, Perry G.Cras P, et al.Proc Natl Acad Sci U S A. 1991 Sep 1;88(17):7552-6. doi: 10.1073/pnas.88.17.7552.Proc Natl Acad Sci U S A. 1991.PMID: 1652752Free PMC article.