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Wallis RS, Amir-Tahmasseb M, Ellner JJ.Wallis RS, et al.Proc Natl Acad Sci U S A. 1990 May;87(9):3348-52. doi: 10.1073/pnas.87.9.3348.Proc Natl Acad Sci U S A. 1990.PMID: 2110362Free PMC article.