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Cohen SG, Schultz RM.Cohen SG, et al.Proc Natl Acad Sci U S A. 1967 Feb;57(2):243-9. doi: 10.1073/pnas.57.2.243.Proc Natl Acad Sci U S A. 1967.PMID: 16591460Free PMC article.No abstract available.
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