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Dabiri GA, Sanger JM, Portnoy DA, Southwick FS.Dabiri GA, et al. Among authors: portnoy da.Proc Natl Acad Sci U S A. 1990 Aug;87(16):6068-72. doi: 10.1073/pnas.87.16.6068.Proc Natl Acad Sci U S A. 1990.PMID: 2117270Free PMC article.