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Sipsas NV, Kalams SA, Trocha A, He S, Blattner WA, Walker BD, Johnson RP.Sipsas NV, et al. Among authors: walker bd.J Clin Invest. 1997 Feb 15;99(4):752-62. doi: 10.1172/JCI119221.J Clin Invest. 1997.PMID: 9045880Free PMC article.