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Wolpert EZ, Petersson M, Chambers BJ, Sandberg JK, Kiessling R, Ljunggren HG, Kärre K.Wolpert EZ, et al. Among authors: sandberg jk.Proc Natl Acad Sci U S A. 1997 Oct 14;94(21):11496-501. doi: 10.1073/pnas.94.21.11496.Proc Natl Acad Sci U S A. 1997.PMID: 9326638Free PMC article.