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Ekstrand AJ, Cao R, Bjorndahl M, Nystrom S, Jonsson-Rylander AC, Hassani H, Hallberg B, Nordlander M, Cao Y.Ekstrand AJ, et al. Among authors: hassani h.Proc Natl Acad Sci U S A. 2003 May 13;100(10):6033-8. doi: 10.1073/pnas.1135965100. Epub 2003 May 2.Proc Natl Acad Sci U S A. 2003.PMID: 12730369Free PMC article.