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Pelligrino DA, Vetri F, Xu HL.Pelligrino DA, et al.Semin Cell Dev Biol. 2011 Apr;22(2):229-36. doi: 10.1016/j.semcdb.2011.02.010. Epub 2011 Feb 15.Semin Cell Dev Biol. 2011.PMID: 21329762Free PMC article.Review.