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Mendez-Otero R, de Freitas GR, André C, de Mendonça ML, Friedrich M, Oliveira-Filho J.Mendez-Otero R, et al.Regen Med. 2007 Jul;2(4):417-23. doi: 10.2217/17460751.2.4.417.Regen Med. 2007.PMID: 17635049Review.