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Rivas-Santiago B, Sada E, Hernández-Pando R, Tsutsumi V.Rivas-Santiago B, et al.Salud Publica Mex. 2006 Jan-Feb;48(1):62-71. doi: 10.1590/s0036-36342006000100010.Salud Publica Mex. 2006.PMID: 16555536Review.Spanish.