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Calderón-Garcidueñas AL, Pérez-Loria O, Alberto-Sagástegui J, Farías-García R.Calderón-Garcidueñas AL, et al.Gac Med Mex. 2000 May-Jun;136(3):267-71.Gac Med Mex. 2000.PMID: 10893855Review.Spanish.