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Grimaldo M, Borja-Aburto VH, Ramírez AL, Ponce M, Rosas M, Díaz-Barriga F.Grimaldo M, et al.Environ Res. 1995 Jan;68(1):25-30. doi: 10.1006/enrs.1995.1004.Environ Res. 1995.PMID: 7729383