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Hernández JL, Palacios-Araus L, Echevarría S, Herrán A, Campo JF, Riancho JA.Hernández JL, et al.Postgrad Med J. 1997 Dec;73(866):779-84. doi: 10.1136/pgmj.73.866.779.Postgrad Med J. 1997.PMID: 9497946Free PMC article.Review.