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López-Giraldo A, Rodríguez-Roisin R, Agustí A.López-Giraldo A, et al.Med Clin (Barc). 2015 Jun 8;144(11):507-13. doi: 10.1016/j.medcli.2014.03.009. Epub 2014 May 10.Med Clin (Barc). 2015.PMID: 24820902Review.Spanish.