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<http://ichef-1.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2014/08/19/140819155245_cancer_colon_spl_304x171_spl.jpg>
<http://www.bbc.com/mundo/noticias/2014/08/140819_virus_regula_bacteria_intestinos_mes.shtml>