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Cui X, Wei T, Chowda-Reddy RV, Sun G, Wang A.Cui X, et al.Virology. 2010 Feb 5;397(1):56-63. doi: 10.1016/j.virol.2009.11.015. Epub 2009 Nov 30.Virology. 2010.PMID: 19945728Free article.