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Gu SH, Wang SY, Zhang XY, Ji P, Liu JT, Wang GR, Wu KM, Guo YY, Zhou JJ, Zhang YJ.Gu SH, et al. Among authors: guo yy.PLoS One. 2012;7(8):e42871. doi: 10.1371/journal.pone.0042871. Epub 2012 Aug 10.PLoS One. 2012.PMID: 22900060Free PMC article.