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Li H, Zong XN, Ji CY, Mi J.Li H, et al.Zhonghua Liu Xing Bing Xue Za Zhi. 2010 Jun;31(6):616-20.Zhonghua Liu Xing Bing Xue Za Zhi. 2010.PMID: 21163089Chinese.
Zong XN, Li H.Zong XN, et al.Bull World Health Organ. 2014 Aug 1;92(8):555-64. doi: 10.2471/BLT.13.126243. Epub 2014 Jun 5.Bull World Health Organ. 2014.PMID: 25177070Free PMC article.