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  1. Address correspondence and reprint requests to Bao-en Shan, MD, Research Center, Fourth Hospital of Hebei Medical University, 12 Jiankang Road, Shijiazhuang 050011, China. E-mail: baoenshan{at} or zzm701105{at}


Zhang Z, Xiao S, Sun G, et al

Publication history

  • Received September 22, 2013
  • Accepted December 19, 2013
  • First published March 1, 2014.
Online issue publication 
February 25, 2019

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