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  1. Address correspondence and reprint requests to Zhu Yang, Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Chongqing Medical University, 76# Linjiang Rd, Yuzhong District, Chongqing 400010, People’s Republic of China. E-mail: yangzhu_cqmu{at}


Liang X, Liu Y, Zeng L, et al

Publication history

  • Received March 13, 2014
  • Accepted May 1, 2014
  • First published September 1, 2014.
Online issue publication 
September 01, 2014

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