Xu, Renguo
Liu, Zhen
Hou, Jiande
Huang, Tao
Yang, Ming
Article History
Received: 21 February 2018
Accepted: 20 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: This study was approved by YeDa Hospital.
: Not applicable. The manuscript does not contain data from any individual person.
: The authors declare that they have no competing interests.
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