Jia, Wen
Lei, Xiaoping
Dong, Wenbin
Li, Qingping
Article History
Received: 9 February 2017
Accepted: 28 January 2018
First Online: 12 February 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of The Hospital Affiliated of Southwest Medical University. Written informed consent was obtained from the legal guardians.
: Not applicable.
: The authors declare that they have no competing interests.
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