Li, Zhen
Xu, Zhike
Wang, Yaqin
Liu, Qiang
Chen, Bin
Funding for this research was provided by:
Sichuan provincial health and family planning commission (150065)
Article History
Received: 20 April 2018
Accepted: 9 October 2018
First Online: 6 November 2018
Ethics approval and consent to participate
: The study was approved by the ethics committee of Leshan people’s hospital and adhered to the Declaration of Helsinki. Written informed consents were obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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