Li, Lin
Zhao, Wenzhuo
Wang, Mengmeng
Hu, Jie
Wang, Enxin
Zhao, Yan
Liu, Lei http://orcid.org/0000-0002-1479-0192
Funding for this research was provided by:
National Natural Science Foundation of China (81702999)
Health and Family Planning commission of Shaanxi province (2017SF-208)
Article History
Received: 9 September 2017
Accepted: 23 July 2018
First Online: 4 September 2018
Ethics approval and consent to participate
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: The authors declare that they have no competing interests.
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