Wang, Nianshi
Xu, Jing
Ma, Meiyan
Shan, Linghan
Jiao, Mingli
Xia, Qi
Tian, Wanxin
Zhang, Xiyu
Liu, Limin
Hao, Yanhua
Gao, Lijun
Wu, Qunhong
Funding for this research was provided by:
National Natural Science Foundation of China (71874045)
National Natural Science Foundation of China (71403073)
National Natural Science Foundation of China (71333003)
National Natural Science Foundation of China (71804036)
China Postdoctoral Science Foundation (2016M590296)
Heilongjiang Health and Family Planning Commission Project (2014-427)
Article History
Received: 6 March 2020
Accepted: 13 July 2020
First Online: 14 September 2020
Ethics approval and consent to participate
: Ethics approval and consent to participate is not applicable due to the retrospective nature of this study.
: All authors agree to publish.
: The authors declare that they have no competing interests.