Li, Zhikun
Wang, Yi
Xu, Youjia
Xu, Wei
Zhu, Xiaodong
Chen, Chao
Funding for this research was provided by:
National Natural Science Foundation of China (81903039)
The Sponsored by Shanghai Sailing Program (19YF1444500)
Changning district health and family planning commission (20164Y003)
Changning district committee of science and technology (CNKW2017Y07)
The Sixth people's hospital of Shanghai medical group projects (ly201802)
Article History
Received: 21 January 2020
Accepted: 5 February 2020
First Online: 17 February 2020
Ethics approval and consent to participate
: This retrospective study was approved and consented to participate by the Ethics Committee.
: Not applicable.
: The authors declare that they have no competing interests.