Funding for this research was provided by:
National Natural Science Foundation of China (81402364)
National Basic Research Program of China (973 Program) (2016YFC1302900)
Text and Data Mining valid from 2019-01-30
Received: 22 June 2018
Accepted: 21 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: This study was approved by the Human Research Ethical Committee of the Women’s Hospital, Zhejiang University, School of Medicine, China with protocol No. 20110014. Written informed consent was obtained from study participants according to institutional guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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