Funding for this research was provided by:
National Key R&D Program of China (SQ2017YFSF080001)
National Natural Science Foundation of China (81501236)
Text and Data Mining valid from 2018-05-29
Received: 12 February 2018
Accepted: 20 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: Obstetrics and Gynecology Peking Union Medical College Hospital Human Research Ethics Committee Approval was obtained for the use of all samples.
: The authors declare that they have no competing interests.
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