Funding for this research was provided by:
Natural Science Foundation of Shanghai (17411972800, 16ZR1419500, 15ZR1444100)
Text and Data Mining valid from 2019-01-18
Received: 27 June 2018
Accepted: 3 January 2019
First Online: 18 January 2019
Ethics approval and consent to participate
: The study was approved by the ethical review committee of the International Peace Maternity and Child Health Hospital (IPMCH).
: Consent was obtained from the patients for the publication of this report.
: The author declares that they have no competing interests.
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