Funding for this research was provided by:
Health and Family Planning Commission of Jiangsu Province Youth Research Subject (Q201606)
the Suzhou Applied Basic Research (Sys201535)
Jiangsu province commission of health and family planning research funding (H2017064)
Suzhou science and technology development plan (SS201864)
Received: 2 April 2018
Accepted: 13 March 2019
First Online: 19 March 2019
Ethics approval and consent to participate
: The study was approved by the ethical committee of The First Affiliated Hospital of Soochow University, China. Written informed consent was obtained from all study participants.
: Not applicable.
: The authors declare that they have no competing interests.
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