Received: 24 June 2018
Accepted: 14 February 2019
First Online: 22 February 2019
Ethics approval and consent to participate
: BOT tissues and OC specimens were obtained from Shanghai First Maternity and Infant Hospital, Tongji University (Shanghai, China) approved by the Ethics Committee of Shanghai First Maternity and Infant Hospital. Written informed consent was obtained from all study participants or their guardians.
: Not applicable
: The authors declare that they have no competing interests.
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