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Article History

Received: 27 July 2018

Accepted: 12 April 2019

First Online: 6 May 2019

Ethics approval and consent to participate

: This article does not contain any studies with animals performed by any of the authors. All procedures performed in studies involving human participants were in accordance with the ethical standards of the Ethics Committee of Shanghai First Maternity and Infant Hospital. The study protocol was approved by the Ethical Committee of the Tongji University School of Medicine. Infant Hospital and committee reference number is KS18109. Written informed consent was obtained from all participants.

: Not applicable.

: We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled.

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