Funding for this research was provided by:
National Natural Science Foundation of China (81470737, 81400496)
Text and Data Mining valid from 2018-12-01
Received: 15 May 2018
Accepted: 18 December 2018
First Online: 29 December 2018
Ethics approval and consent to participate
: The mothers participated in the study voluntarily and all signed written informed consent. For infants, parental written informed consent was also obtained. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of the Ninth People’s Hospital, Shanghai Jiao Tong University prior to the implementation of the study (Project identification code: 201410).
: Not applicable.
: The authors declare that they have no competing interests.
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