Funding for this research was provided by:
National Natural Science Foundation of China (81302755, 81372576, 81673438)
State's Key Project of Research and Development Plan (YFC1305902)
Key projects of Anhui provincial natural science research in colleges and universities (KJ2017A167)
Received: 28 August 2018
Accepted: 3 February 2019
First Online: 13 February 2019
Ethics approval and consent to participate
: All efforts were performed to minimize the number of pregnant rats used and their suffering. The procedures were approved by the Animal Care and the Ethic Committee of Animal Usage of Anhui Medical University.
: Not applicable.
: The authors declare that they have no competing interests.
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