Funding for this research was provided by:
the foundation of Science & Technology Department of Sichuan Province (0040205301C35)
Received: 22 October 2017
Accepted: 30 January 2018
First Online: 7 February 2018
: This study was approved by the Institutional Animal Care and Use Committee at the West China Center of Medical Sciences, Sichuan University, Chengdu, Sichuan, China.
: Not applicable.
: The authors declare that they have no competing interests.
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