Funding for this research was provided by:
National Natural Science Foundation of China (30830106, 81571091)
National Youth Foundation of China (81100454)
Received: 27 December 2017
Accepted: 5 March 2018
First Online: 13 March 2018
: All animal experiments were approved by the Animal Experimentation Ethical Committee of the Zoology Center at Chongqing Medical University (Chongqing, China) [SCXK (Yu) 2012-0015].
: Not applicable.
: The authors declare that they have no competing interests.
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