Funding for this research was provided by:
the National Natural Science Foundation of China (30801075)
Article History
Received: 24 July 2017
Accepted: 25 April 2018
First Online: 10 May 2018
Ethics approval and consent to participate
: All animal protocols were approved by the Peking University Health Center Ethics Committee on Animal Care (LA2009–019, Beijing, P.R.China).
: The authors declare that they have no competing interests.
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