Article History
Received: 15 November 2017
Accepted: 20 April 2018
First Online: 27 April 2018
Ethics approval
: This experiment was approved by the Ethics Committee of the Second Military Medical University, China, and was conducted according with international guidelines for animal experiments. The animals were utilized and managed according to the guidelines of the National Institutes of Health (NIH Publication No. 85-23, revised 1996).
: The authors declare that they have no competing interests.
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