Funding for this research was provided by:
Hunan Science and Technology Department (2014TT2022)
Received: 13 August 2017
Accepted: 21 February 2018
First Online: 28 February 2018
Ethics approval and consent to participate
: The whole study was approved by the local research ethics committee of Xiangya Hospital Affiliated to Central South University (Changsha, Hunan Province, China).
: The authors declare that they have no competing interests.
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