Funding for this research was provided by:
National Natural Science Foundation of China (81560107, 81160062)
Science and Technology Application Project of Yunnan Province (2014FB091)
Received: 18 January 2018
Accepted: 26 June 2018
First Online: 2 August 2018
Ethics approval and consent to participate
: This study was approved by the Medical Ethics Committee of the First People’s Hospital of Yunnan Province.
: Not applicable
: The authors declare that they have no competing interests.
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