Funding for this research was provided by:
2015 Social Development Science and Technology Support Fund (KH1601190)
Text and Data Mining valid from 2018-08-07
Received: 21 November 2017
Accepted: 2 August 2018
First Online: 7 August 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Hunan Province People’s Hospital.
: Not applicable.
: The authors declared that they have no competing interests.
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