Funding for this research was provided by:
Natural Science Foundation of Shaanxi Province (2012JQ4001, 2016JQ8002)
National Natural Science Foundation of China (31300979)
Youth Training Project of PLA Medical Science and Technology, China (15QNP066)
Text and Data Mining valid from 2018-07-11
Received: 28 September 2017
Accepted: 3 July 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: Ethics approval of this study was obtained from committee of Xijing Hospital and all procedures performed involving human participants were in accordance with the ethical standards of this committee. Informed consent was obtained from all individual participants as verbal form included in the study. All individual participants agreed to choose verbal form instead of written form and this was approved by the committee of Xijing Hospital.
: Not applicable.
: The authors declared that they have no competing interests.
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