Funding for this research was provided by:
National Natural Science Foundation of China (81702212)
Text and Data Mining valid from 2018-09-20
Received: 2 August 2018
Accepted: 10 September 2018
First Online: 20 September 2018
Ethics approval and consent to participate
: This retrospective study was approved and consented to participate by the Ethics Committee of The Second Hospital of Shanxi Medical University.
: All patients involved had given informed consent.
: The authors declare that they have no competing interests.
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