Funding for this research was provided by:
the Key Program of Hebei Natural Science Foundation (No. H2017206391)
the Project of Clinical Medical Talent Training and Basic Project Research Funded by Government (Hebei finance society (2017) No. 46)
Text and Data Mining valid from 2019-01-26
Received: 26 October 2018
Accepted: 21 January 2019
First Online: 26 January 2019
Ethics approval and consent to participate
: All procedures performed in this study were in accordance with the ethical standards of the institutional research committee and with the 2008 Helsinki declaration. The study was approved by the Ethics Committee of Hebei Medical University and the Second Hospital of Hebei Medical University. Written informed consent was obtained from all study subjects.
: Not applicable.
: We declare that we have no competing interests.
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