Funding for this research was provided by:
Hebei Natural Science Foundation (H2018206066)
Article History
Received: 29 October 2018
Accepted: 17 June 2019
First Online: 24 June 2019
Ethics approval and consent to participate
: The Ethics Committee of Second Hospital of Hebei Medical University approved this prospective study. Written informed consent was obtained from all individual participants included in the study. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Not applicable.
: The authors declare that they have no competing interests.