Funding for this research was provided by:
Key Research and Development Foundation of Shandong Province (2017GSF218034, 2016GSF201010)
Received: 1 May 2019
Accepted: 2 August 2019
First Online: 13 August 2019
Ethics approval and consent to participate
: Our study protocol was approved by the Ethics Committee of Qilu Hospital of Shandong University, and conducted in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1964 and later versions. Written informed consents were obtained from all patients in this study.
: Not applicable.
: The authors declare that they have no competing interests.