Funding for this research was provided by:
National Health and Family Planning Commission of the People's Republic of China (Grant No. KF201704)
Natural Science Foundation of Shandong Province (Grant No. ZR2017LH012)
National Natural Science Foundation of China (Grant No. 81871200)
Natural Science Foundation of Fujian Province (Grant No. 2017D018)
Received: 21 February 2019
Accepted: 23 July 2019
First Online: 1 August 2019
Ethics approval and consent to participate
: This study was approved by the Medical Ethics Committee of Affiliated Yantai Yuhuangding Hospital of Qingdao University. Written informed consent to participate was obtained from all patients for being included in the study on behalf of the patients.
: Not application.
: The authors declare that they have no competing interests.