Funding for this research was provided by:
the National Natural Science Fund Project (81373676)
the National Natural Science Fund Project (81674018)
the Science and Technology Development Project of Shandong Province (2014GSF119021)
Received: 29 March 2019
Accepted: 4 June 2019
First Online: 11 June 2019
Ethics approval and consent to participate
: This study was approved by the Health Authorities and Ethics Committees of Shandong University of Traditional Chinese Medicine Affiliated Hospital. All participants signed an informed consent form prior to the study.
: Not applicable.
: The authors declare that they have no competing interests.