Funding for this research was provided by:
Natural Science Foundation of Guangxi Province (2016JJA140697)
Received: 12 August 2019
Accepted: 28 October 2019
First Online: 12 November 2019
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of The People’s Hospital of Guangxi Zhuang Autonomous Region. Informed consent was obtained from all the study subjects before enrollment.
: Not applicable.
: The authors declare that they have no competing interests.