Funding for this research was provided by:
China Scholarship Council (201808080126, 201706920036)
Key Technology Research and Development Program of Shandong (2016GSF201214)
Text and Data Mining valid from 2020-01-02
Received: 17 July 2019
Accepted: 13 December 2019
First Online: 2 January 2020
Compliance with ethical standards
: The authors declared that they have no potential conflicts of interests to declare.
: This review did not involve primary data collection from patients and as such research approval was not obtained.