Funding for this research was provided by:
National Natural Science Foundation of China (81871214)
National Key R&D Program of China (2017YFC1001603)
Text and Data Mining valid from 2019-03-09
Received: 26 September 2018
Accepted: 24 January 2019
First Online: 9 March 2019
Compliance with ethical standards
: The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.
: This study was approved by the Institutional Reviewer Board of Sixth Affiliated Hospital of Sun Yat-sen University.
: For this type of study formal consent is not required. This article does not contain any studies with human participants or animals performed by any of the authors.
: Because of the retrospective nature of the study the requirement of informed patient consent was waived.