Funding for this research was provided by:
The Natural Science Foundation of Zhejiang Province (LY15H160063)
Received: 2 May 2019
Accepted: 13 September 2019
First Online: 26 October 2019
Ethics approval and consent to participate
: All the procedures followed were in accordance with the ethical guidelines of the Helsinki Declaration. The study protocol was approved by the Medical Ethical Committee of the First Affiliated Hospital of Wenzhou Medical University. Because all the patients in this retrospective study had died, informed consent was obtained from their family members or their pretreatment authorized recipients.
: Not applicable.
: The authors declare that they have no competing interests.