Article History
Received: 9 December 2018
Accepted: 3 June 2019
First Online: 12 June 2019
Compliance with ethical standards
:
: We have declared that no competing interests exist. The authors alone are responsible for the content and writing of the paper.
: The study complies with the Declaration of Helsinki and was approved by the Ethics Committee of Affiliated Hospital of Nantong University, and all patients gave written informed consent.