Du, P. http://orcid.org/0000-0001-8478-054X
Wang, S.-Y. http://orcid.org/0000-0002-5969-4348
Zheng, P.-F. http://orcid.org/0000-0002-8785-6391
Mao, J. http://orcid.org/0000-0003-4641-4674
Hu, H. http://orcid.org/0000-0003-3680-1582
Cheng, Z.-B. http://orcid.org/0000-0002-6468-0506
Article History
Received: 28 February 2019
Accepted: 18 March 2019
First Online: 20 April 2019
Compliances with ethical standards
:
: The authors declare that they have no conflict of interest concerning this article.
: The study was approved by the Ethics Committee of the Second Hospital of Lanzhou University, and the data were anonymously obtained and retrospectively analyzed. The clinical data of all patients were collected from the electronic medical records of the Second Hospital of Lanzhou University. This study was performed in accordance with the relevant guidelines and regulations, and conformed to the Declaration of Helsinki.
: Informed consents from participants were also waived due to the complete anonymity of the patients.