Funding for this research was provided by:
Affiliated Hospital of Zunyi Medical University (201808)
Zunyi Medical University (ZKDC2018017)
Department of Education of Guizhou Province (20195201909)
Received: 14 September 2019
Accepted: 9 October 2019
First Online: 29 October 2019
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Affiliated Hospital of Zunyi Medical University, the approval number was ZYFYLS2018(81). Before sample collection, a written informed consent was obtained from all the patients or their guardians, and patient/study subject privacy was carefully protected.
: Not applicable.
: The authors declare that they have no competing interests.