Text and Data Mining valid from 2019-11-15
Received: 30 July 2019
Accepted: 9 November 2019
First Online: 15 November 2019
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.
: All the SPF animals were obtained from the Model Animal Research Center of Nanjing University (Nanjing, China). The operations conducted in this experiment were approved by the National Animal Ethics Committee under the guidance of the protocols.