Table 1.

The H. pylori infection results in different Mongolian gerbil groups.

Name of group	Capital Medical University conventional animal	Capital Medical University clean animal	Dalian Medical University conventional animal	Zhejiang Provincial Experimental Animal Center conventional animal	Zhejiang Provincial Experimental Animal Center clean animal
Number of positive samples from gastric fluid nested PCR	1	0	0	1	0
Number of positive samples from gastric tissue nested PCR	2	0	0	1	0
Total number	35	23	20	31	26
Infection rate	9%	0%	0%	6%	0%