Dynamics of the content of common mature T-lymphocytes in the rat’s blood on the 14th day of the research in conditions of experimental bacterial-immune periodontitis development and treatment by quercetin (% of control). Notes: * – significant of differences in relation to the intact animals (p<0.01); # – significant of differences in relation to the animals with periodontitis on the 14th day of the experiment without treatment (p<0.01).