title: [Normal bacterial flora and its balancing effects, with some reference to germ-free animal].
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000254:growth & development; D005856:Germ-Free Life; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D051379:Mice; D051381:Rats