title: Maturation of a hypothesis.
authors.affiliation: Respiratory Sciences Center, The University of Arizona, Tucson 85724-5030, USA. fernando@resp-sci.arizona.edu
authors.forename: F D
authors.initials: FD
authors.lastname: Martinez
mesh_terms: D001419:Bacteria / Q000276:immunology*; D004781:Environmental Exposure; D006801:Humans; D006920:Hygiene; D006967:Hypersensitivity / Q000209:etiology* / Q000276:immunology* / Q000382:microbiology