The theory that infectious agents, symbiotic microorganisms, and parasites are normal stimulants for the maturation of the immune system toward a balanced immune response. The theory predicts that lack of such stimulation leads to allergies and AUTOIMMUNE DISEASES.
The science dealing with the establishment and maintenance of health in the individual and the group. It includes the conditions and practices conducive to health. (Webster, 3d ed)
Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.
Commonly known as parasitic worms, this group includes the ACANTHOCEPHALA; NEMATODA; and PLATYHELMINTHS. Some authors consider certain species of LEECHES that can become temporarily parasitic as helminths.
Infestation with parasitic worms of the helminth class.
Invasion of the host organism by microorganisms that can cause pathological conditions or diseases.
A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).
Antigen-type substances that produce immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE).
The practice of personal hygiene of the mouth. It includes the maintenance of oral cleanliness, tissue tone, and general preservation of oral health.
Practices involved in preventing the transmission of diseases by hand.
A combination of the debris index and the dental calculus index to determine the status of oral hygiene.
A chlorinated hydrocarbon used as an industrial solvent and cooling liquid in electrical transformers. It is a potential carcinogen.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)