B. Edible allergens: such as milk, eggs, fish and shrimp, beef and mutton, seafood, animal fat, exogenous protein, alcohol, medicine, antibiotics, anti-inflammatory drugs, sesame oil, essence, onion, ginger, garlic and some fruits and vegetables. ?
C contact allergens: such as cold air, hot air, ultraviolet rays, radiation, cosmetics, shampoo, detergent, hair dye, soap, chemical fiber products, plastics, metal ornaments (watches, necklaces, rings, earrings), bacteria, molds, viruses, parasites, etc. ?
A specific immune response that occurs after the body is stimulated by the same antigen again, showing tissue damage or physiological dysfunction. It can also be said that allergic reaction is an abnormal, harmful and pathological immune reaction.
Extended data:
When the body is exposed to allergens for the first time, it takes a incubation period (1 ~ 2 weeks) for immunocompetent cells to produce corresponding antibodies or sensitized lymphocytes. During this period, the body has no abnormal reaction, but it has the potential to have allergic reactions.
In the allergic reaction stage, when the sensitized organism is exposed to the same allergen again, the allergen combines with the corresponding antibody or sensitized lymphocyte, causing physiological dysfunction or tissue damage of the organism, that is, abnormal immune response, which occurs rapidly, ranging from a few seconds to dozens of seconds to more than 2-3 days.
One of the reasons of allergic reaction is the individual's immune function; The nature, purity and route of antigen entering the body. The main factor of these two factors is the former, that is, the difference of individual immune response.
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