reaction

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reaction

 [re-ak´shun]
1. opposite action or counteraction; the response of a part to stimulation.
2. the phenomena caused by the action of chemical agents; a chemical process in which one substance is transformed into another substance or substances.
3. in psychology, the mental or emotional state that develops in any particular situation.
4. the specific cellular effect produced by foreign matter, as in testing for allergies. For specific reactions, see under the name, such as pirquet's reaction.
reaction of degeneration the reaction to electrical stimulation of muscles whose nerves have degenerated, consisting of loss of response to a faradic stimulation in a muscle, and to galvanic and faradic stimulation in the nerve.
reaction time the time elapsing between the application of a stimulus and the resulting reaction.

re·ac·tion

(rē-ak'shŭn),
1. The response of a muscle or other living tissue or organism to a stimulus.
2. The color change effected in litmus and certain other organic pigments by contact with substances such as acids or alkalies; also the property that such substances possess to produce this change.
3. In chemistry, the intermolecular action of two or more substances on each other, whereby these substances are caused to disappear, with new ones being formed in their place (chemical reaction).
4. In immunology, in vivo or in vitro action of an antibody on a specific antigen, with or without the involvement of a complement or other components of the immune system.
[L. re-, again, backward, + actio, action]

reaction

Vox populi A response in a chemical, immunologic, physiologic, psychological, or other interaction. See Allergic reaction, Anaphylactic reaction, Anniversary reaction, Anxiety reaction, Conversion reaction, Cortical reaction, Cross- reaction, Downgrading reaction, Fixed drug reaction, Harlequin skin reaction, Hemagglutination inhibition reaction, Hemolytic transfusion reaction, Hysterical reaction, Late phase reaction, Leukemoid reaction, Leukoerythroblastic reaction, Leukotriene reaction, Magnet reaction, Mourning reaction, Myasthenic reaction, Nonhemolytic transfusion reaction, Parachute reaction, Pseudomyotonic reaction, Uphill reaction, Vasopermeability reaction, Wheal-and-flare reaction.

re·ac·tion

(rē-ak'shŭn)
1. The response of a muscle or other living tissue or organism to a stimulus.
2. The color change effected in litmus and certain other organic pigments by contact with substances such as acids or alkali; also the property that such substances possess to produce this change.
3. chemistry The intermolecular action of two or more substances on each other, whereby these substances are made to disappear and new ones are formed in their place (chemical reaction).
4. immunology Action of an antibody on a specific antigen in vivo or in vitro, with or without the involvement of complement or other components of the immunologic system.
[L. re-, again, backward, + actio, action]

reaction

a chemical process during which one substance is changed to another.

re·ac·tion

(rē-ak'shŭn)
1. Response of a muscle or other living tissue or organism to a stimulus.
2. Color change effected in litmus and other organic pigments by contact with substances.
[L. re-, again, backward, + actio, action]

Patient discussion about reaction

Q. what cause an allergic reaction?

A. Frankly? no ones actually knows for sure. What we do know, is that due to some reason the immune system of certain people, regard several non-harmful substances (e.g. peanuts, antibiotics, bee's venom) as an enemy and learn to react to it.

This tendency to develop abnormal responses to substances other people don't response to is called "atopy". It has a very strong genetic basis (i.e. it runs in families), and also depends on other factors such as the exposure to infections and the pattern of exposure to the allergen (the substance that causes allergy).

It's a very wide subject, far beyond the scope of my answer, so you may read more here:
http://www.nlm.nih.gov/medlineplus/allergy.html

Q. Is it common to get an allergic reaction in the eye from olive harvest? I've been around olive trees for a few hours and now feel like I have something in my eye but there is nothing there. can it be an allergic reaction? I dont get it from eating olives...

A. but in one eye..? that just doesn't seem likely. but i guess there is no reason not to try both treatments....

Q. I am worried about the allergic reactions I had from the Chinese herbal drug. I am worried about the allergic reactions I had from the Chinese herbal drug that I took for my arthritis…..are these safe?

A. Many people have some type of reaction to either a drug and even a supplement. You can check with your doc to get tested to see what your sensitivities are. Regarding arthritis, no milk, cheese, yogurt, butter, anything with milk for starters, AVOID like the plague! Suagr consumption too will raise hell with it. There is a product that someone I knew took, called, "Cell Guard" which he bought at a health food store or Whole Foods. After a couple of months, he was pain free. Its worth a try! Cell Guard is made with SOD or "superoxide dismutase"
Studies have shown that SOD can play a critical role in reducing internal inflammation and lessening pain associated with conditions such as arthritis! Check it out! Let me know how you do!

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