activation


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ac·ti·va·tion

(ak'ti-vā'shŭn),
1. The act of rendering active.
2. An increase in the energy content of an atom or molecule, effected by means such as increased temperature or absorption of light photons that renders that atom or molecule more reactive.
3. Techniques of stimulating the brain by light, sound, electricity, or chemical agents, to elicit abnormal activity in the electroencephalogram.
4. Stimulation of peripheral nerve fibers to the point that action potentials are initiated.
5. Stimulation of cell division in an oocyte by fertilization or by artificial means.
6. The act of making radioactive.

See also: cross-section.

activation

/ac·ti·va·tion/ (ak″tĭ-va´shun)
1. the act or process of rendering active.
2. the transformation of a proenzyme into an active enzyme by the action of a kinase or another enzyme.
3. the process by which the central nervous system is stimulated into activity through the mediation of the reticular activating system.
4. the deliberate induction of a pattern of electrical activity in the brain.

allosteric activation  increase in enzyme activity by binding of an effector at an allosteric site that affects binding or turnover at the catalytic site.
contact activation  initiation of the intrinsic pathway of coagulation through interaction of coagulation factor XII with various electronegative surfaces.
lymphocyte activation  stimulation of lymphocytes by antigen or mitogens resulting in macromolecular synthesis (RNA, protein, and DNA) and production of lymphokines, followed by proliferation and differentiation of the progeny into various effector and memory cells.

activation

[ak′tivā′shən]
1 the promotion or production of an activity, such as the generation of a catalyst, protein synthesis, or enzymatic function.
2 the treatment of sewage using a combination of bacteria and air.

activation

The enabling of an eClinical trial system to capture data.

Activation

Biochemistry The conversion, often enzymatic, of a molecule to a functionally active form—e.g., activation of complement or coagulation cascades.
Haematology See Plasminogen activation
Immunology See Complement activation, Lymphocyte activation, Macrophage activation, T cell activation
Molecular biology See Dark reactivation, Ras activation, Transactivation
Neurology The stimulation of a nerve to a level high enough to kick over its action potential.
NIHspeak The decision by a group or institution to open an investigational new drug (IND) study. 
Nuclear medicine Radioactivation. The interaction of a particle with an atomic nucleus, which “kicks” the nucleus into an unstable, high energy state, causing it to become radioactive.

activation

Hematology See Plasminogen activation Immunology Lymphocyte activation, see there. See Complement activation, Macrophage activation Neurology The stimulation of a nerve to a level high enough to kick over its action potential.

ac·ti·va·tion

(ak'ti-vā'shŭn)
1. The act of rendering active.
2. An increase in the energy content of an atom or molecule, through the raising of temperature, absorption of photons, or other means.
3. Techniques of stimulating the brain by light, sound, electricity, or chemical agents, to elicit abnormal activity in the electroencephalogram.
4. Stimulation of peripheral nerve fibers to the point that action potentials are initiated.
5. Stimulation of cell division in an oocyte by fertilization or by artificial means.
6. The act of making radioactive.

activation

initiation of a response in an effector (i.e. a muscle or gland).

ac·ti·va·tion

(ak'ti-vā'shŭn)
1. Act of rendering active.
2. Act of making something radioactive.

activation

the process of activating.

activation analysis
a method of analyzing the content of elements in samples of biological material. The sample is bombarded with nuclear particles and the elements in it measured by the radiation emitted by their radioactive daughter products. Called also radioactivation analysis.
activation energy
the difference in energy between the ground state of the reactants in a reaction and the point of maximum energy or transition state of the reactions. Usually lowered by enzyme catalysts.
activation factor
activation unit
the combination of complement (C4, C2 and C3) that binds to the antigen-antibody complex in the initial reaction step in the classical pathway of complement activation. See also complement.

Patient discussion about activation

Q. Are there any nice activities for adults with autism? I've been helping a very nice man of 45 of years old and I'm looking for some new things I can do with him in our time together. any ideas?

A. Autistic people react wonderfully with animals. for instance- i saw a group of severe Autistic teenagers going to swim with dolphins. the effect was amazing! taking him to the zoo, or even to the park to feed ducks, pet dogs, whatever.. could have a great effect on him.
hope i helped!
tell me how it went.

Q. what is a passive smoking? and is it dangerous as an active?

A. Passive smoking is the exposure to cigarettes smoke emitted from cigarettes smoke by other person. It's dangerous and may increase the risk to several diseases similar to active smoking (one's exposure to smoke emitted from the cigarettes he or she is smoking) although the risk is of lower magnitude. Example for passive smoking is children of smokers etc.

You may read more here:http://www.nlm.nih.gov/medlineplus/secondhandsmoke.html

Q. i swim a lot ! what are the advantages of swimming over other sport activities? on what part of the body does it work the most ?

A. its a good workout but your not really going to burn as much calories as a regular work out.

More discussions about activation
References in periodicals archive ?
Insignia Health specializes in helping hospitals, health plans, pharmaceutical firms and other organizations assess and increase activation levels to improve health outcomes for the individuals they support.
The Safe Activation service automates activation and licensing of Trial, Product, Subscription and Floating licenses for digital products.
Based on the implementation of project activities will lead to the transfer of know-how, principles and practical experience especially with the concept of activation for elderly and demented people with disabilities, which is aimed at stimulating the senses, which in their active involvement to revitalize people, motivating and helping shape his life in age.
Kindle Fire tablets are beginning to make their way into the workplace with a steady stream of activations since Amazon launched the product late last year.
Similar to the whole UP, the soluble-fraction-induced activation of ERK1/2 and p38 was inhibited by losartan (Figure 5C,D).
Ease of forward migration, with Activation 5 designed to be upwardly compatible with current versions of both MetaSolv ASAP and MetaSolv IP Service Activator, enabling a smooth transition to the advanced functionality available in this new release.
Despite sky-high concentrations of the vires, sooty mangabeys show few signs of immune activation and don't lose their CD4 T cells as macaques do, he reported at the 9th Conference on Retroviruses and Opportunistic Infections held in Seattle in February.
This iCloud Activation Lock Remove and Bypass is compatible with all iOS devices like iOS 7, iOS 8 , iOS 8.
Manage a dual license activation for Try/Buy or Student/Teacher editions without additional programming.
Chronic activation damages the immune system further and propagates the infection.
This suggests that activation of the enzyme represents the initial manifestation of EMFS' biological influence, Uckun says.
Contrary to the cone rheometer, the TMA mode of the thermal analyzer allowed us to quantitatively measure sponge expansion during the cure and blow reactions and determine the blow/cure system gas activation temperature.

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