Physiological relevance

Stimulation of the neuron lea ding to electrical activation of the nerve terminal in a physiologically relevant manner should eUcit a calcium-dependent release of the neurotransmitter. Although release is dependent on extracellular calcium, intracellular calcium homeostasis may also modulate the process. Neurotransmitter release that is independent of extracellular calcium is usually artifactual, or in some cases may represent release from a non-neuronal sources such as gha (3). 

It is worth considering hypothesis testing in general from the standpoint of the choice of models one has available to fit data. On the surface, it is clear that the more complex a model is (more fitting parameters) the greater the verisimilitude of the data to the calculated line (i.e., the smaller will be the differences between the real and predicted values). Therefore, the more complex the model the more likely it will accurately fit the data. However, there are other factors that must be considered. One is the physiological relevance... 

Factor Xlla is a serine protease that activates FXI to FXIa (Fig. 5). This system is not of physiologic relevance since patients with hereditary deficiencies of factor XII, prekallikrein, and high-molecular weight kininogen do not present with bleeding symptoms. 

Crucial data regarding the physiological relevance of MDR transporters came from knockout mice studies. Surprisingly, loss of these genes does not result in an obvious phenotype MDR knockout mice are viable and... 

Cyano- and hydroxocobalamin - both can be converted to the physiologically relevant coenzymes methyl- and 5 -deoxyadenosylcobalamin in the liver -are used for therapeutical applications. When pernicious anemia caused by chronic atrophic gastritis has been diagnosed, it is treated as follows During the first 7 days of treatment, 1000 pg of hydroxocobalamin/d are administered parenterally, usually intramuscularly. Then, the same dose is given once weekly for 4-6 weeks. The aim is to alleviate the deficiency symptoms and at the same time to replenish the stores. Afterwards, 1000 pg hydroxocobalamin should be given parenterally every 2 months lifelong to avoid relapse [1, 2]. 

This polypeptide is structurally identical to ABA-type triblock copolymer with a central hydrophdic elastomeric end-block capped with two hydrophobic plastic end-blocks and exhibits amphiphilic characteristics. The end-blocks of the polymer were chosen in such a way that their LCST would reside at or near room temperature. Thus the polymer exhibits phase separation, which is analogue to conventional TPEs, and offers TPE gels under physiological relevant conditions [104]. Glutamic acid residue is placed periodically in the elastomeric mid-block to increase its affinity towards the aqueous... 

Another point is the concentration of the antioxidant which, in order to have physiological relevance, should be in the physiological range, i.e., not above 1 to 5 aM. Finally, when evaluating antioxidant capacities of foods and food extracts, one should take into account the presence of all the possible antioxidant molecules (phenols, vitamin E, etc.) to explain the results because interactions can occur between antioxidant molecules. 

The physiologically relevant function of the E-IIs is vectorial phosphorylation, i.e., transport with concomitant phosphorylation of the sugar. This reaction requires a phosphoryl group donor, for instance, P-HPr, and it may even be argued that the active species is phosphorylated E-II,... 

A number of the techniques that have been employed have the ability to directly monitor free-radical species either in vitro or in vivo [predominantly those involving electron spin resonance (e.s.r.) spectroscopy]. However, since many physiologically relevant free radicals have extremely short half-lives (e.g. 10 s for OH), the majority of the methods utilized detect products arising from their reactions with chemical components present (i.e. indirect methods). These indirect methods for... 

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