Selectivity ability

The ideal chelator should be inexpensive, capable of being administered orally and free of side effects. It should have a selective ability to bind Fe111 rapidly, relative to ferritin and transferrin,... 

Class IV drugs have a selective ability to block calcium entry into myocardial and vascular smooth-muscle cells. These drugs inhibit calcium influx by binding to specific channels in the cell membrane.12,15 As discussed previously, calcium entry plays an important role in the generation of the cardiac action potential, especially during phase 2. By inhibiting calcium influx into myocardial cells, calcium channel blockers can alter the excitability and conduction of cardiac tissues. 

Selectivity Ability to distinguish the analyte from interferances... 

DNA base sensors for detection of biological agents have the advantages of high sensitivity, selectivity, ability to operate in turbid media, and to be amenable to miniaturization (Shah and Wilkins 2003). The biological agents include bacteria, viruses, and toxins that may be aerosoled deliberately in air, food, or water to spread terrorism and cause disease or death to humans, animals, or plants. 

In the second place, the enzyme can make distinctions between isomers. In fact, nowhere is the selection ability of enzymes so manifest as in the ability to distinguish between isomeric structures. The various possibilities for a given number of atoms may be examined systematically. Thus, we can imagine the enzyme confronted with two materially identical molecules, making yes/no decisions in accordance with a defined classification chart. The enzyme asks Can the two molecules be superposed Arrows from the left sides of the diamonds indicate a yes answer from the right sides the arrows represent no (see Scheme 1). The possibility of superposition is... 

Selectivity Ability of the sensor device to detect only one parameter and/or discriminate between different substances in a sample. Primarily dependent upon recognition element. Arrays are often used to compensate when selectivity is not assured. 

If the temperature and pressure of a substance are above the critical point, that substance is a supercritical fluid. Many supercritical fluids are used for their very effective and selective ability to dissolve other substances. This is very true of carbon dioxide. CO2 can be made into a supercritical fluid at a relatively low temperature and pressure, so little energy is used in preparing it. Supercritical CO2 is cheap, nontoxic, and nonflammable and is easy to remove. 

In the extraction of undesirable constituents from petroleum fractions, Francis (13) has shown the usefulness of this attack, and has critically reviewed earlier compilations of C.S.T. data. The selective solvent ability of aniline is frequently used as an indication of the effectiveness of such extraction processes, and the so-called aniline point is a measure of this. Aniline point is defined as the temperature at which a mixture of equal volumes of aniline and hydrocarbon separates into two saturated liquid layers. While this is not necessarily the C.S.T. since the solubility curves are not exactly symmetrical, Francis has shown that it will approximate it very closely. A large number of aniline points for different hydrocarbons have been recorded, as well as the C.S.T. s of hydrocarbons with other solvents (13, 36). Francis has used essentially the difference in C.S.T. for a solvent with two types of hydrocarbons as an indication of the selectivity of the solvent in separating the hydrocarbons and has shown the effect on this of chemical structure of the solvent. Similarly, Drew and Hixson (10) and Hixson and Bockelmann (16) have shown the relationship between C.S.T. of propane with various fatty acids and their esters and the selective ability of propane as a solvent in separating them. 

Bakker et al. reported this method improving the limit of detection during a thin-layer coulometric analysis [12-14]. An ionophore was doped enhancing the ion-selective ability of a thin-layer membrane. Using a thin-layer coulometry coupling with double-pulse technique, the analysis of nitrate (NOsOi potassium (K" ), Calcium (Ca" ) were successfully undertaken in the scale of micromolar (pM). Furthermore, the advanced compensation of non-faradic charging... 

Methods for identification of amphetamine and methamphetamine in nrine have been employed using GC/Fourier transform IR (GC/FTIR) spectroscopy (104) however these are not widely used. These methods have provided identification of the amphetamines and metabolites at the low picogram levels. Developments in cryogenic sample deposition for GC/FTlR spectroscopy have allowed the highly selective ability of IR spectroscopy to be used for identification and quantification of these drugs. 

In addition, improvements in immunization protocols such as suppression of dominant responses, in vitro or intrasplenic immunization, and antigen-targeting have also been developed. Suppression of dominant immune responses is used to permit the expression of antibody-producing cells with specificity for poor immunogens and is achieved using the selective ability of cyclophosphamide to dampen the immune response to a particular antigen, followed by subsequent immunization with a similar antigen. 

The term receptor expresses nothing more than the idea postulating for the action of certain drugs at molecular level, the existence of specific target sites characterized by a selective ability to bind a specifically arranged drug molecule... 

The selective ability of higher-valent metal ions to oxidize organic free radicals has been examined and two mechanisms have been proposed for the decomposition of cerium(iv) carboxylates in the presence of olefins and aromatic hydrocarbons (i) involving a non-decarboxylative route with the generation of carboxyalkyl radicals via thermal decomposition, and ( ) the formation of alkyl radicals and COg in the decarboxylation reaction. E.s.r. studies using cerium(iv) have been used to provide evidence for the formation of the sulphite radical anion SO3 in the oxidation of sulphite. ... 

The cure chemistry of VDF-based fluoroelastomers is connected with the strong polarity of the C-F bond and specific polarization of molecules, which determine their selective ability to split off hydrogen fluoride under the influence of internal factors. 

The optically active secondary polyamine(PLE) seems to have a weaker selecting ability compared with linear tertiary polyamine PLIE. An optical purity of 2.5% was observed in racemic salt and achiral bromide. Thus optical activity was observed in both the product esters from the reaction of racemic salt and achiral bromide and vice versa. This fact seems to suggest that the enantio-selection has occurred by the activation of carboxylate in the reaction of racemic salt and achiral bromide by PLIE or PLE, and by quaternization of alkyl bromide in the reaction of achiral salt and racemic bromide. 

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