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A nonselective

Classification of P2 purinoceptors has been limited by a lack of potent, selective, and bioavailable antagonists. Nonetheless a rational scheme for P2 purinoceptor nomenclature divides P2 receptors into two superfamilies P2Y5 LGIC family having four subclasses and P2Y) a GPCR family having seven subclasses. A third receptor type, designated the P22) is a nonselective ion pore. [Pg.525]

Steam Cracking. Steam cracking is a nonselective process that produces many products from a variety of feedstocks by free-radical reactions. An excellent treatise on the fundamentals of manufacturing ethylene has been given (44). Eeedstocks range from ethane on the light end to heavy vacuum gas oil on the heavy end. All produce the same product slate but in different amounts depending on the feedstock. [Pg.366]

Propranolol. Propranolol hydrochloride, considered the prototype of the P-adrenoceptor blocking agents, has been in use since 1964. It is a nonselective, highly Hpid-soluble P-adrenoceptor blocker having no ISA. It is a mixture of (+) and (—) enantiomers, and the (—) enantiomer is the active moiety. The local anesthetic effects of propranolol are equipotent to those of Hdocaine [137-58-6] C 4H22N20, (see Anesthetics). Therapeutic effects include termination of catecholamine-induced arrhythmias, conversion of SA nodal tachycardias (including flutter and fibrillation) and AV nodal tachyarrhythmias to normal sinus rhythm, digitahs-induced arrhythmias, and ventricular arrhythmias (1,2). The dmg also has cardioprotective properties (37,39). [Pg.119]

Elestolol sulfate is a nonselective, ultrashort acting P-adrenoceptor blocker. It has no ISA and produces weak inhibition of the fast sodium channel. The dmg is under clinical investigation for supraventricular tachyarrhythmias, unstable angina, and acute MI. In humans, flestolol has hemodynamics and electrophysiologic effects similar to those of other P-adrenoceptor blockers. The pharmacokinetics of flestolol are similar to those of esmolol. It is 50 times more potent than esmolol and the elimination half-life is 7.2 min. Recovery from P-adrenoceptor blockade is 30—45 min after stopping iv infusions. The dmg is hydrolyzed by tissue esterases and no active metabohtes of flestolol have been identified (41). [Pg.119]

The photolytic and thermolytic decomposition of azides in the presence of olefins has been applied to aziridine synthesis. However, only a limited number of steroid aziridines have been prepared in this manner. The patent literature reports the use of cyanogen azide at ca. 50° for 24 hours in ethyl acetate for the preparation of an A-nor- and a B-norsteroidal aziridine. The addition is believed to proceed via a triazoline. The reaction of cholest-2-ene with ethyl azidoformate takes place in a nonselective manner to produce a mixture of substances, including C—H insertion products. [Pg.30]

Wahler, m. chooser selector elector, voter, wahlerisch, a. particular, fastidious, wahl-frei, a. optional, -los, a. nonselective, random. [Pg.500]

For the separation of racemic mixtures, two basic types of membrane processes can be distinguished a direct separation using an enantioselective membrane, or separation in which a nonselective membrane assists an enantioselective process [5]. The most direct method is to apply enantioselective membranes, thus allowing selective transport of one of the enantiomers of a racemic mixture. These membranes can either be a dense polymer or a liquid. In the latter case, the membrane liquid can be chiral, or may contain a chiral additive (carrier). Nonselective membranes can also... [Pg.126]

TRPVl, also known as the capsaicin- or vanilloid-receptor, is a nonselective cation channel expressed e.g., in neurons of the dorsal root and trigeminal ganglions, which integrates multiple pain-producing stimuli including heat, protons, capsaicin, and resiniferatoxin. In addition, TRPVl currents can be activated by ananda-mide, protein kinase C (PKC), and by hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). [Pg.1246]

TRPV4, also known as TRP 12, OTRPC4 or VROAC, is a nonselective cation channel, predominantly... [Pg.1246]

AB diblock copolymers in the presence of a selective surface can form an adsorbed layer, which is a planar form of aggregation or self-assembly. This is very useful in the manipulation of the surface properties of solid surfaces, especially those that are employed in liquid media. Several situations have been studied both theoretically and experimentally, among them the case of a selective surface but a nonselective solvent [75] which results in swelling of both the anchor and the buoy layers. However, we concentrate on the situation most closely related to the micelle conditions just discussed, namely, adsorption from a selective solvent. Our theoretical discussion is adapted and abbreviated from that of Marques et al. [76], who considered many features not discussed here. They began their analysis from the grand canonical free energy of a block copolymer layer in equilibrium with a reservoir containing soluble block copolymer at chemical potential peK. They also considered the possible effects of micellization in solution on the adsorption process [61]. We assume in this presentation that the anchor layer is in a solvent-free, melt state above Tg. The anchor layer is assumed to be thin and smooth, with a sharp interface between it and the solvent swollen buoy layer. [Pg.50]

Pinocytosis is a property of all cells and leads to the cellular uptake of fluid and fluid contents. There are two types. Fluid-phase pinocytosis is a nonselective process in which the uptake of a solute by formation of small vesicles is simply proportionate to its concentration in the surrounding extracellular fluid. The formation of these vesicles is an extremely active process. Fi-... [Pg.429]

A homonuclear spin-system may be excited with radiofrequency (r.f.) pulses that are so Intense (in the order of p.s), compared to the frequency width of the spectrum, that all resonances are excited essentially uniformly. This is a nonselective excitation. A homonuclear spin-system may also be excited with a relatively weak, r.f. pulse (in the order of ms), in the sense that all components of a given multiplet are inverted at time zero, whereas the other resonances in the spectrum remain essentially unperturbed this is a selective excitation. The r.f. pulse may be single-selective, that is, there is an inversion of one multiplet in the spectrum, or double-selective, triple-selective, and so on, where two, three, or more separate multiplets in the spectrum are inverted simultaneously while the remaining resonances remain unperturbed. [Pg.128]

It has been proposed " that the mechanism(s) of action of gymnemic acids and ziziphins is a biphasic, model-membrane penetration-process. The model suggested that the modifier molecules interact first with the receptor-cell plasma-membrane surface. It was postulated that this initial interaction involves a selective effect on taste perception, including the transduction and quality specification of the sweet stimuli, and selective depression of sweetness perception. Following the initial interaction, the modifier molecules interact with the membrane-lipid interior to produce a general disruption of membrane function and a nonselective effect on taste... [Pg.337]

Presaturation Selective irradiation of a nucleus prior to application of a nonselective pulse causes it to be saturated, so its resonance is suppressed. This technique may be employed for suppressing solvent signals. [Pg.418]

The analgesic effects of NSAIDs are attributed to inhibition of the COX-2 enzyme, whereas the negative GI effects are due to inhibition of COX-1.28 Patients taking oral anticoagulants, those with a history of peptic ulcer disease, or others at high risk for GI complications may be considered candidates for a COX-2 inhibitor or a combination of a nonselective NSAID with a gastroprotective agent such as a proton pump inhibitor (PPI). Because most PPIs are available by prescription only, such patients should be referred to a physician. [Pg.904]

TRPV1 is a nonselective cation channel predominantly expressed in sensory neurons and activated by capsaicin, heat (>42°C), pH (<5.4), and noxious stimuli. Several compounds have advanced into clinical development and have been extensively covered in recent reviews [5,34—39]. Among these, MK-2295 (structure not disclosed), AMG 517 (38), SB-705498 (39), and GRC-6211 (structure not disclosed) have reportedly encountered safety issues [35]. In phase II clinical trials with MK-2295, patients experienced an increase in core body temperature... [Pg.42]

In use, SAND is first reacted with an amine-containing protein or other molecule—being careful to protect the photoreactive group from inadvertent degradation by exposure to excessive room light or sun. The modified intermediate then is allowed to interact with a target molecule. Finally, the photolyzing process is done to effect a nonselective crosslink between the... [Pg.313]

Compared to photoluminescence processes, no external light source is required, which offers some advantages such as the absence of scattering or background photoluminescence signals, the absence of problems related to instability of the external source, reduction of interferences due to a nonselective excitation process, and simple instrumentation. [Pg.48]

For OA patients who need an NSAID but are at high risk for GI complications, the ACR recommendations include either a COX-2 selective inhibitor or a nonselective NSAID in combination with either a proton pump inhibitor or misoprostol. [Pg.28]


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See also in sourсe #XX -- [ Pg.31 ]




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Nonselective

Nonselectivity

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