Selective blocking

Products of the described type have very high quality requirements as the consumers are typically families with children or restaurants catering to same, where even the smallest bones are unacceptable. Previously, sample tests were conducted on selected blocks. The blocks were thawed and sieved. This was a very slow way of inspection where the production line had to wait for the raw material. 

The drug SC-558 acts by a fourth mechanism, specifically inhibiting COX-2. It is a weak competitive inhibitor of COX-1 but inhibits COX-2 in a slow, time-dependent process. Specific COX-2 inhibitors will likely be the drugs of the future because they selectively block the inflammation mediated by COX-2, without the potential for stomach lesions and renal toxicity that arise from COX-1 inhibition. 

Narcotic antagonist. A drug that selectively blocks the actions of morphine-like compounds. 

The primary OH group can be selectively blocked by the bulky triphenyl-methyl (trityl) moiety, followed by esterification at the secondary OH groups and removal of the protecting trityl group. Thus 2,3-di-O-acetyl cellulose has been obtained by this procedure. Moreover, regioselectively substituted mixed cellulose esters, acetate/propionate, were prepared by subsequent acy-... 

B was also obtained from equilibrium-swelling data of selected block copolymers the results showed excellent agreement with the other methods (Equations 7.1 and 7.2)7... 

Richelson, E and Pfenning, M (1984) Blockade by antidepressants and related compounds of biogenic amine uptake into rat brain synaptosomes most antidepressants selectively block noradrenaline uptake. Eur. J. Pharmacol. 104 277-286. 

Sofia, R.D. Structural relationship and potency of agents which selectively block mouse killing (muricide) behavior in rats. Life Sci 8 1201-1210, 1969. 

Phencyclidine (PCP) Selectively Blocks Certain Presynaptic Potassium Channels... 

Pharmacological evidence indicates that components R, S, T, and C correspond to distinct classes of K channels (Bartschat and Blaustein 1985a Bartschat and Blaustein 1985b). Component T is blocked by low concentrations of 4 - aminopyridine (4 - A P) component C is selectively blocked by micromolar quinine sulfate, but not by 4-AP. Components R and S are much less sensitive to both drugs. 

The dose-response curves for the effects of PCP on components S and T are illustrated in figure 2. Note that low doses of PCP selectively blocked a portion (about one-third) of component S (Sv) higher doses inhibited T, as well, with but little additional effect on S. 

There is ample precedent for a modulatory role of K channels in behavior. The K channel blocker, 4-AP, selectively blocks component T (Bartschat and Blaustein 1985a). prolongs nerve action potentials, and enhances neurotransmitter release (Llinas et al. 1975). In man, intoxication with this agent may lead to dissociative behavior, agitation, confusion, convulsions, and coma (Spyker et al. 1980). However, the behavioral aberrations induced by 4-AP differ qualitatively from those induced by PCP. This implies that block of various types of presynaptic K channels may modify behavior and mental activity however, the precise nature of the behavioral manifestations is likely to depend upon the specific type of K channel that is affected. 

Bartschat, D.K. Sorensen, R.G. and Blaustein, M.P. Psychotomimetic "sigma opiates" and phencyclidines selectively block the same K channels in presynaptic nerve terminals. Soc Neurosci Abst. 11 316a, 1985. 

Many neurotransmitters are inactivated by a combination of enzymic and non-enzymic methods. The monoamines - dopamine, noradrenaline and serotonin (5-HT) - are actively transported back from the synaptic cleft into the cytoplasm of the presynaptic neuron. This process utilises specialised proteins called transporters, or carriers. The monoamine binds to the transporter and is then carried across the plasma membrane it is thus transported back into the cellular cytoplasm. A number of psychotropic drugs selectively or non-selectively inhibit this reuptake process. They compete with the monoamines for the available binding sites on the transporter, so slowing the removal of the neurotransmitter from the synaptic cleft. The overall result is prolonged stimulation of the receptor. The tricyclic antidepressant imipramine inhibits the transport of both noradrenaline and 5-HT. While the selective noradrenaline reuptake inhibitor reboxetine and the selective serotonin reuptake inhibitor fluoxetine block the noradrenaline transporter (NAT) and serotonin transporter (SERT), respectively. Cocaine non-selectively blocks both the NAT and dopamine transporter (DAT) whereas the smoking cessation facilitator and antidepressant bupropion is a more selective DAT inhibitor. 

The IR probe radiation, provided by a liquid N2-cooled line-tunable CO laser, is passed through the cell collinearly or almost collinearly with the uv photolysis radiation. The probe beam is then directed onto an IR detector using a filter for either selectively blocking the photolysis beam or... 

The trans/cis ratio of hexadiene is also increased by addition of aluminum cocatalysts containing —OR or —NR groups. It is proposed that this is due to selective blocking of a coordination site on the nickel by the formation of an intermediate such as 31, and this too would favor the formation of the transoid structure. 

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