972 resultados para OH^-


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In addition to its hyperphagic effect in rats, 8-OH-DPAT also reduces grooming, but it is uncertain whether the inhibition of grooming is a specific effect or a consequence of response competition from eating. The present experiments explored the effects of 8-OH-DPAT on periprandial grooming and grooming elicited by spraying rats with water. Momentary time sampling over 30 or 60 min, with behaviour scored in one of 6 or 7 (depending on food availability) mutually exclusive categories (feeding, active, scratching, face grooming, body grooming, genital grooming and resting) at 15s intervals, was used for data collection. Non-deprived rats were tested in the presence and absence of food and baseline grooming levels were manipulated by spraying the dorsal surface of the back with water. Data were submitted to ANOVA. The first experiment confirmed that 8-OH-DPAT increased food intake and that this was associated with a parallel increase in feeding observations; active observations were also increased, but resting and total grooming observations were reduced: scratching was reduced even at 0.003mg/kg, face- and body-grooming were reduced at doses > 0.03mg/kg and genital-grooming was least sensitive, only being reduced at 0.1mg/kg. The second experiment revealed that spraying with water had no effect on food intake, feeding or resting observations, but increased total grooming (largely due to increased body-grooming) and reduced activity observations. In rats sprayed with water, 8-OH-DPAT increased food intake (0.1mg/kg) and observations of feeding (0.003 & 0.1mg/kg), but total grooming was dose-dependently inhibited, with genital-grooming most sensitive(> 0.003mg/kg), followed by face-grooming (> 0.01mg/kg) and body-grooming (>0.03mg/kg), whilst low levels of scratching were unaffected. The final experiment tested water-sprayed rats in the absence of food: 8-OH-DPAT increased resting and reduced total grooming, mostly as a consequence of reductions in face- and body-grooming, but there were also modest reductions in scratching. These results confirm that 8-OH-DPAT has a suppressant effect on all aspects of grooming, except where there are probable floor effects, and that this is independent of response competition from increased eating.

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The effects of 8-OH-DPAT treatment on rat grooming behaviour, elicited either prandially or in response to spraying with water were investigated. Dose (≤0.1 mg/kg s.c.) response studies employed momentary time sampling over 30 or 60 min with behaviour being scored in one of 6 or 7 (depending on food availability) mutually exclusive categories (feeding, active, scratching, face-grooming, body grooming, genital-grooming and resting) at 15 s intervals. In non-deprived rats, tested with wet mash available, feeding and activity frequencies were increased, but resting and total grooming were inhibited by 8-OH-DPAT. Face-, body- and genital-grooming occurred at higher levels than scratching, but all categories were reduced with reductions in scratching occurring at a lower dose (0.01 mg/kg). Misting rats with a fine water spray selectively increased body grooming and decreased activity without altering feeding, while 8-OH-DPAT increased feeding and reduced face-, body- and genital-grooming, without affecting already low levels of scratching. In misted rats, tested without food, 8-OH-DPAT reduced face-, body- and genital-grooming and increased resting. These results confirm i) that the water spray technique is a useful method for increasing grooming and ii) that 8-OH-DPAT has a suppressant effect on grooming independent of response competition from enhanced feeding.

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Oestrogen produces diverse biological effects through binding to the oestrogen receptor (ER)(1). The ER is a steroid hormone nuclear receptor, which, when bound to oestrogen, modulates the transcriptional activity of target genes(2). Controversy exists, however, concerning whether ER has a role outside the nucleus(3), particularly in mediating the cardiovascular protective effects of oestrogen(4). Here we show that the ER isoform, ER alpha, binds in a ligand-dependent manner to the p85 alpha regulatory subunit of phosphatidylinositol-3-OH kinase (PI(3)K). Stimulation with oestrogen increases ER alpha-associated PI(3)K activity, leading to the activation of protein kinase B/Akt and endothelial nitric oxide synthase (eNOS). Recruitment and activation of PI(3)K by ligand-bound ERa are independent of gene transcription, do not involve phosphotyrosine adapter molecules or src-homology domains of p85 alpha, and extend to other steroid hormone receptors. Mice treated with oestrogen show increased eNOS activity and decreased vascular leukocyte accumulation after ischaemia and reperfusion injury. This vascular protective effect of oestrogen was abolished in the presence of PI(3)K or eNOS inhibitors. Our findings define a physiologically important non-nuclear oestrogen-signalling pathway involving the direct interaction of ERa with PI(3)K.

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Liquid ethanol (C2H5OH) was used to generate a spray of sub-micron droplets. Sprays with different nozzle geometries have been tested and characterised using Mie scattering to find scaling properties and to generate droplets with different diameters within the spray. Nozzles having throat diameters of 470 µm and 560 µm showed generation of ethanol spray with droplet diameters of (180 ± 10) nm and (140 ± 10) nm, respectively. These investigations were motivated by the observation of copious negative ions from these target systems, e.g., negative oxygen and carbon ions measured from water and ethanol sprays irradiated with ultra-intense (5 × 1019 W/cm2), ultra short (40 fs) laser pulses. It is shown that the droplet diameter and the average atomic density of the spray have a significant effect on the numbers and energies of accelerated ions, both positive and negative. These targets open new possibilities for the creation of efficient and compact sources of different negative ion species.

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Serotonin (5-HT) receptor agonists have been reported to produce mydriasis in mice, and miosis in rabbits and humans. However, the underlying mechanisms for this action are unclear. This study was undertaken in an attempt to explore the mechanism by which 5-HT receptors are involved in the modulation of pupillary size in pentobarbital-anesthetized rats. Intravenous administration of the 5-HT receptor agonist, (2R)-(+)-8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT; 0.003-3 mg/kg), elicited dose-dependent pupillary dilation, which was not affected by section of the preganglionic cervical sympathetic nerve. 8-OH-DPAT-elicited mydriatic responses were attenuated by the selective 5-HT receptor antagonist, N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2- pyridinylcyclohexanecarboxamide maleate (WAY 100635; 0.3-1 mg/kg, i.v.), as well as by the selective a -adrenoceptor antagonist, (8aR,12aS,13aS)-5,8,8a,9,10,11,12,12a,13,13a-dechydro-3-methoxy-12- (ethylsulfonyl)-6H-isoquino[2,1-g][1,6]naphthyridine hydrochloride (RS 79948; 0.3 mg/kg, i.v.), but not by the selective a -adrenoceptor antagonist, prazosin (0.3 mg/kg, i.v.). Mydriatic responses elicited by the a -adrenoceptor agonist, guanabenz (0.003-0.3 mg/kg, i.v.), were not antagonized by WAY 100635 (0.3-1 mg/kg, i.v.). To determine whether central nervous system (CNS) 5-HT receptors, like a -adrenoceptors, are involved in reflex mydriasis, voltage response curves of pupillary dilation were constructed by stimulation of the sciatic nerve in anesthetized rats. WAY 100635 (1 mg/kg, i.v.) did not antagonize the evoked reflex mydriasis, which, however, was blocked by RS 79948 (0.3 mg/kg, i.v.). Taken together, these results suggest that 8-OH-DPAT produces pupillary dilation in anesthetized rats by stimulating CNS 5-HT receptors, which in turn trigger the release of norepinephrine, presumably from the locus coeruleus. The latter reduces parasympathetic neuronal tone to the iris sphincter muscle by stimulation of postsynaptic a - adrenoceptors within the Edinger-Westphal nucleus. Unlike a - adrenoceptors, 5-HT receptors in the CNS do not mediate reflex mydriasis evoked by sciatic nerve stimulation. © 2004 Elsevier B.V. All rights reserved.

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Aim: Foreskin surgical procedures such as circumcision, prepuceplasty, frenuloplasty, dorsal slit, reduction of paraphimosis etc. in the adult male is usually performed by both general surgeons and urologists. Our aim was to evaluate the acceptance of performing these procedures in the day procedure unit or in the emergency unit under penile block. 
Method: Fifty patients who underwent foreskin surgeries under local anaesthetic (LA) were evaluated with their experience. Twenty patients who underwent circumcision, 20 patients who underwent foreskin preserving operations such as frenuloplasty or prepuceplasty and 10 patients who underwent other procedures such as reduction of paraphimosis (five) and dorsal slit (five) were included inthe study. The patients were asked about their symptoms such as pain or discomfort during local infiltration of lignocaine, any discomfort during the actual procedure, post-operative discomfort and general acceptance. All the patients were given penile block using smaller size needle (25 gauge, 5/8th inch orange sterile luer slip hypodermic needle) and 1% plain lignocaine. Thirty doctors from general surgery (10), urology (10) and emergency medicine (10) participated in the survey. They were asked about their opinion, confidence and preference about performing foreskin surgical procedures under LA. This included both junior trainees, middle grade doctors and consultants. The majority of middle grade doctors and consultants were fairly confident in performing procedures under LA, whereas the junior trainees in surgery, urology and emergency were lacking confidence. 
Conclusion: Penile block is a safe and effective way ofproviding sufficient anaesthesia for foreskin surgeries. Thetechnique is easy to learn. It reduces post-operative pain aswell. It can reduce the risk and cost of administering generalanaesthesia. doctors who are in training surgical specialityand emergency medicine should be encouraged to learnthe principles and technique in administering penile block.

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Reduced TiO2 (110) surfaces usually have OH groups as a result of H2O dissociation at oxygen vacancy defects. Because of excess electrons due to OH adsorption, OH/TiO2. exhibit interesting properties favorable to further O-2 or H2O adsorption. Both O-2 and H2O can adsorb and easily diffuse on the OH/TiO2 surface; such behavior plays a significant role in photocatalysis, heterogeneous catalysis, electronic devices and sensors. Indeed, the processes of H2O dissociation, O-2 and H2O diffusion on Such TiO2 surfaces, in the presence of OH groups, are important issues in their own right. Herein, the most recent experimental and theoretical progresses in understanding the interactions between adsorbed OH groups and O-2, or H2O, over TiO2 (110) surfaces and their implications will be reviewed. (c) 2009 Elsevier Ltd. All rights reserved.

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This is an essay including annotated critical editions documenting the history of reception of this song since 1848. Published in the Liederlexikon for the AHRC and DFG funded project 'The History of Reception of the Songs of the 1848 Revolution' (2009-2013).

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Alors que Les fous de Bassan s’attachait à mettre en scène une Amérique métonymique tournée vers sa fin, tout se passe comme si Le premier jardin visait pour sa part à lester cette Amérique incertaine et eschatologique par l’anamnèse de son commencement, qui, chez Anne Hébert, prend le plus souvent la forme d’un re-commencement. Il s’agira ici d’interroger le dispositif temporel mis en fiction dans le roman, notamment par l’entremise d’une lecture de la pièce Oh les beaux jours et de sa temporalité figée d’après-coup. À travers cette analyse de la temporalité, on voudra également mettre en relief l’instrumentalisation de l’histoire collective par le sujet, qui cherche ainsi à se prémunir de sa propre mémoire, constamment mise à distance au sein du roman.