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811.
Numerous findings suggest that drug seeking and ingestive behaviors share common neurobiological mechanisms, but the relevant pathways are unknown. Dietary manipulations result in changes in endocrine the and/or neuropeptide signals, such as the hormones leptin and ghrelin, which are dynamically linked to energy balance and the regulation of feeding behavior. We have recently demonstrated that food deprivation-induced reinstatement of heroin seeking can be blocked with leptin, and others have suggested a role for ghrelin in drug-related behaviors. The feeding-relevant effects of leptin and ghrelin involve the inhibition or activation, respectively, of neuropeptide Y/agouti-related peptide (NPY/AGRP) neurons in the hypothalamus. However, the effects of NPY, a highly potent orexigenic peptide, on drug-related behaviors have not been thoroughly studied. Here we examined the effect of acute NPY administration on the rate of heroin self-administration and the reinstatement of extinguished heroin-seeking behavior. Heroin intake (0.05mg/kg/infusion) was tested using a self-administration procedure (FR-1), 10-min post-NPY injections (0.0, 4.0, and 10mug/rat, ICV). In a different group of rats, NPY-induced reinstatement (0.0, 4.0, and 10mug/rat, ICV) of extinguished heroin seeking was assessed. NPY injections increased on-going heroin self-administration, and induced a reinstatement of extinguished heroin-seeking behavior. These findings suggest that NPY can modulate the rewarding and conditioned reinforcing effects of drugs of abuse. 相似文献
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Capper SJ Ross JJ Sandström E Braidley PC Morgan-Hughes NJ 《British journal of anaesthesia》2007,98(4):442-446
Background: Transoesophageal echocardiography (TOE) can image pleural fluid.Left pleural collections may be easier to detect than right,as the thoracic aorta serves as an acoustic window. Attemptsto quantify pleural fluid using TOE are restricted to a casereport in which volume was predicted by multiplying maximalcross-sectional area (CSAmax) by axial length (AL). A computedtomography (CT) derived formula for quantifying pleural effusionsis maximal effusion depth squared (d2) multiplied by maximaleffusion length. Methods: Eight patients were studied before chest closure following coronarybypass surgery. Fifty millilitre saline aliquots were instilledinto the pleural space until detected by TOE. Saline was theninstilled up to the next 200 ml increment and further 200 mlaliquots added until it spilled from the pleural space. CSAmax,d and AL were measured for each stage and used to calculatepleural fluid volume. Results: Median detection volume (range) was 125 ml (50200) onthe left and 225 ml (150300) on the right (P = 0.016).Volume calculated by CSAmax x AL correlated strongly with actualvolume (r2 = 0.93 left and 0.92 right) as did volume calculatedby d2 x AL (r2 = 0.86 left and 0.89 right). Mean differencebetween volume calculated by CSAmax x AL and actual volume was 51 ml on the left and 45 ml on the right vs 253 ml on the left and 212 ml on the right for volumecalculated by d2 x AL. Conclusions: TOE detects small volumes of pleural fluid on both sides ofthe chest. CSAmax x AL provides a reasonably accurate measureof pleural fluid volume. 相似文献
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Mats Nilsson Johan Lökk Bo Norberg Johan Hultdin Herbert Sandström Göran Westman 《Nordic journal of psychiatry》2013,67(4):299-303
The aim of the study was to elucidate possible sex differences in knowledge, competence and attitudes behind decision-making on cobalamin-associated problems (vitamin B 12 ). The study was conducted by postal questionnaires to Swedish physicians in 1996-98. The participants were recruited by random sampling of general practitioners (1996, 1998), and a total sampling of geriatricians (1998). The overall response rate was 71%. The study group comprised 480 female physicians and 526 male physicians. The responses to 24 statements in the questionnaire were measured by means of visual analogue scales. Group differences were evaluated by medians and shapes of distributions. The female doctors appeared to value patient-related symptoms and signs more than male doctors. Conversely, male doctors relied on laboratory tests more than female doctors. As reflected by questionnaire answers, female doctors appeared to be more informed than male doctors on cobalamin-associated clinical problems. Group differences between the sexes were marginal from a numerical point of view. It is suggested that the statistical differences observed should be regarded as negligible until confirmed by further studies. 相似文献
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Wong Connie Odom Samuel L. Hume Kara A. Cox Ann W. Fettig Angel Kucharczyk Suzanne Brock Matthew E. Plavnick Joshua B. Fleury Veronica P. Schultz Tia R. 《Journal of autism and developmental disorders》2015,45(7):1951-1966
Journal of Autism and Developmental Disorders - The purpose of this study was to identify evidenced-based, focused intervention practices for children and youth with autism spectrum disorder. This... 相似文献
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Nyantara Wickramasekera Emily Strong Philip Shackley Tia Callaghan Matthew Lee Daniel Hind Steven Brown PITSTOP Project Management Group PITSTOP Collaborators 《Colorectal disease》2023,25(5):984-994