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1.
Autoradiographic techniques were used to test if positive modulators of AMPA-type glutamate receptors have regionally differentiated effects on ligand binding. Cyclothiazide, a drug with ten fold greater effects on `flip' than `flop' splice variants of the receptors, had unequal effects across the subdivisions of hippocampus; i.e., it reduced [3H]AMPA binding in field CA3 with an EC50 of 24 μM and in field CA1 and dentate gyrus with EC50s between 60 and 100 μM. The EC50 for the drug's influence on binding was also significantly lower in the superficial than in the deeper layers of the neocortex, though these differences were not as pronounced as those in the hippocampus. The ampakine CX614, a compound with a modest preference for flop variants, had a slightly lower EC50 for its effects on [3H]AMPA binding in CA1 than in CA3. This result was confirmed with [3H]fluorowillardiine binding. The effects of the ampakine in neocortex tended to be greater in the deeper than superficial layers but this did not reach statistical significance. These results indicate that differential effects of modulators on AMPA receptor subunits are reflected in their relative potency across brain subdivisions. This raises the possibility that subclasses of positive modulators will exhibit a measurable degree of selectivity in their physiological and behavioral influences.  相似文献   
2.
Bipolar disorder (BD) is a chronic illness with high morbidity and mortality. Pediatric onset BD has a more severe course of illness with higher rates of relapse and psychosocial impairment. Discovering interventions early in the course of BD in youth is paramount to preventing full illness expression and improve functioning in these individuals throughout the lifespan. It is therefore important to understand the mechanisms involved in the development of BD in order to determine which youth are at most risk and provide biological targets for early intervention. To serve this cause, we propose a neurodevelopmental model of BD, based on the existing data that implicate prefrontal - subcortical network dysfunction, caused by pre-existing genetic susceptibility and triggered by pathological reactions to stress and chronic inflammatory processes.  相似文献   
3.
Using the inherent spatial and temporal variability within a field to manage farm operations is called precision agriculture. This is a site-specific approach which can reduce input costs and results in higher crop productivity, profitability and lesser environmental pollution. Remote sensing provides a means for the development of weed maps by detecting the location of weeds within an agricultural field, so that site-specific/need based herbicide can be applied. Reductions in herbicide use as a result of this practice reduce management costs for farmers and promote environmental friendliness. The results revealed a decreasing trend in the number of tillers, effective tillers, number of grains per ear, 1,000-grain weight and grain yield of wheat with increasing population densities of Rumex spinosus (from 3 to 12 plants m?2). Highest grain yield of wheat (5.75 tonnes ha?1) was recorded under solid stand of wheat and lowest grain yield was recorded in treatments having 12 plants of R. spinosus. Higher radiance ratio and NDVI values were recorded in solid stand or pure wheat treatment and minimum under solid weed plots. It was observed that by using radiance ratio and NDVI, pure wheat can be distinguished from pure populations of R. spinosus after 30 DAS. It remains distinguished upto 120 DAS. Different levels of Rumex populations can be discriminated amongst themselves from 60 DAS onwards.  相似文献   
4.

Background

Emergency departments see uniquely large numbers of patients across all demographic groups who are more likely to smoke and who attend with acute health concerns that can provide an impetus for behaviour change. Despite this potential opportunity, no smoking cessation programme in any UK emergency department yet exists. This study sought to identify perceived barriers and facilitators for emergency department smoking cessation activity, as well as potential modes of intervention, by exploring staff attitudes.

Methods

16 members of staff from the Emergency Department, Derby NHS Teaching Hospital were purposively sampled to include a spectrum of clinical and non-clinical roles, grades, and employment duration. Semi-structured interviews were conducted within the department, and thematically analysed with dual-coding for validity under an interpretivist paradigm.

Findings

Three themes were identified: roles of emergency departments, effects of smoking, and scope for intervention. Effects were described in individual-health and department-management contexts, with belief that reducing patient smoking would benefit both. Health promotion was seen as theoretically part of, and practically achievable within, the emergency department role. Lack of organisational support was a key barrier. Staff practice included occasional ad-hoc smoking cessation activity, but nothing routine. Those who did not incorporate smoking cessation into their practice felt that lack of training and support, rather than time, stopped them from doing so.

Interpretation

Support for emergency department smoking cessation was found in the face of major barriers. Options to address these barriers were suggested, highlighting a willingness to engage. Complex interventions appeared impractical, and no single approach seemed universally applicable to emergency department environments. This study addresses the paucity of evidence around emergency department attitudes towards smoking cessation by providing a unique and in-depth picture of staff in the study department. It also balances clinical and population health viewpoints and has potential to inform promising prevention strategies in the emerging population-focused health-care structures. However, the study might not be generalisable to other emergency departments. Further research exploring patient attitudes would be a valuable next step.

Funding

Health Education East Midlands.  相似文献   
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ObjectivePatients with obesity may experience less patient-centered care. We assessed whether medical students’ implicit/explicit weight-related attitudes and perceptions of normative attitudes are associated with patient-centered care for patients with obesity.MethodsThird and fourth year medical students (N = 111) at one medical school completed a survey and participated in a patient care scenario with a standardized patient with obesity. Encounters were coded for patient-centered behavior. Predictors of patient-centered behaviors were assessed.ResultsStudent perceptions that negative attitudes about patients with obesity are normative in medical school were significantly associated with poorer patient-centered behaviors, including lower attentiveness (b=?0.19, p = 0.01), friendliness (b=?0.28, p < 0.001), responsiveness (b=?0.21, p = 0.002), respectfulness (b=?0.17, p = 0.003), interactivity (b=?0.22, p = 0.003), likelihood of being recommended by observers (b=?0.34, p < 0.001), and patient-centeredness index scores (b=?0.16, p = 0.002). Student reported faculty role-modeling of discrimination against patients with obesity predicted lower friendliness (b=?0.16, p = 0.03), recommendation likelihood (b=?0.22, p = 0.04), and patient-centeredness index score (b=?0.12, p = 0.03).ConclusionsNegative normative attitudes and behaviors regarding obesity in the medical school environment may adversely influence the quality of patient-centered behaviors provided to patients with obesity.Practice implicationsEfforts to improve patient-centered communication quality among medical trainees may benefit from intervention to improve group normative attitudes about patients with obesity.  相似文献   
8.
Herein, well dispersed Ag–Cu NPs supported on modified graphene have been synthesized via a facile and rapid approach using sodium borohydride as a reducing agent under ambient conditions. Dicyandiamide is selected as an effective nitrogen source with TiO2 as an inorganic material to form two kinds of supports, labelled as TiO2–NGO and NTiO2–GO. Initially, the surface area analysis of these two support materials was carried out which indicated that N-doping of GO followed by anchoring with TiO2 has produced support material of larger surface area. Using both types of supports, ten nano-metal catalysts based on Ag and Cu were synthesized. Benefiting from the bimetallic synergistic effect and larger specific surface area of TiO2–NGO, Cu@Ag–TiO2–NGO is found to be a highly active and reusable catalyst out of other synthesized catalysts. It exhibits excellent catalytic activity for oxidation of alcohols and hydrocarbons as well as Chan–Lam coupling reactions. The nanocatalyst is intensively characterized by BET, SEM, HR-TEM, ICP-AES, EDX, CHN, FT-IR, TGA, XRD and XPS.

Cu@Ag–TiO2–NGO prepared from modified graphene by simple methodology exhibits enhanced catalytic activity towards oxidation and Chan–Lam coupling due to the synergistic effect between Ag and Cu NPs.  相似文献   
9.
The transportation of sputum samples may sometimes take more than one week which results in an increased contamination rate and loss of positive cultures. The current study was planned to analyze the recovery rate of mycobacteria from transported samples with and without Cetylpyridinium chloride (CPC). Addition of CPC is useful for isolation of M. tuberculosis from sputum subjected to long-term storage.  相似文献   
10.
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