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STUDY OBJECTIVES: Use of fast track has been shown to improve the emergency department flow of less urgent patients. It has been speculated, however, that this could negatively affect the care of urgent patients. The objective of this study was to determine whether a dedicated fast track for less urgent patients [Canadian Triage and Acuity scale category 4/5 (CTAS 4/5)] affected (1) the time to assessment for urgent patients (CTAS 3), (2) the length of stay for less urgent patients (CTAS 4 and 5), and (3) the left-without-being-seen rate. METHODS: In June 2003, fast track was opened in our emergency department from 13:00 to 19:00 h. A before-after intervention comparison analysis was completed for 1 week in Aug 2002 and the same week in Aug 2003. Data collected included (1) time to assessment of CTAS 3 patients, (2) the length of stay for CTAS 4/5 patients, and (3) percentage of patients who left without being seen. RESULTS: A total of 368 patients were reviewed for 2002 and 380 patients were reviewed for 2003. Median time to assessment of CTAS 3 patients presenting from 13:00 to 19:00 h was reduced from 66 min (Interquartile range: 40, 94 min) in 2002 to 60 min (IQR: 38, 108 min) after fast track was open in 2003 (P = 0.95). Median length of stay of CTAS 4 and 5 patients was reduced from 170 min (IQR: 111, 256 min) to 110 min (IQR: 69, 185 min) (P < 0.001). The overall left-without-being-seen rate decreased from 5% (20/368) to 2% (9/380). CONCLUSION: A dedicated fast track for CTAS 4/5 patients can reduce the length of stay and the left-without-being-seen rate with no impact on CTAS 3 patients seen in the main emergency department.  相似文献   
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Glutamate (GLU)-receptor subtypes, (quisqualate (QA)-, kainate (KA)-, N- methyl-D-aspartate (NMDA)-receptors) and the phencyclidine sites localized in the ion-channel associated to the NMDA-receptors, were studied by autoradiography in the hippocampus of rats subjected to a convulsive dose of the acetylcholinesterase inhibitor soman (0-, 1,2,2-trimethylpropyl methylphosphonofluoridate). In intoxicated rats, a significant increase in L-[3H]-GLU binding occurred within the first 40 min of seizures in the hippocampal CA3 and CA1 areas. Whereas binding to KA- and NMDA-receptors remained unchanged, L-[3H]-GLU binding to CA3 QA-receptors increased by 31 and 50% respectively after 10 and 40 min of seizures. In CA1, the change in QA-receptors was delayed (+30% after 40 min) and accompanied by an increase in the phencyclidine site binding capacity, reflecting the probable concomitant opening of NMDA ion-channels. These findings confirmed the previously suspected involvement of GLU in the earliest stages of soman-induced seizures, and suggested that, in hippocampus, the primary activation of QA-receptors in the CA3 region could lead to the secondary recruitment of combined non-NMDA (QA) and NMDA mechanisms in CA1.  相似文献   
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Summary A simultaneous decay of the expression of Im 140 kDa, Im 150 kDa and Im 160 kDa high MW membrane antigens, concomitant with the cell proliferation arrest, was observed during erythropoietin induced differentiation ofts 34 AEV-transformed erythroid cells cultivated at the restrictive temperature. Expression of embryo-immature antigens was maintained during induced differentiation of erythroleukemia cells, but their MW shifted from 50 to 48 kDa, which corresponds to the MW of embryo-immature antigens detected on normal erythroid cells. In the absence of erythropoietin at the restrictive temperature, conditions under which thets 34 AEV-transformed erythroid cells fail to differentiate and maintain their capacity to proliferate, the expression of high MW antigens as well as the expression of embryoimmature antigens remained unaffected. Therefore, it is shown that the expression of specific membrane antigens is modulated under conditions rendering the erythroleukemia cell differentiation process possible.With 3 Figures  相似文献   
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The addition of normal mouse serum (NMS) to mouse bone marrow cell cultures was found to stimulate the growth of late erythroid precursors (CFU-E). The stimulating activity was called Erythropoietic Stimulating Cofactor (ESCF) (Blanchet et al 1984). In this article, we report that CFU-Es from foetal liver are not sensitive to serum addition, in contrast to CFU-Es from bone marrow or spleen taken from the same foetuses. When foetal liver cells were co-cultured with irradiated adult bone marrow cells, addition of NMS stimulated the foetal liver CFU-Es, suggesting that ESCF acts via some accessory cells not present (or in too low a frequency) among foetal liver cells. Moreover, NMS should be added at onset of adult bone marrow cell culture to be fully stimulatory. In addition, a very large increase (by a factor of 5 to 7) was observed for CFU-Es from spleen and bone marrow from 6- to 20-d-old newborn mice. This high sensitivity was correlated with a post-natal anaemia. We propose the existence of two different CFU-E population, one stimulated by the accessory cells, the other not, the proportion of which could be modified in response to anaemia.  相似文献   
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Acetylcholine can stimulate the release of vasopressin. In organ-cultured hypothalamo-neurohypophyseal systems, acetylcholine enhanced vasopressin release by acting in or near the supraoptic nucleus Extracellular recordings suggested that acetylcholine can increase supraoptic neuron excitability. These effects could be mimicked, in part, by nicotine or blocked by nicotinic antagonists, suggesting that they might be mediated by nicotinic acetylcholine receptors. Autoradiography indicated that alpha-bungarotoxin binding sites are present in the supraoptic nucleus; however, neither acetylcholine nor nicotine binding sites could be detected. Thus, the existence, let alone the nature, of nicotinic receptors in the supraoptic nucleus has so far remained elusive. The present work attempts to determine: (i) whether functional nicotinic receptors are present in this nucleus; (ii) whether they are located on neurosecretory magnocellular cells or at presynaptic sites; (iii) what their pharmacological and biophysical properties are; (iv) whether they influence the activity of all or only part of supraoptic neurons. Whole-cell recordings were performed in hypothalamic slices or in acutely dissociated supraoptic neurons and the effect of nicotinic agonists was tested under voltage-clamp conditions. Autoradiography was done in coronal hypothalamic sections, using [3H]epibatidine and [125I]alpha-bungarotoxin as ligands. Our results indicate that supraoptic neurons possess functional nicotinic receptors containing the alpha7 subunit.  相似文献   
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ObjectivesAcute hospitalization may lead to a decrease in muscle measures, but limited studies are reporting on the changes after discharge. The aim of this study was to determine longitudinal changes in muscle mass, muscle strength, and physical performance in acutely hospitalized older adults from admission up to 3 months post-discharge.DesignA prospective observational cohort study was conducted.Setting and ParticipantsThis study included 401 participants aged ≥70 years who were acutely hospitalized in 6 hospitals. All variables were assessed at hospital admission, discharge, and 1 and 3 months post-discharge.MethodsMuscle mass in kilograms was assessed by multifrequency Bio-electrical Impedance Analysis (MF-BIA) (Bodystat; Quadscan 4000) and muscle strength by handgrip strength (JAMAR). Chair stand and gait speed test were assessed as part of the Short Physical Performance Battery (SPPB). Norm values were based on the consensus statement of the European Working Group on Sarcopenia in Older People.ResultsA total of 343 acute hospitalized older adults were included in the analyses with a mean (SD) age of 79.3 (6.6) years, 49.3% were women. From admission up to 3 months post-discharge, muscle mass (?0.1 kg/m2; P = .03) decreased significantly and muscle strength (?0.5 kg; P = .08) decreased nonsignificantly. The chair stand (+0.7 points; P < .001) and gait speed test (+0.9 points; P < .001) improved significantly up to 3 months post-discharge. At 3 months post-discharge, 80%, 18%, and 43% of the older adults scored below the cutoff points for muscle mass, muscle strength, and physical performance, respectively.Conclusions and ImplicationsPhysical performance improved during and after acute hospitalization, although muscle mass decreased, and muscle strength did not change. At 3 months post-discharge, muscle mass, muscle strength, and physical performance did not reach normative levels on a population level. Further research is needed to examine the role of exercise interventions for improving muscle measures and physical performance after hospitalization.  相似文献   
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Older gay men experience an elevated prevalence of adverse health conditions that may be compounded by age-related deterioration. Some of these conditions may be ameliorated by regular adherence to physical activity (PA). However, many gay men participate in less PA than their age-matched heterosexual counterparts. With a focus on gay men aged 60 and over, the aims of this review were to examine the evidence for older gay men's engagement with PA and the research approaches used to describe this group. A systematic search of six academic databases (Academic Search Premier, Cinahl, PubMed, Sport Discus, APA PsychInfo and APA PsychArticles) generated 23 papers from 1970 to 2020 that focused on older gay men's engagement with PA. Although surveys were well represented in the literature, further studies utilising qualitative methodological frameworks have the potential to inform targeted interventional programs aimed at reducing less health disparities. The value of PA in older adults lies principally in improved performance of activities of daily living, independent living, increased longevity, decreased cognitive decline and improved mental well-being.  相似文献   
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