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181.
There have been few prospective studies of the impact of workplace interventions on employee and organizational well-being within health care settings. This study was conducted at a large regional hospital in Sweden in 1994 with a follow-up in 1995. Effects of a structured organizational and staff intervention program on perceived psychosocial work quality, supporting resources and self-reported health and well-being were evaluated. Based on department-specific results from the baseline assessment in 1994, each department formulated their own improvement goals. They also made their own decisions on relevant improvement activities. Since there was no formal reference group in this study, departments with high and low rating levels, respectively, with regard to intervention activities were compared. Despite an overall worsening in most of the measures most likely due to a notice of 20% staff reduction prior to the follow-up assessment, the intervention appeared to have attenuated negative changes in the high as compared with the low activity group. Manager-rated impact of the program as well as positive staff attitudes and staff involvement in the enhancement process were identified as important determinants for more favourable changes. The study points out the relevance of structured workplace interventions for organizational and employee well-being especially in times of cut-backs and organizational turmoil. Department-specific factors will determine the impact of such programs. The study indicates that the psychosocial impact of personnel cut-backs in health care may be attenuated through management initiatives. 相似文献
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JC S?rensen B Mattsson A Andreasen BB Johansson 《Canadian Metallurgical Quarterly》1998,812(1-2):265-269
The study was undertaken to determine if the levels of vesicular zinc in neuronal terminals would decrease in response to focal brain ischemia. The middle cerebral artery was occluded distal to the striatal branches in male spontaneously hypertensive rats. At 7, 15, 30, 45, 60, 90, 120 min; 3, 6, 12, 24, 48 h and 7 days later the animals were sacrificed and the brains were stained for zinc-sulfides, cell bodies and AChE-positive cholinergic fibers. The density of zinc positive terminals significantly decreased in the neocortical ischemic zone 7 min after middle cerebral artery occlusion (MCAO). In the neocortical layers II and III most zinc positive neuronal terminals disappeared at 7 min after MCAO whereas the zinc positive terminals in layers V and VI remained positive at least 2 h. Beginning at 1 h after MCAO and progressing to 24 h a significant decrease in the density of zinc positive terminals was observed in the dorsolateral striatum, and ventrobasal thalamic nucleus, both major projection areas of the sensorimotor cortex. The disappearance of zinc positive neuronal terminals in the ischemic neocortex and related areas, is most likely due to a neuronal release of vesicular zinc in response to hypoxia. The high extracellular concentration of zinc is thought to be both neuroprotective by blocking the NMDA receptor and neurotoxic by activating neuronal influx of Ca2+ through voltage gated calcium channels. It seems evident that the latter effect of zinc is contributing to the neuronal death in focal brain ischemia. 相似文献
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AIM: To evaluate the effect of PD Plus on weekly Kt/Vurea and creatinine clearance (Kcr) among patients undergoing CAPD/CCPD (continuous ambulatory peritoneal dialysis/continuous cyclic peritoneal dialysis). METHODS: The kinetic studies of 92 CAPD and 18 CCPD patients who transferred to PD Plus were analyzed. All patients underwent CAPD/CCPD and PD Plus for a minimum of 3 months. Standard collection methods were used and kinetic indices calculated with the Pack PD Kinetic Modeling program. 57 patients had transport data and were modeled for a target weekly Kt/Vurea >/=2.1 using PD Plus with =15 liters dialysate/day. 6 patients were supervised during the collection periods by research nurses. The actual results for all patients (110) and for the supervised patients were compared against the modeled results. RESULTS: [table] 45% of the patients achieved a Kt/Vurea >/=2.1 and 47% a Kcr >/=60 liters/1.73 m2 with PD Plus, but only 20% did so with CAPD/CCPD. A close correlation between the supervised patients and modeled therapy was observed. CONCLUSIONS: Adequate dialysis is possible by using higher fill volumes, the supine position, and optimal dwell times (PD Plus) in most patients. The discrepancy between modeled and achieved dose is likely due to poor compliance with therapy, inadequate training, or poor specimen collection. 相似文献
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Bovine pericardium (BP) is extensively used for the production of heart valve bioprostheses. BP has excellent mechanical properties but a limited lifespan because of intrinsic subsurface calcification in vivo. In this study, the in vitro mineralization of BP was investigated by a novel diffusion cell model. In two sets of experiments, glutaraldehyde-treated BP membranes were placed between two compartments, both of which contained calcium phosphate solutions made by equilibration of octacalcium phosphate (Exp I) or dicalcium phosphate dihydrate (Exp II) in phosphoric acid. The movement of calcium (Ca), phosphate (P), and protons through the BP membrane was followed throughout the diffusion process. Histology, scanning electron microscopy, wet chemical analysis, and energy dispersive X-ray analyses provided good evidence of subsurface mineralization of BP that resembled in vivo mineral deposition. Energy dispersive x-ray microanalyses found a Ca/P heterogeneity of the early subsurface mineral that formed in the membrane. The use of a diffusion cell to model BP calcification under well-characterized conditions has led to in vitro mineralization that more closely matches that observed in vivo. The results suggest that this in vitro diffusion model can be used to study the mechanism of pathological mineralization. This model has the potential to provide rapid, inexpensive, basic information about the mineralization process. 相似文献
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Widespread use of implantable cardioverter defibrillators (ICDs) for the treatment of ventricular tachycardia (VT) and ventricular fibrillation (VF) occurred in the late 1980s and early 1990s. Additionally, there has been increasing appreciation during this time for both the lack of efficacy and proarrhythmic activity of antiarrhythmic drugs to treat these cardiac arrhythmias. We evaluated the use of antiarrhythmic drugs from 1987 to 1991 (5-year period) at the time of ICD implantation in 25,450 patients. The use of all classes of antiarrhythmic agents decreased from 61% to 24% during this time period (P < 0.05). In addition, there was a significant reduction in antiarrhythmic agent use for each drug class (P < 0.05) with the exception of Class II agents (beta blockers). These changes in drug use occurred independent of any changes in age, sex, ejection fraction, prevalence of coronary artery disease, or type of ventricular arrhythmia (VT vs VF). 相似文献