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51.
The changes of nucleic acids content in the formation of conditioned skin-defence reflex was studied on inbred rats of various strains. In WGA rats the reflex was formed on the average aight stimulations. An increased RNA content was discovered by cytophotometric determination of the nucleic acids content in the neurons and perineural glia of the cerebral cortex in August rats only. It is assumed that an increased RNA synthesis in the animals of this strain can serve as the basis for their better training.  相似文献   
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Recent studies suggest that increased lipid peroxidation and lipid peroxidation products, such as 4-hydroxynonenal (HNE), contribute to neuronal loss in conditions associated with oxidative stress. The focus of the present study was to determine possible neuroprotective effects of elevated cyclic nucleotide levels against lipid peroxidation and HNE-mediated neural toxicity. Application of 8-bromo derivative analogs of cAMP or cGMP resulted in attenuation of HNE-induced increases in mitochondrial calcium, reactive oxygen species, and neuron loss. Similar results were obtained when neural cells were pretreated with the phosphodiesterase inhibitors zaprinast or isobutylmethylxanthanine (IBMX). These data are consistent with a possible neuroprotective role for elevated cyclic nucleotide levels in disorders associated with increases in lipid peroxidation and HNE.  相似文献   
53.
In this work the A-site deficiency limit for undoped SrTiO3, calcined in air or reducing atmosphere, was investigated. XRD and SEM analyses showed that when using the solid-state synthesis route it was difficult to achieve any A-site deficiency. Even very small deviations from unity in the Sr/Ti-ratio resulted in impurity phases. The effects of Sr/Ti-ratio on the performance of SrTiO3 anodes for solid oxide fuel cells (SOFCs) was investigated by impedance spectroscopy with cone-shaped electrodes. The electrocatalytic activity of the SrTiO3 cone samples, with various amount of reduced titanium dioxide phases (Magnéli phases), was investigated for oxidation of H2 at 700 °C. High temperature treatment at 1000 °C, between the measurements at 700 °C, showed that high content of Magnéli phases leads to faster degradation of the activity. The suitability for using cone-shaped electrodes as a tool for investigating electrode materials is discussed.  相似文献   
54.
An interinstitutional study on the failed back surgery syndrome (FBSS) has determined that failure to recognize or adequately treat lateral stenosis of the lumbar spine with resultant nerve irritation and/or compression comprised the primary etiology in 57% to 58% of patients. Other common causes were recurrent or persistent disk herniation and lumbosacral adhesive arachnoiditis. The diagnosis of stenosis was made either by high-resolution CT scan of the lumbar spine or by directly testing lateral canal and for animal patency at the time of surgery. It is now appreciated that the process of degenerative disk disease, particularly when enhanced by diskectomy, results in progressive loss of intervertebral disk volume and predisposes to future ipsilateral or contralateral lateral spinal stenosis. Degenerative disk disease is ultimately a bilateral process and therefore surgical exposure should be bilateral. The direct and indirect costs of FBSS to patients and to society as well as the toll in human suffering are very high. This is particularly a matter of concern when it is realized that for many FBSS patients, surgery could have been avoided in the first place by preventive care or by innovative conservative treatment. When surgery is indicated, adequate diagnostic tests and the execution of appropriate procedures based upon this information should largely prevent the failed back surgery syndrome.  相似文献   
55.
OBJECTIVE: To examine the relative contribution of psychologic factors and physical symptoms to the variance in fatigue in older women with heart failure. METHODS: Eighty women who had been hospitalized in the previous 12 months for heart failure were interviewed. Fifty-seven women completed second interviews 18 months after the first interview. RESULTS: Fatigue was the most frequently occurring physical symptom at both measurement times, and it significantly increased with time. Other physical symptoms contributed uniquely to the variance in fatigue at both measurement times, but psychologic factors did not. At time 1, sleep difficulties, chest pain, and weakness each explained unique variance in fatigue. At time 2, dyspnea was the only variable that explained unique variance in fatigue (9%). Dyspnea also explained a significant portion of the variance (7%) in time 2 fatigue, when time 1 fatigue was controlled. CONCLUSIONS: Fatigue in older women with heart failure is related more to other physical symptoms than psychologic factors.  相似文献   
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This study evaluates the performance of boys with Attention Deficit Hyperactivity Disorder (ADHD) on the Rey-Osterrieth Complex Figure (ROCF) taking into consideration familiality and comorbid psychiatric and learning disorders (LD). Sixty-five children with ADHD performed at developmentally lower levels of Copy Organization and Recall Style than did 45 controls. ADHD children with LD scored significantly lower on Copy Organization than did ADHD children without LD, whereas psychiatric comorbidity and familiality had no effect. These results suggest that a developmental analysis of the ROCF identifies organizational difficulties associated with ADHD and that these impairments cannot simply be attributed to comorbidities associated with ADHD.  相似文献   
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In recent years considerable attention has been given to the effects of universal, first-dollar coverage for health care services as provided under Canada's health care system. However, no consideration has been given to the stability of these effects through periods of changing economic climate. In this paper we consider the extent to which the achievements of the Canadian approach to health care funding have been maintained in the presence of increasing attention to cost containment. Multivariate analyses are used to (a) explain variations in utilization of family physician services among the population and (b) explore the relationship between utilization and need for periods of differing economic circumstances. We observe that the relative importance of differences in need in explaining variations in use among the population was less in the period when cost containment was of greater concern. These findings indicate that policymakers cannot assume that removing financial barriers to access to service, although important in achieving a more equitable distribution of service utilization, may be sufficient to sustain such distributions during time of constraint.  相似文献   
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