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91.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。 相似文献
92.
The Barthel Index (BI), the Modified Barthel Index (MBI) and the Functional Independence Measure (FIM) are all widely used by occupational therapists as assessment tools for clinical decision-making and outcome measurement. All of these tools have demonstrated validity and the BI and the FIM have demonstrated inter-rater reliability. The MBI has been modified to increase sensitivity; however, there have been no publications on the inter-rater reliability of this tool following the changes. The purpose of this research was to examine the inter-rater reliability of two versions of the Barthel Index, and draw some comparisons between this assessment tool and the FIM. Twenty-five patients with neurological and orthopaedic conditions were assessed by three occupational therapists using the three tools. The method of analysis selected was percentage agreement and intraclass correlation coefficient. The results indicated that both the original and modified versions of the Barthel Index possess good inter-rater reliability. As all three tools have demonstrated adequate reliability and validity, it is suggested that clinicians select the most sensitive tool that best meets their clinical needs, and use this assessment tool in its standardized format. 相似文献
93.
Monique M. Cherrier Gary W. Small Scott Komo Asenath La Rue 《Psychiatry Research: Neuroimaging》1997,76(2-3):67-74
People undergoing medical procedures sometimes experience feelings that may influence the results. In this study, we explore the relationship between changes in mood state self-ratings and cerebral glucose metabolism during positron emission tomography (PET) in persons with age-associated memory impairment (mean age 59.4±9.8 years). Brain regions of interest involved in both mood and memory were examined. Mood ratings of increased boredom correlated significantly with mesial temporal and parietal asymmetry and decreased parietal metabolism. Mood ratings of increased fatigue correlated with basal ganglia asymmetry and the right basal ganglia and left mesial temporal metabolism. These findings suggest that subjective mood state changes during PET may influence metabolism in brain regions implicated in emotion and memory function in people with age-related memory complaints. 相似文献
94.
92例跟骨骨折后足部畸形功能障碍治疗探讨 总被引:6,自引:1,他引:5
本文对92例106足波及距下关节的跟骨骨折治疗后1~6年遗留足畸形、功能障碍的病例(PALey:舌型17足,中央压陷型53足,严重粉碎型36足)进行了分析和总结。作者强调解剖复位、牢靠固定、一期植骨、早期关节持续被动运动及不过早负重是预防跟骨骨折众多并发症的重要措施。 相似文献
95.
轻度认知障碍及阿尔茨海默病患者外周血淋巴细胞中蛋白磷酸酯酶-2A的改变 总被引:1,自引:1,他引:0
目的 探讨轻度认知功能障碍(MCI)及阿尔茨海默病(AD)患者外周血淋巴细胞蛋白磷酸酯酶-2A(PP-2A)的变化.方法 用放射性配体结合试验检测11名健康对照者、11例MCI患者及11例AD患者外周血淋巴细胞PP-2A的活性,并用Western bolt检测PP-2A蛋白的表达.结果 MCI组外周血淋巴细胞PP-2A活性(0.71±0.12)及蛋白表达(0.80±0.05)与健康对照组[分别为(1.01±0.09)和(0.96±0.07)]相比明显降低(均P<0.01);AD组PP-2A活性(0.64±0.11)及蛋白表达(0.76±0.06)亦明显降低,与对照组相比差异有统计学意义(均P<0.01);AD组PP-2A活性及蛋白表达比MCI组有降低的趋势,但差异无统计学意义.结论 MCI及AD患者外周血淋巴细胞PP-2A的活性及表达降低,在MCI的诊断中可能有参考价值,同时亦可能对AD的诊断有一定的潜在的意义. 相似文献
96.
近年来的研究表明 ,一些小的双链RNA可以高效、特异的阻断体内某些基因致使mRNA降解 ,诱使细胞表现出特定基因缺失的表型 ,称为RNA干扰 (RNAinterference ,RNAi)。由于可以作为代替基因敲除的遗传工具 ,RNAi技术正在改变着功能基因组学 (functionalgenomics)领域的研究步伐。《科学》杂志和美国科学促进会将RNAi技术评选为2 0 0 2年十大重大科学成就之首。1 RNAi及其作用机制1.1 RNAi回顾首次发现双链RNA (doublestrandRNA ,dsR NA)能够导致基因沉默的现象来源于对线虫Caenorhabditiselegans的研究。1995年 ,康乃尔大学的… 相似文献
97.
Deep brain stimulation for Parkinson's disease dissociates mood and motor circuits: a functional MRI case study. 总被引:2,自引:0,他引:2
Taresa Stefurak David Mikulis Helen Mayberg Anthony E Lang Stephanie Hevenor Peter Pahapill Jean Saint-Cyr Andres Lozano 《Movement disorders》2003,18(12):1508-1516
Behavioral disturbances have been reported with subthalamic (STN) deep brain stimulation (DBS) treatment in Parkinson's disease (PD). We report correlative functional imaging (fMRI) of mood and motor responses induced by successive right and left DBS. A 36-year-old woman with medically refractory PD and a history of clinically remitted depression underwent uncomplicated implantation of bilateral STN DBS. High-frequency stimulation of the left electrode improved motor symptoms. Unexpectedly, right DBS alone elicited several reproducible episodes of acute depressive dysphoria. Structural and functional magnetic resonance imaging (fMRI) imaging was carried out with sequential individual electrode stimulation. The electrode on the left was within the inferior STN, whereas the right electrode was marginally superior and lateral to the intended STN target within the Fields of Forel/zona incerta. fMRI image analysis (Analysis of Functional NeuroImages, AFNI) contrasting OFF versus ON stimulation identified significant lateralized blood oxygen level-dependent (BOLD) signal changes with DBS (P < 0.001). Left DBS primarily showed changes in motor regions: increases in premotor and motor cortex, ventrolateral thalamus, putamen, and cerebellum as well as decreases in sensorimotor/supplementary motor cortex. Right DBS showed similar but less extensive change in motor regions. More prominent were the unique increases in superior prefrontal cortex, anterior cingulate (Brodmann's area [BA] 24), anterior thalamus, caudate, and brainstem, and marked widespread decreases in medial prefrontal cortex (BA 9/10). The mood disturbance resolved spontaneously in 4 weeks despite identical stimulation parameters. Transient depressive mood induced by subcortical DBS stimulation was correlated with changes in mesolimbic cortical structures. This case provides new evidence supporting cortical segregation of motor and nonmotor cortico-basal ganglionic systems that may converge in close proximity at the level of the STN and the adjacent white matter tracts (Fields of Forel/zona incerta). 相似文献
98.
Spatial Learning Deficits in Mice with a Targeted Glucocorticoid Receptor Gene Disruption 总被引:5,自引:0,他引:5
Melly S. Oitzl E. Ron de Kloet Marian Joëls Wolfgang Schmid Timothy J. Cole 《The European journal of neuroscience》1997,9(11):2284-2296
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor. 相似文献
99.
100.
功能性矫治器是正畸临床中常用的一种矫治器,作者从口腔正畸学理论基础出发,探讨了功能性矫治器在正畸矫治作用中存在的伦理道德问题,主要有(1)不能正确的诊断、制定周密的矫治计划。(2)操作不规范、不细致、缺乏敬业精神。(3)态度简单,粗曝,缺乏与患者良好的交流。并提出解决方法(1)刻苦学习专业知识,不断提高诊疗水平及个人修养。(2)建立高度的道德责任感,以严谨的作风,规范的操作为病人服务。(3)尊重、善待青少年,建立良好的医患关系。 相似文献