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排序方式: 共有474条查询结果,搜索用时 15 毫秒
1.
巴金森氏病病人的年龄、起病年龄、病程、运动障碍的严重程度与其智力损害的关系至今仍存有争议。为此用定量的临床评定方法、标准化的韦氏成人智力测验对31名连续收选的特发性巴金森氏病进行了研究。结果发现缓动的严重程度与智力损害明显相关,而震颤严重程度与智力损害呈反相关。病人的年龄、起病年龄、病程及强直的程度与智力损害无明显相关。这些结果提示引起缓动的皮层下脑损害同样可能引起智力损害,而有明显震颤的巴金森氏病可能属于该病的早期或属于智力损害较轻的一种巴金森氏病亚型。 相似文献
2.
Jingxin Tianming Gang Geoffrey Ashley Lei Stephen T.C. 《Computerized medical imaging and graphics》2007,31(8):656-664
The human brain cortex is a highly convoluted sheet. Mapping of the cortical surface into a canonical coordinate space is an important tool for the study of the structure and function of the brain. Here, we present a technique based on least-square conformal mapping with spring energy for the mapping of the cortical surface. This method aims to reduce the metric and area distortion while maintaining the conformal map and computation efficiency. We demonstrate through numerical results that this method effectively controls metric and area distortion, and is computational efficient. This technique is particularly useful for fast visualization of the brain cortex. 相似文献
3.
目的 探讨各红细胞和网织红细胞参数对遗传性球形红细胞增多症(HS)的筛查诊断价值。方法 收集本院2010年1月—2021年12月确诊的HS患者41例,设为HS组,同时收集40例自身免疫性溶血性贫血(AIHA)患者设为AIHA组,50例地中海贫血(THAL)患者设为THAL组,另选取50例健康体检者为正常对照组。运用t检验比较各组各血细胞参数之间的差异,并采用受试者工作特征(ROC)曲线分析各红细胞参数和网织红细胞参数对HS的筛查诊断价值。结果 HS组平均红细胞体积(MCV)、平均网织红细胞体积(MRV)、平均球形红细胞体积(MSCV)明显低于AIHA组,而平均血红蛋白浓度(MCHC)则明显高于AIHA组(均P<0.05)。HS组MCV、MRV、MSCV均低于正常对照组,MCHC、Ret百分率则明显高于正常对照组,差异有统计学意义(均P<0.05)。HS组和THAL组比较,除Hb外,其余参数差异均有统计学意义(P<0.05)。HS组MSCV低于MCV,而THAL组MSCV高于MCV。HS组MSCV-MCV与其他3组比较差异均有统计学意义(P<0.05)。ROC曲线分析发现MCHC诊断HS的最佳截断值为338.5 g/L,其灵敏度、特异性分别为94.6%和73.7%;MRV最佳截断值为97.1 fL,其灵敏度为91.9%,特异性为86.9%,MSCV-MCV最佳截断值为-3.4 fL,其灵敏度、特异性为94.6%、89.4%。MRV联合MCHC、MRV联合MSCV-MCV ROC曲线下面积(AUC)分别为0.978、0.988,均大于MCHC、MRV、MSCV-MCV任一指标的AUC。结论 MCHC、MRV、MSCV、MSCV-MCV等指标对于HS的鉴别诊断具有重要的参考价值。MCHC不是筛查诊断HS的理想指标,MRV和MSCV-MCV具有较高的预测价值,而联合指标筛查诊断价值要优于单一指标 相似文献
4.
Physiological correlates of perceptual learning in monkey V1 and V2 总被引:12,自引:0,他引:12
Performance in visual discrimination tasks improves with practice. Although the psychophysical parameters of these improvements have suggested the involvement of early areas in visual cortex, there has been little direct study of the physiological correlates of such perceptual learning at the level of individual neurons. To examine how neuronal response properties in the early visual system may change with practice, we trained monkeys for more than 6 mo in an orientation discrimination task in which behaviorally relevant stimuli were restricted to a particular retinal location and oriented around a specific orientation. During training the monkeys' discrimination thresholds gradually improved to much better than those of naive monkeys or humans. Although this improvement was specific to the trained orientation, it showed little retinotopic specificity. The receptive field properties of single neurons from regions representing the trained location and a location in the opposite visual hemifield were measured in V1 and V2. In most respects the receptive field properties in the representations of the trained and untrained regions were indistinguishable. However, in the regions of V1 and V2 representing the trained location, there were slightly fewer neurons whose optimal orientation was near the trained orientation. This resulted in a small but significant decrease in the V1 population response to the trained orientation at the trained location. Consequently, the observed neuronal populations did not exhibit any orientation-specific biases sufficient to explain the orientation specificity of the behavioral improvement. Pooling models suggest that the behavioral improvement was accomplished with a task-dependent and orientation-selective pooling of unaltered signals from early visual neurons. These data suggest that, even for training with stimuli suited to the selectivities found in early areas of visual cortex, behavioral improvements can occur in the absence of pronounced changes in the physiology of those areas. 相似文献
5.
新生儿呼吸窘迫综合征肺表面活性物质治疗后肺氧合功能和尿量变化的观察 总被引:4,自引:0,他引:4
目的 探讨新生儿呼吸窘迫综合征 (RDS)予肺表面活性物质 (PS)治疗后的尿量变化及尿量与肺氧合功能的关系。方法 对新生儿重症监护病房 (NICU)行呼吸机治疗的 2 0例RDS患儿予血气监测及每小时尿量和入量监测。结果 观察组 (PS组 )最大尿量峰值出现于生后 6 0h ,与对照组比较有显著性差异 (P <0 0 5 )。尿量 /入量比值PS组于生后 48h即大于 0 8,而对照组的上述比值大于 0 8出现于生后 6 0h。尿量与动脉 /肺泡氧分压比值 (PaO2 /PAO2 )有显著相关性 (r =0 7414,P <0 0 5 )。结论 RDS病程中随着尿量增加肺氧合功能改善 ,予PS治疗后利尿期最大尿量峰值增大 ,出现时间早 ,提示在PS治疗后更应该密切观察尿量变化 ,判断病情的恢复。 相似文献
6.
用数据挖掘技术实现多因素实验设计 总被引:1,自引:0,他引:1
目的本文介绍如何用数据挖掘技术实现同水平和混合水平多因素实验设计的方法,即独立设计;总结和讨论了独立设计的特点。方法以同水平或混合水平多因素析因设计矩阵为母体,不增加任何限定条件,仅考察各实验点对其余实验点的影响,采用“主成分分析、聚类分析和规则归纳”等数据挖掘技术相结合的方法,先将全部实验点快速分类,然后,再进行聚类,可将此矩阵分解成一系列彼此互不重叠的独立设计矩阵。结果不仅发现用数据挖掘技术实现多因素实验设计是可行的,而且,发现了除正交设计、均匀设计以外的一些可用于多因素实验设计的特殊设计。结论独立设计是一类涵盖面很宽的多因素实验设计方法,它不仅集“析因设计、分式析因设计、正交设计、均匀设计”于一身,还包含有突出“中间水平”或“极端水平”的特殊设计。与正交设计和均匀设计相比较,独立设计的适用面更宽、灵活性更大,具有极大的理论研究价值和广阔的实际应用前景。 相似文献
7.
Hu Nan Zhang Jing Wang Jing Wang Pei Wang Jing Qiang Yongqian Li Zicheng Wu Tianming Wang Xing Wang Yahong Li Jiao Liu Xiaoping Zhang Jirong Feng Xiuyuan Ju Bomiao Hao Zhiming Pu Dan Lu Xiaohong Wang Qiang He Lan 《Clinical rheumatology》2022,41(3):819-829
Clinical Rheumatology - Biomarkers of bone and cartilage metabolism were proposed as early diagnosis indicators for knee osteoarthritis (OA), however, which were influenced by disease stage, age,... 相似文献
8.
目的系统评价Vorapaxar治疗动脉粥样硬化疾病的安全性和有效性。方法检索PubMed、Embase、Cochrane Central Register of Controlled Trials、CNKI全文数据库,收集自建库以来至2014年10月公开发表的有关Vorapaxar治疗动脉粥样硬化疾病的随机对照试验(RCT)。采用RevMan5.1软件进行系统评价和Meta分析。结果共纳入5项RCT,Meta分析显示:Vorapaxar组以心源性死亡(CV)、心肌梗死(MI)和卒中为复合终点事件发生率(OR=0.87,95%CI 0.81~0.93,P<0.01)、主要不良心脑血管事件(MACCE)发生率(OR=0.89,95%CI 0.84~0.95,P<0.01)、CV和MI发生率(OR=0.87,95%CI 0.81~0.93,P<0.01)、MI发生率(OR=0.85,95%CI 0.78~0.92,尸<0.01)低于安慰剂组,而出血发生率(OR=1.48,95%CI 1.39~1.57,P<0.01)以及颅内出血发生率(OR=2.36,95%CI 1.40~3.98,P=0.01)高于安慰剂组。结论在治疗动脉粥样硬化疾病时,Vorapaxar虽然在出血发生率和颅内出血发生率上显著高于安慰剂组,但能显著减少CV、MI和卒中为复合终点事件发生率、MACCE发生率、CV和MI发生率及MI发生率。Vorapaxar可成为治疗动脉粥样硬化疾病的新选择。 相似文献
9.
Aim
To investigate the clinical significance of serum α-Klotho and β-Klotho levels in patients with type 2 diabetes mellitus (T2DM) and its associated complications.Methods
Serum α-Klotho and β-Klotho levels were measured using an ELISA kit in 817 individuals, including 127 with T2DM, 106 with diabetic nephropathy, 99 with diabetic retinopathy, 108 with diabetic neuropathy, 102 with diabetic foot disease, 135 with T2DM and more than one complication and 140 healthy controls.Results
Both α-Klotho and β-Klotho levels were significantly decreased in the T2DM group and the groups with associated complications compared with the levels in control group. The differences between the T2DM group and the T2DM with complications groups were not significant, except between the diabetic nephropathy group and the other diabetic complications groups. In addition, α-Klotho and β-Klotho levels were negatively correlated with serum fructosamine and HbA1c but were not associated with serum glucose in the model including all participants. Moreover, decreases in α-Klotho and β-Klotho levels in the high glucose-exposed cell culture model, which was dependent on glucose exposure time, were confirmed.Conclusions
Levels of α-Klotho and β-Klotho were downregulated in patients in the T2DM and complications groups. Our findings indicate that serum Klotho levels were associated with the development of T2DM, and long-term control of blood glucose will be beneficial in ameliorating changes to α-Klotho and β-Klotho levels in patients with T2DM and complications. 相似文献10.
Brain Imaging and Behavior - Functional mechanism of the brain and its relationship with the brain structural substrate have been an interest for multiple disciplines for centuries. Recently, gyri... 相似文献