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11.
Movement-related potentials were recorded preceding self-paced voluntary movements in patients with Parkinson's disease and in healthy subjects of the same age group. We compared the Readiness Potential preceding joystick movements in a fixed direction and preceding joystick movements in freely selected directions. In normal subjects the Readiness Potential amplitude was higher preceding freely selected movements than preceding movements in a fixed direction. The Readiness Potential in Parkinson patients failed to be modified by the different modes of movement selection. The modulation of the Readiness Potential by different ways of preparing for movement might be due to the supplementary motor area (SMA) being more strongly engaged by tasks requiring internal control of movements than by tasks that are externally structured. The results suggest that this task-dependent variation of SMA activity is reduced in Parkinson's disease. A failing capacity to adapt SMA activity to different task demands has previously been suggested by evidence from positron emission tomography studies using similar tasks.  相似文献   
12.
Summary Thirty-three cat brains with injections of horseradish peroxidase in various regions of the cerebral cortex were screened for afferent projections from the ventral tegmental area, the locus ceruleus, and the parabrachial nuclei. All three structures were found to project to rather divergent parts of the cortex, including regions in the posterior half of the hemisphere. These results, especially for the ventral tegmental area and, to a lesser degree, for the parabrachial neurons, disagree with most of the target loci of established cortical afferents in the rat. Though our results might be attributed to species differences in the cortical innervation of brain stem structures, we prefer explanations which emphasize different densities in the distribution of brain stem afferents to the cortex, and/or which suggest different cortical targets of catecholaminergic and noncatecholaminergic neurons.Supported in part by grant Ma 795 from the Deutsche Forschungsgemeinschaft (DFG)  相似文献   
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14.
北京农村居民健康状况及卫生服务需求调查   总被引:17,自引:5,他引:12  
目的了解北京农村居民健康状况及卫生服务需求特点。方法从昌平区、顺义区、大兴区、房山区随机抽取25~64岁农民1605人进行统一问卷调查。结果农民高血压自报患病率为22.4%,超重和肥胖率为56.1%;现在吸烟率为34.4%,缺乏运动率为41.6%;家庭主要经济支出为学生上学(35.3%),建房(25.4%)和疾病(21.2%);54.9%家庭医疗费用支出占总收入的10%以上;最关心的健康问题主要是慢性疾病防治(70.2%);最希望获得的健康知识是慢性病预防知识(72%);希望获得健康知识的途径是广播和电视(81%);家庭最希望获得的医疗保健服务是方便看病和获得药物(73.8%)。结论慢性病给农民带来沉重负担,并成为农民关心的主要健康问题。  相似文献   
15.
活性炭纤维在地方性氟中毒方面的应用展望   总被引:1,自引:0,他引:1  
曹守仁 《卫生研究》1994,23(2):77-79
介绍了活性炭纤维(ACFs)的制造,特性及其应用。它具有优异的结耕与性能特征。含碳量高,比表面积大,微孔丰富,从而吸附力强,而且活性炭纤维还可制成纱、布、毡等形状,它可用于去除燃煤氟中毒区室内空气中氟化氢、二氧化硫、氧化氮、氨等污染物,利用它的高吸附性能还可较好的去除饮水中的氟化物及其他有害物质。活性炭纤维是一种新型高效吸附材料。在氟中毒防治方面有广阔的前途。  相似文献   
16.
Summary. In recent years the continuity equation has been established as a valuable non-invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub-valvular stenosis in the left ventricle-outflow tract, because the area of the outflow trace is not circular in those cases. The authors have tested the value of a non-invasive variant of the Gorlin formula, as an alternative method of identifying severe aortic stenosis. They examined 32 consecutive patients with aortic stenosis with both methods. Seventeen patients had severe stenosis (valve area^0–7 cm2), calculated by the continuity equation. The other 15 patients had moderate stenosis (valve area 0–7–1–0 cm2). Using the non-invasive variant of the Gorlin formula, the authors were able to identify 16 of the 17 cases with severe stenosis, thus showing that the method is useful for identifying severe aortic stenosis. (P<0–001 by x2-test).  相似文献   
17.
对AF系统整复压缩爆裂骨折椎体高度及椎管横截面的观测   总被引:4,自引:3,他引:1  
目的 :量化评价AF系统恢复胸腰段压缩爆裂椎体高度椎管截面积的效果。方法 :测量AF系统治疗的 72例胸腰段压缩爆裂骨折术前后影像。统计椎体前后缘高度、Cobb角、椎管截面积资料。结果 :术后伤椎前缘高度恢复至 ( 96.5± 2 .3 ) %后缘高度恢复至 ( 98.2± 0 .9) % ,Cobb角恢复至 ( 5 .4± 1.5 )° ,椎管截面积恢复至 ( 97.2± 2 .1% ) ,各项指标与术前比较有非常显著性差异 (P <0 .0 0 1)。术后随访 0 .5~ 3 .5年 ,神经功能按Frankel评定 :60例提高 1~ 3级。结论 :AF系统能恢复或基本恢复胸腰段压缩爆裂骨折椎体的前后缘高度、Cobb角、椎管容积 ,为脊髓神经功能的恢复提供一个良好的环境。是治疗脊柱胸腰段压缩爆裂骨折较好的内固定器。  相似文献   
18.
立体定向技术治疗癫痫性精神病的体会   总被引:6,自引:3,他引:3  
目的:探讨多靶点组合对癫痫性精神病的治疗效果。方法:采用立体定向技术,运用多元化定位和多靶点组合,射频热凝脑内核(团)治疗癫痫性精神病53例。术前、术后均进行总疗效评定量表(GAS)和癫痫的国际疗效评价进行疗效评定。结果:53例中显效37例,进步16例。结论:双侧胼胝体、杏仁核、内侧隔区及单侧红核前区多靶点组合治疗,对癫痫性精神病的治疗有明显作用。  相似文献   
19.
To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension.  相似文献   
20.
(1)目的 探讨鼻内窥镜下Nd:YAG激光治疗变应性鼻炎的方法。(2)方法 应用鼻内镜下Nd:YAG激光凝固中务甲前1/3端治疗变应性鼻炎126例。(3) 结果 随访1年,显效109例(86.5%),有效13例(10.3%),无效4例(3.2%),总有效率96.8%。(4)结论 鼻内镜下Nd:YAG激光凝固中鼻甲前1.3端治疗变应性鼻炎,具有视野清楚,操作简便,疗效好等优点,值得临床应用。  相似文献   
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