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91.
目的:探讨介入栓塞术治疗头颈部肿瘤放射治疗后大出血的临床应用价值。方法 :对 6例头颈部肿瘤放射治疗后大出血患者采用数字减影血管造影技术 (DSA)对颈外动脉分支进行介入栓塞治疗。结果:6例病例在DSA下均显示出血血管 ,栓塞后出血停止 ,临床效果满意。 结论:DSA下介入栓塞止血对头颈部肿瘤放射治疗后大出血是一种较为理想的治疗手段 ,操作简便、安全。  相似文献   
92.
The purpose of this study was to examine motor learning and retention given extensive practice in two fundamentally different movement sequences. One sequence was a memory-driven task (performing a series of whole body positions from memory) and the other a context-driven task (buttoning). Practice took place over 3 weeks, with performance measured weekly; retention was measured weekly for 3 weeks after practice. There were 7 people with Parkinson's disease (PD) and 7 age-matched neurologically healthy people who participated in this study. Both groups improved performance on both tasks with practice, with the majority of the change for the PD group occurring between 1 and 2 weeks of practice. Although those with PD did not necessarily perform as well as age-matched controls, they learned both sequences in a manner similar to age-matched controls, and exhibited retention across the 3-week retention interval. If people with PD are given sufficient practice they can learn and retain both memory-based and context-driven movement sequences as well as age-matched controls. The results provide support for maintaining physical activity and for intervention through movement therapy.  相似文献   
93.
目的探讨影响闭合复位空心钉治疗中老年股骨颈骨折后股骨头坏死的相关因素及其多元关系。方法对1999年5月~2004年5月间收治的300例中老年股骨颈骨折患者进行回顾性分析,所有患者均行闭合复位空心钉固定。对随访资料完整的99例患者资料运用SPSS10.0软件进行统计学分析,即对其年龄、性别、骨折类型、复位时间、复位质量、完全负重时间、内固定是否取出及术前是否行牵引等因素进行多因素分析。结果99例患者获平均24.5个月(8~60个月)随访。15例出现股骨头坏死,坏死率为15.2%,发生坏死的时间为术后8~50个月。由复位质量、术前牵引、年龄及年龄×取出内固定构成的多因素组对股骨颈骨折后股骨头坏死的影响最显著。结论闭合复位质量对股骨颈骨折预后的影响程度极大;不良位置的术前牵引可能加重股骨头坏死;年龄在多因素共同影响中的相对危险度不大;Garden分型是判断股骨颈骨折后股骨头坏死的一项重要指标,与骨折复位质量具有相关性,但其并非是多因素共同影响下造成股骨头坏死的危险因素。  相似文献   
94.
The results of many anatomical, physiological, and pharmacological studies suggest that substance P-containing neurons of the striatum project to the substantia nigra, and that substance P influences the activity of dopaminergic nigrostriatal neurons. The purpose of the present ultrastructural study was to employ dual immunocytochemical labeling to determine the morphological basis for the observed actions of substance P on nigral dopaminergic neurons. Substance P-like and tyrosine hydroxylase-like immunoreactivities were localized simultaneously at the ultrastructural level in the substantia nigra of the rat. A double label method was utilized which relied on a combination of the peroxidase-antiperoxidase method (Sternberger, 1979) for substance P, and immunogold or silver enhanced immunogold labeling for tyrosine hydroxylase. The present results indicate that tyrosine hydroxylase immunoreactive (THLI) dendrites in the substantia nigra receive synaptic input from terminals exhibiting substance P-like immunoreactivity. These findings support the idea that substance P is a major neurotransmitter in the striatonigral loop, and suggest that striatal substance P neurons act directly upon nigral dopaminergic cells.  相似文献   
95.
桡骨颈骨折经皮撬拨复位的远期疗效   总被引:1,自引:0,他引:1  
用经皮撬拨复位治疗桡骨颈骨折56例,其中复位良好46例,较好6例和不良4例;经3年7个月平均随访,复位良好和较好的44例中,后期疗效良好32例,较好11例和一般1例。骨折解剖复位、撬拨复位的手术损伤轻和石膏固定时间较短是后期疗效满意的关键。成人桡骨颈骨折伴肘内侧副韧带严重损伤比儿童多见,但儿童桡骨颈骨折严重倾斜移位和完全移位比成人多见,后期疗效更满意。  相似文献   
96.
Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6–12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Martrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nippostrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determinded by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart ≥ thymus ≥ Nb-MLN ≥ spleen ≥ MLN ≥ SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93,80, and 77% inhibition at 24 hr; 86,70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF. These neurotrophic/tropic factors are produced during the reactive lymphoid hyperplasia that forms part of the inflammatory response against the nematode, N. brasiliensis. This suggests the possibility that cytokines produced by lymphocytes or other inflammatory cells may stimulate sympathetic neurite outgrowth in vivo. © 1994 Wiley-Liss, Inc.  相似文献   
97.
颈部神经鞘瘤34例临床分析   总被引:1,自引:0,他引:1  
对34例颈部神经鞘瘤进行了临床分析,均以颈部无痛性包块为主诉。16例压迫肿瘤可引起肢端麻木、放射性疼痛或压气、呛咳等症状,10例肿块穿刺抽出囊液,82.2%来诊时诊断不清楚,需与颈部其他肿瘤相鉴别,B超对诊断有帮助。本组手术行肿瘤核除术13例,肿瘤切除术19例,取病理2例。应争取做保留神经功能的肿瘤核除术。  相似文献   
98.
The present investigation introduces an in vitro model to study macrophage properties during demyelination. Rat dorsal root ganglia (DRG) were cultured for obtaining myelinated peripheral nerve fibers. These cultures were exposed to non-resident macrophages. In untreated control cultures, there was no indication of myelin removal by the added macrophages. DRG were exposed to enzymatically generated oxygen radicals using the xanthin/xanthin oxidase or the glucose/glucose oxidase system. Assessment of Schwann cell viability and ultrastructural morphology revealed different patterns of cell cytotoxicity and morphological changes in different experiments. High concentrations caused complete tissue necrosis of the DRG, while low concentrations did not affect either cell viability or ultrastructural morphology. Under intermediate experimental conditions, oxygen radicals caused non-lethal Schwann cell damage leading to Schwann cell retraction and myelin sheath rejection. Myelin lamellae were disrupted and decompacted. These changes were followed by a selective macrophage attack on myelin sheats, resulting in demyelination. Axons, Schwann cells and sensory ganglion cells survived this attack. The specificity of the oxygen radical effects was tested in experiments using the oxygen radical scavengers catalase and superoxide dismutase. Catalase prevented the described effects on cell morphology and subsequently blocked demyelination by non-resident macrophages.Supported by a grant from the Deutsche Forschungsgemeinschaft (DFG) (Br 1274/1-1)  相似文献   
99.
The technique of quantitative autoradiography was used to examine the effects of Huntington's disease (HD) and schizophrenia on the organization of striatal dopamine (DA) D1 and D2 receptors. Whereas the striatum of HD cases showed a reduction in the density of D1 ([3H]SCH 23390) and D2 ([3H]spiroperidol) receptors, the patterning of D2 receptor loss did not match that of the D1 receptor loss. The HD loss of D1 D1 receptors (65%) is far greater than the loss of D2 receptors (28%). Whereas there was a dorsal-ventral gradient of effect on both receptor subtypes, the effects of HD on D2 receptors in the ventral putamen (PUT) and nucleus accumben septi (NAS) were minimal. Similarly, muscarinic M1 and M2 receptors demonstrate different patterns of alteration in HD. The M2 subtype, labeled with [3H]N-methylscopolamine (in the presence of excess pirenzepine to occlude M1 sites), was depleted far more than the M1 receptor subtype, labeled with [3H]pirenzepine. Although the effects of HD on [3H]mazindol labeling of DA terminals were more heterogeneous, there appeared to be a relative preservation of this afferent input to the striatum of the HD cases. In the schizophrenic cases, our autoradiographic studies confirm previous reports of an elevation of D2 receptor density in the striata of many schizophrenics. This increase was evident even though two of the three cases were known to have not been treated with neuroleptics, and the third case may also have been drug naive. However, the increase was far greater in the NAS (164%) and ventral PUT (173%) than more dorsally in the striatum (68%). The density of D1 receptors and DA terminals labeled with [3H]mazindol in the striatum of schizophrenics was not significantly different from that of control cases. Thus in both HD and schizophrenia, the ratio of D2/D1 receptors is altered in favor of the D2 population, particularly in the NAS.  相似文献   
100.
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