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《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
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目的:探讨血化瘀方联合针灸治疗对脑梗后遗症患者脑血管血液流变动力学及神经功能的影响。方法:选取2016年1月至2017年1月沈阳市第二中医医院收治脑梗后遗症患者120例作为研究对象,对照组61例患者接受针灸治疗;观察组59例患者接受活血化瘀方联合针灸治疗。2组连续治疗30 d。比较2组患者脑血流流变学指标、神经功能评分、中医证候积分、临床疗效。结果:治疗前2组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量比较,差异无统计学意义(P 0. 05)。治疗后观察组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量大于对照组(P 0. 05)。治疗前2组患者NIHSS评分、MMSE评分比较,差异无统计学意义(P 0. 05)。治疗后观察组患者NIHSS评分显著低于对照组,MMSE评分高于对照组(P 0. 05)。治疗前2组患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分比较,差异无统计学意义(P 0. 05)。治疗后研究患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分显著低于对照组(P 0. 05)。2组患者临床疗效比较,差异有统计学意义(Z=-5. 626,P=0. 000)。结论:活血化瘀方联合针灸能改善脑梗后遗症患者脑血管血液流变动力学指标,保护神经功能。 相似文献
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Emma J. Kilford Iroise Dumontheil Nicholas W. Wood Sarah-Jayne Blakemore 《Social cognitive and affective neuroscience》2015,10(6):777-782
The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val158Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function. 相似文献
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Over the past 20 years there has been a growing interest in the neural underpinnings of cost/benefit decision-making. Recent studies with animal models have made considerable advances in our understanding of how different prefrontal, striatal, limbic and monoaminergic circuits interact to promote efficient risk/reward decision-making, and how dysfunction in these circuits underlies aberrant decision-making observed in numerous psychiatric disorders. This review will highlight recent findings from studies exploring these questions using a variety of behavioral assays, as well as molecular, pharmacological, neurophysiological, and translational approaches. We begin with a discussion of how neural systems related to decision subcomponents may interact to generate more complex decisions involving risk and uncertainty. This is followed by an overview of interactions between prefrontal-amygdala-dopamine and habenular circuits in regulating choice between certain and uncertain rewards and how different modes of dopamine transmission may contribute to these processes. These data will be compared with results from other studies investigating the contribution of some of these systems to guiding decision-making related to rewards vs. punishment. Lastly, we provide a brief summary of impairments in risk-related decision-making associated with psychiatric disorders, highlighting recent translational studies in laboratory animals. 相似文献
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目的探讨前列地尔联合长春西汀治疗急性脑梗死的疗效。方法选取2015年3-12月在我科接受治疗的90例急性脑梗死患者,随机分为治疗组(45例)和对照组(45例)。两组患者均给予抗血小板、降血脂等常规对症治疗,11 d为1个疗程。对照组给予长春西汀静脉输液治疗,治疗组在对照组基础上加以前列地尔治疗。比较两组临床治疗效果,治疗前后神经功能恢复情况、日常生活能力恢复情况、并发症发生率及安全性。结果治疗组总有效率为93.3%,对照组为71.1%,治疗组明显高于对照组,差异有统计学意义(P<0.05)。两组患者用药11 d后,神经功能缺损评分均高于治疗前,且治疗组明显高于对照组,差异均有统计学意义(P<0.05)。治疗组患者用药11d及90 d后日常生活能力恢复情况优于对照组,差异有统计学意义(P<0.05)。两组均无严重药物不良反应。结论前列地尔联合长春西汀治疗急性脑梗死疗效显著,值得临床推广应用。 相似文献
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目的 研究凉血通瘀方对高血压大鼠急性脑出血模型脑组织miRNA表达的影响,对差异表达的miRNA靶基因进行分析,探索凉血通瘀方可能的药效机制。方法 将自发性高血压大鼠随机分成对照组(B)和实验组(C)。适应性饲养一周后,C组灌胃凉血通瘀方,B组灌胃等体积生理盐水,连续5天,每天1次。构建脑出血模型后收集脑组织,借助全转录组测序技术获得miRNA表达量,与miRBase数据库比对获取已知miRNA,使用miRDeep2预测新miRNA。差异分析软件为DESeq2,筛选阈值为|log2FC| ≥1 并且P <0.05。对显著差异表达的miRNA进行靶基因预测,对靶基因进行GO功能、KEGG通路富集和PPI网络分析。结果 实验组和对照组对比,共发现21个显著差异表达的miRNA,上调有9个,下调有12个,共预测得到1243个有统计学意义的靶基因。GO富集分析发现,生物过程中突触囊泡分泌的调节、神经递质分泌的调节和神经递质运输的调节占前三位,神经元投射终点、全膜、质膜区域和细胞投射则是主要的细胞成分。分子功能分别为小GTPase绑定、底物特异性跨膜转运蛋白活性和离子跨膜转运体活性。通路分析结果显示,靶基因在癌证通路、pI3K-Akt信号通路、人类乳头瘤病毒感染、神经活性配体-受体相互作用和MAPK通路等分布广泛。采用STRING网站和Cytoscape软件,根据MCC算法筛选出ADRA2C、CASR、CCL28、CCR1、DRD2、GNAT3、GRM2、DYNC1LI1、GABBR1、GNAI1等核心靶基因。结论 凉血通瘀方对脑出血急性期鼠脑组织内miRNA的表达有重要影响;显著差异表达miRNAs可能通过靶向核心基因调控凉血通瘀方干预急性脑出血的病理过程及预后。 相似文献
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《Diagnostic Histopathology》2019,25(9):360-366
Sudden death in childhood and adolescence is fortunately rare. However, when it occurs, it can have a devastating effect on the family. Therefore, these cases should be thoroughly investigated, including a complete post mortem examination by a specialist in paediatric pathology. The aim is to identify the cause of death, and potentially prevent future deaths. This review will provide an overview of the epidemiology of sudden death in childhood and adolescence and will outline the wide range of causes of death identified. Certain aspects of the paediatric post mortem examination will be discussed, and will finish with a section on deaths in children with chronic medical conditions. 相似文献
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Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway. 相似文献