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51.
目的:基于原发肿瘤及淋巴结CT特征建立评分模型预测食管鳞癌患者喉返神经旁淋巴结(RLN-LN)转移风险。方法:回顾性收集2014年1月至2019年12月于北京大学肿瘤医院行食管癌根治术并清扫RLN-LN的92例食管鳞癌患者。根据术后淋巴结病理结果分为RLN-LN转移组(n=37)和非转移组(n=55)。评估术前CT图像,记录食管癌患者年龄、性别、分化程度、肿瘤位置、肿瘤大小(肿瘤长度、肿瘤厚度、厚度/长度)、RLN-LN大小(淋巴结短径、长径、短径/多平面重建(MPR)最长径]。采用多元logistic回归筛选独立预测因子并建立评分模型,采用ROC曲线评估评分模型及独立预测因子诊断RLN-LN转移的效能,采用Z检验比较曲线下面积(AUC)的差异。应用Hosmer-Lemeshow检验和校准曲线评估模型拟合度。结果:肿瘤位置、肿瘤长度、RLN-LN短径、短径/MPR最长径是RLN-LN转移的独立预测因子,其诊断RLN-LN转移的AUC分别为0.586、0.705、0.831、0.777。基于以上4个CT特征建立评分模型,评分模型诊断RLN-LN转移的AUC为0.903(95%CI 0.846~0.959),优于各单一CT特征(Z=5.812,P<0.001;Z=2.161,P=0.030;Z=2.929,P=0.003;Z=4.052,P<0.001)。拟合优度Hosmer-Lemeshow检验结果显示P=0.555,校准曲线提示评分模型预测RLN-LN转移风险与实际转移风险之间具有良好的一致性。结论:基于CT图像的评分模型有助于食管鳞癌RLN-LN转移状态危险分层。  相似文献   
52.
《Clinical neurophysiology》2021,132(10):2431-2439
ObjectiveThe purpose of this investigation was to better understand the effects of concussions on the ability to selectively up or down-regulate incoming somatosensory information based on relevance.MethodsMedian nerve somatosensory-evoked potentials (SEPs) were elicited from electrical stimulation and recorded from scalp electrodes while participants completed tasks that altered the relevance of specific somatosensory information being conveyed along the stimulated nerve.ResultsWithin the control group, SEP amplitudes for task-relevant somatosensory information were significantly greater than for non-relevant somatosensory information at the earliest cortical processing potentials (N20-P27). Alternatively, the concussion history group showed similar SEP amplitudes for all conditions at early processing potentials, however a pattern similar to controls emerged later in the processing stream (P100) where both movement-related gating and facilitation of task-relevant information were present.ConclusionsPreviously concussed participants demonstrated impairments in the ability to up-regulate relevant somatosensory information at early processing stages. These effects appear to be chronic, as this pattern was observed on average several years after participants’ most recent concussion.SignificanceGiven the role of the prefrontal cortex in relevancy-based facilitation during movement-related gating, these findings lend support to the notion that this brain area may be particularly vulnerable to concussive forces.  相似文献   
53.
孤独症谱系障碍是一种患病率日益增长的神经发育综合征,可出现多种行为障碍。近年来,重复经颅磁刺激在孤独症谱系障碍治疗中取得了一些研究成果,但关于刺激参数选择、安全性及可行性评估方面仍存在一定争议。本文就其关于诱导长时程增强/抑制、调节皮质抑制的治疗机制、低频和高频经颅磁刺激的临床应用及目前涉及的安全性、道德伦理问题等局限性进行综述,从而为今后的研究与临床应用提供一定的参考依据。  相似文献   
54.
目的探讨枕下三角境界及内容物的检查方法与超声解剖学特点,为临床检查枕下三角提供超声影像学资料。方法对100例健康成年人枕下区进行超声检查,描述枕下三角境界的超声判定及解剖关系;阐述枕大神经的走行特点,测量头下斜肌表面枕大神经的横截面积;记录椎动脉V3段管腔内径(D)、收缩期峰值流速(PSV)、舒张期末流速(EDV)、阻力指数(PI)。结果 (1)寰椎后结节左侧约1 cm处纵切声像图显示寰椎后弓呈"短弧形"强回声,其后上方为头后大直肌、后下方为头下斜肌,三者分别构成枕下三角的底、内上界和外下界。(2)寰椎侧块处纵切声像图显示侧块为"平台样"强回声结构,其后方为椎动脉V3段、下方紧接寰椎后弓;后弓后方为头下斜肌、后上方为头上斜肌,头上斜肌构成三角的外上界,后弓与椎动脉V3段之间为枕下神经所在区域。(3)枕大神经长轴声像图显示神经从头下斜肌下缘发出后向内上走行于头下斜肌及头后大直肌与头半棘肌之间;不同性别头下斜肌表面枕大神经横截面积两侧比较,差异均无统计学意义(P>0.05)。(4)寰椎侧块处横切声像图显示椎动脉V3段呈"倒U形"绕侧块进入枕骨大孔,排除发育不良者,测V3段D为(3.52±0.39)mm、PSV及EDV分别为(43.33±9.05)、(21.87±5.86)cm/s、RI为(0.49±0.11)。结论超声是检查枕下三角及其内容物的理想方法。  相似文献   
55.
目的观察腰椎旁神经阻滞联合全凭静脉全身麻醉对髋关节置换术患者血流动力学、应激反应、术后苏醒的影响。方法选取2018年1月—2019年8月我院收治的行髋关节置换术患者115例,根据手术麻醉方法的不同分为观察组60例和对照组55例,观察组予腰椎旁神经阻滞联合全凭静脉全身麻醉,对照组仅予全凭静脉全身麻醉。比较两组麻醉前(T0)、麻醉后10 min(T1)、麻醉后30 min(T2)、术毕(T3)时平均动脉压、心率、去甲肾上腺素及肾上腺素水平变化,术后清醒镇静效果和苏醒时间,以及两组手术期间不良反应发生情况。结果观察组T1、T2、T3时平均动脉压、心率与T0时比较虽略有升高,但差异无统计学意义(P>0.05);对照组T1、T2、T3时平均动脉压、心率与T0时比较均升高,且以T2时平均动脉压、心率最高,T3时又回落至T1时水平,差异有统计学意义(P<0.05)。T1、T2、T3时观察组平均动脉压、心率均低于对照组(P<0.05)。T1、T2、T3时两组去甲肾上腺素、肾上腺素均较T0时升高,且观察组相同时间点去甲肾上腺素、肾上腺素水平低于对照组,差异均有统计学意义(P<0.05或P<0.01)。观察组术后唤醒时警觉/镇静评分低于对照组,苏醒时间明显短于对照组,差异均有统计学意义(P<0.05)。两组手术期间总不良反应发生率比较差异无统计学意义(P>0.05)。结论腰椎旁神经阻滞联合全凭静脉全身麻醉用于髋关节置换术可有效防止患者血流动力学指标的波动,减轻手术应激反应程度,术后苏醒快,术后苏醒质量佳,且未增加手术期间不良反应的发生。  相似文献   
56.
目的 探讨超声引导下连续椎旁神经阻滞(PVNB)对老年食道癌开胸手术患者术后镇痛、应激及炎性因子水平的影响。方法 选取我院拟实施全麻下开胸手术的90例食道癌开胸手术患者作为研究对象,其中45例患者术前采用超声引导下PVNB麻醉复合全身麻醉(PVNB组)、对照组45例患者采用全身麻醉;两组患者术后均采用静脉自控镇痛(对照组);对比两组患者术后2h、6h、24h及48h静息状态、咳嗽状态下的视觉模拟疼痛评分(VAS),术后镇痛药物用量及镇痛药物不良反应发生情况,术前及术后24h血清去甲肾上腺素(NE)、肾上腺素(E)、皮质醇(Cor)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)差异及术后肺部感染发生情况。结果 PVNB组患者和对照组在术后2h~术后48h的静息VAS评分及咳嗽VAS评分组间比较,差异具有统计学意义(P<0.05),PVNB组术后2h、6h及24h静息VAS评分及咳嗽VAS评分均高于对照组(P>0.05)。PVNB组患者术后的镇痛泵按压次数、舒芬太尼用量均低于对照组(P<0.05),PVNB组患者术后的镇痛泵按压次数、舒芬太尼用量均低于对照组(P<0.05),术前两组患者的血清NE、E、Cor水平差异无统计学意义(P>0.05);术后两24h两组患者血清NE、E、Cor水平均较术前增高(P>0.05),术后24h PVNB组的血清NE、E、Cor水平低于对照组(P<0.05),术前两组患者的血清IL-6、TNF-α水平差异无统计学意义(P>0.05);术后24h两组患者血清IL-6、IL-10、TNF-α水平均较术前增高(P<0.05),PVNB组的血清IL-6、TNF-α水平低于对照组(P<0.05),PVNB组术后发生肺部感染2例,发生率为4.4%,对照组术后发生肺部感染6例,发生率为13.3%,PVNB组术后肺部感染发生率低于对照组(P<0.05)。结论 超声引导下PVNB能够改善老年食道癌开胸患者术后镇痛效果,减轻手术创伤所致的应激反应,较少患者术后肺部感染的发生。  相似文献   
57.
58.
BackgroundRhythmic Auditory Stimulation (RAS) involves synchronizing footsteps to music or a metronome to improve gait speed and stability in patients with neurological disorders, such as Parkinson’s disease. However, responses to RAS vary across individuals, perhaps because of differences in enjoyment of the music or in musical abilities.Research questionIntuitively, musical enjoyment may influence gait responses to RAS, but enjoyment has not been systematically manipulated nor the effects empirically assessed. In addition, differences in beat perception ability are likely to influence gait responses to music, particularly when synchronizing to the beat. Therefore, we asked: how does music enjoyment alter gait, and do gait parameters differ between individuals with good versus poor beat perception ability, specifically when instructed to ‘walk freely’ versus ‘synchronize to the beat’?MethodYoung adults and older adults walked on a pressure sensor walkway in silence and to music that they had rated as either high or low in enjoyment, as well as a metronome. All stimuli were presented at 15 % faster than baseline cadence. Participants either walked freely to the music or synchronized to the beat.ResultsMusic enjoyment had no significant effects on gait in either younger or older adults. Compared to baseline, younger adults walked faster (by taking longer strides) to music than the metronome, whereas older adults walked faster (by taking more steps per minute) to the metronome than music. When instructed to synchronize vs. walk freely, young adults walked faster, but older adults walked slower. Finally, regardless of instruction type, young adults with poor beat perception took shorter and slower strides to the music, whereas older adults with poor beat perception took slower strides to the music.SignificanceBeat perception ability, instruction type, and age affect gait more than music enjoyment does, and thus should be considered when optimizing RAS outcomes.  相似文献   
59.
《Neuromodulation》2021,24(8):1317-1326
ObjectivesHow spinal cord stimulation (SCS) in its different modes suppresses pain is poorly understood. Mechanisms of action may reside locally in the spinal cord, but also involve a larger network including subcortical and cortical brain structures. Tonic, burst, and high-frequency modes of SCS can, in principle, entrain distinct temporal activity patterns in this network, but finally have to yield specific effects on pain suppression. Here, we employ high-density electroencephalography (EEG) and recently developed spatial filtering techniques to reduce SCS artifacts and to enhance EEG signals specifically related to neuromodulation by SCS.Materials and MethodsWe recorded high-density resting-state EEGs in patients suffering from pain of various etiologies under different modes of SCS. We established a pipeline for the robust spectral analysis of oscillatory brain activity during SCS, which includes spatial filtering for attenuation of pulse artifacts and enhancement of brain activity potentially modulated by SCS.ResultsIn sensor regions responsive to SCS, neuromodulation strongly reduced activity in the theta and low alpha range (6–10 Hz) in all SCS modes. Results were consistent in all patients, and in accordance with thalamocortical dysrhythmia hypothesis of pain. Only in the tonic mode showing paresthesia as side effect, SCS also consistently and strongly reduced high-gamma activity (>84 Hz).ConclusionsEEG spectral analysis combined with spatial filtering allows for a spatially and temporally specific assessment of SCS-related, neuromodulatory EEG activity, and may help to disentangle therapeutic and side effects of SCS.  相似文献   
60.
We report two cases of granuloma that occurred around an implantable pulse generator (IPG) for deep brain stimulation. Both cases showed no signs of infection and disappeared after moving the IPG and removing the granulation. If a noninfectious mass is formed, the relocation of IPG may improve it.  相似文献   
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