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61.
目的基于功能磁共振成像分析肝豆状核变性(Wilson disease, WD)患者纹状体亚区神经功能损害及其与临床相关分析,探讨其神经心理学症状可能的致病机制。方法收集WD患者29例和健康志愿者30例,进行3.0 T磁共振功能磁共振成像及临床量表测试,采用mICA工具箱的group ICA功能将壳核和尾状核分成8个亚区,做全脑功能连接,提取功能连接异常区域的值与临床量表测试结果做相关性分析。结果与对照组相比,WD患者左侧尾状核中部与全脑未发现功能增强或减弱区域,余感兴趣区与全脑功能连接不同程度减弱。左侧尾状核前部(ROI5)-中扣带回功能连接值与简易智能状态量表(MMSE)值呈显著负相关(r=-0.47,P=0.009);右侧尾状核前部(ROI6)-中扣带回功能连接值与MMSE值呈显著负相关(r=-0.46,P=0.011);右侧尾状核中部(ROI8)-右侧岛叶功能连接值与MMSE值呈显著负相关(r=-0.38,P=0.041)。结论右侧尾状核前中部与背外侧前额叶功能连接减弱,双侧壳核前部与丘脑功能连接减弱,可能破坏皮质-纹状体-丘脑回路引起认知功能损害;参与记忆及动作相关认知的突显网络、默认模式网络的通路连接受阻则可能是WD患者认知障碍的神经病理机制。 相似文献
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64.
《The Knee》2021
BackgroundMedial meniscus (MM) translates and extrudes posteriorly during knee flexion in MM posterior root tear (MMPRT) knees, and transtibial pullout repair of MMPRT has been performed to regulate the MM extrusion. This study aimed to calculate each suture translation during knee flexion in transtibial pullout repair of MMPRT, and to investigate the morphologic features of the MM that lead to longer suture translations during knee flexion.MethodsThirty patients with MMPRT who met the operative indication of pullout repair were enrolled and investigated prospectively. Pullout repair was performed by using two simple stitches (outer and inner sutures) and an all-inside suture in the posteromedial part of the MM. Each suture’s translation from 0° to 90° of knee flexion was measured intraoperatively. The MM morphologic features, including MM medial extrusion (MMME) and MM posterior height (MMPH), were measured using preoperative magnetic resonance imaging, and the correlation between these values and each suture translation was evaluated.ResultsThe average outer, inner, and all-inside suture translations were 4.8 mm, 3.9 mm, and 1.3 mm, respectively. Significant correlations were observed between the outer suture translation and MMME, and MMPH (p < 0.001 and <0.01, respectively). The thresholds for preoperative MMME and MMPH for longer outer suture translations (≥6 mm) were 2.1 mm and 5.4 mm, respectively.ConclusionsPreoperative longer MMME and higher MMPH were associated with longer meniscus translations during knee flexion during MMPRT repair. 相似文献
65.
目的评价两种方法学检测糖类抗原242(CA242)结果的可比性,以评估磁微粒化学发光法检测CA242是否能够满足临床的需求。方法根据美国临床和实验室标准协会(CLSI)新指南EP9-A3文件要求,收集2018年1-7月首都医科大学附属北京康复医院和北京大学首钢医院肿瘤患者检测剩余的新鲜血清标本100例,以Fujirebio Diagnostics AB的酶联免疫法为参比方法,安图生物的磁微粒化学发光法为评估方法,对2种方法检测CA242的结果进行方法学比对和偏移评估。选择Passing-Baklok回归方法进行线性拟合,采用Wilcoxon符号秩检验及Spearman相关分析。结果在4.31~295.63 U/ml范围内,2种方法学的CA242检测结果具有较好的相关性(r=0.991,截距0.652)。参比方法和评估方法比较,差异无统计学意义[(53.75±6.69)U/ml比(56.11±6.86)U/ml,t=0.246,P=0.806]。将CA242的医学决定水平25.00 U/ml代入选取的最佳回归模型拟合方程,计算得到的相对偏移3.52%,<1/2TEa±12.5%(TEa为国家卫生健康委临床检验中心室间质量评审允许总误差),满足要求。结论安图生物的磁微粒化学发光法和Fujirebio Diagnostics AB酶联免疫法检测CA242结果具有可比性,满足临床需要。 相似文献
66.
Though cerebrovascular complications of pregnancy remain relatively rare, they represent a potentially devastating event that necessitates prompt identification and treatment. Eighteen percent of strokes occurring in young women are linked to pregnancy. They occur mostly in the third trimester or during the post-partum period. Their biggest risk factors are hypertension, preeclampsia/eclampsia and migraine. Cerebrovascular events occurring during this period may involve specific pathophysiological processes that include embolic phenomena or endothelial dysfunction, but can also have common etiologies that are simply favored by the context of pregnancy. Thus, posterior encephalopathy and vasoconstriction cerebral syndrome are relatively frequently involved in cerebrovascular complications of pregnancy. Other very specific causes like amniotic fluid embolism or postpartum cardiomyopathy can also be responsible for such events. The management of stroke during pregnancy must be multidisciplinary and include a neurovascular expertise. Some conditions can lead to a long-life follow-up and modify the management of a future pregnancy. 相似文献
67.
IntroductionLevodopa-induced dyskinesia is a complication of levodopa therapy and negatively impacts the quality of life of patients. We aimed to elucidate white matter alterations in Parkinson's disease with levodopa-induced dyskinesia using advanced diffusion magnetic resonance imaging techniques.MethodsThe enrolled subjects included 26 clinically confirmed Parkinson's disease patients without levodopa-induced dyskinesia, 25 Parkinson's disease patients with levodopa-induced dyskinesia, and 23 healthy controls. Subjects were imaged using a 3-T magnetic resonance scanner. Diffusion tensor imaging, diffusion kurtosis imaging, and neurite orientation dispersion and density imaging findings were compared between groups with a group-wise whole brain approach and a region-of-interest analysis for each white matter tract. Additionally, logistic regression analysis was used to calculate odds ratios for levodopa-induced dyskinesia.ResultsGroup-wise tract-based spatial statistical analysis revealed significant white matter differences in isotropic diffusion, complexity, or heterogeneity, and neurite density between healthy controls and Parkinson's disease patients without levodopa-induced dyskinesia and between patients with and without levodopa-induced dyskinesia. Region-of-interest analysis revealed similar alterations using a group-wise whole-brain approach in the external capsule, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, and uncinate fasciculus. These tracts had an odds ratio of approximately 2.3 for the presence of levodopa-induced dyskinesia.ConclusionsOur findings suggest that Parkinson's disease with levodopa-induced dyskinesia produces less white matter microstructural disruption, especially in temporal lobe fibers, than Parkinson's disease without levodopa-induced dyskinesia. These fibers has a more than 2-fold odds ratio for the presence of levodopa-induced dyskinesia and might be associated with the pathogenesis of the sequela. 相似文献
68.
《Clinical neurophysiology》2021,132(5):1185-1193
ObjectivePerinatal arterial ischemic stroke (PAIS) is associated with epileptic spasms of West syndrome (WS) and long term Focal epilepsy (FE). The mechanism of epileptogenic network generation causing hypsarrhythmia of WS is unknown. We hypothesized that Modulation index (MI) [strength of phase-amplitude coupling] and Synchronization likelihood (SL) [degree of connectivity] could interrogate the epileptogenic network in hypsarrhythmia of WS secondary to PAIS.MethodsWe analyzed interictal scalp electroencephalography (EEG) in 10 WS and 11 FE patients with unilateral PAIS. MI between gamma (30–70 Hz) and slow waves (3–4 Hz) was calculated to measure phase-amplitude coupling. SL between electrode pairs was analyzed in 9-frequency bands (5-delta, theta, alpha, beta, gamma) to examine inter- and intra-hemispheric connectivity.ResultsMI was higher in affected hemispheres in WS (p = 0.006); no differences observed in FE. Inter-hemispheric SL of 3-delta, theta, alpha, beta, gamma bands was significantly higher in WS (p < 0.001). In WS, modified Z-Score of intra-hemispheric SL values in 3-delta, theta, alpha, beta and gamma in the affected hemispheres were significantly higher than those in the unaffected hemispheres (p < 0.001) as well as 0.5–4 Hz (p = 0.004).ConclusionsThe significantly higher modulation in affected hemisphere and stronger inter- and intra-hemispheric connectivity generate hypsarrhythmia of WS secondary to PAIS.SignificanceEpileptogenic cortical-subcortical transcallosal networks from affected hemisphere post-PAIS provokes infantile spasms. 相似文献
69.
目的研究螺旋桨采集技术扩散加权成像(PROPELLER DUO DWI)+核磁共振成像(MRI)诊断直肠癌术前T分期的应用价值。方法选取我院2018年6月至2020年6月直肠癌患者65例,均进行MRI及DWI扫描检查,以病理学诊断结果为“金标准”。比较常规MRI与常规MRI+DWI诊断直肠癌T分期的结果及准确率。结果65例直肠癌患者常规MRI诊断T1~T2期33例,T3期22例,T4期10例。MRI+PROPELLER DUO DWI诊断T1~T2期37例,T3期21例,T4期7例。MRI+PROPELLER DUO DWI诊断总准确率为92.3%(60/65),高于MRI[80.0%(52/65,P<0.05)]。结论与MRI常规序列比较,PROPELLER DUODWI技术+常规MRI在直肠癌患者术前T分期诊断中准确率更高,有助于临床治疗方案的制定。 相似文献
70.
Keisuke Nagai Keigo Osuga Eiji Kashiwagi Shinya Kosai Hidenari Hongyo Kaishu Tanaka Yusuke Ono Hiroki Higashihara Noriyuki Tomiyama 《Journal of vascular and interventional radiology : JVIR》2021,32(7):1002-1008
PurposeTo investigate and compare venous sac and feeding artery embolization (VFE) with feeding artery embolization (FAE) alone for treatment of pulmonary arteriovenous malformations (PAVMs), based on difference in outcomes in decrease of the size of the draining vein.Materials and MethodsTwenty-six patients (7 male and 19 female; median age [interquartile range], 58 years [46–65 years]) with 42 simple PAVMs treated with coil embolization between August 2005 and December 2018 were retrospectively evaluated. Twenty PAVMs were treated with FAE early in the study period and compared with 22 PAVMs treated with VFE later in the study period. Follow-up computed tomography images obtained 8–20 months after embolotherapy were used for outcome analysis. Data related to patient demographics; follow-up period; baseline diameters of the feeding artery, venous sac, and draining vein; draining vein diameter after treatment; and decrease in the size of the draining vein, including the number reaching a threshold of 70% decrease, were compared between the 2 groups.ResultsThe draining vein decreased in size by a median of 46.4% in the FAE group and 66.3% in the VFE group, and the difference between the 2 groups was statistically significant (P = .009). There were no significant differences in the other parameters.ConclusionsVFE leads to a greater decrease in the size of the draining vein than FAE, suggesting that VFE results in more complete occlusion than FAE for treatment of PAVMs. 相似文献