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排序方式: 共有5726条查询结果,搜索用时 15 毫秒
1.
目的 探讨高血压性基底节区出血引流术后发生颅内感染的危险因素。方法 回顾性分析2015年5月~2020年4月引流术治疗的481例高血压性基底节区出血的临床资料。结果 481例中,术后发生颅内感染28例,发生率为5.8%;治愈24例,治愈率85.7%。28例颅内感染中,培养出致病菌26例,其中革兰阳性菌16例(61.5%),革兰阴性菌10例。多因素logistic回归分析显示年龄≥60岁、白蛋白水平<35 g/L、术前GCS评分≤8分、置管时间>3 d、鞘内注射>6次、引流管口漏是术后颅内感染的独立危险因素(P<0.05)。结论 高血压性脑出血引流术后颅内感染是受多种原因影响的,预防为主,防治结合,以降低术后颅内感染发生率及病死率。 相似文献
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目的 总结一种简单实施、有效的、标准的经冠状缝-额中回入路神经内镜手术治疗高血压性基底节区出血的标准化流程。方法 回顾性分析2019年4月至2021年4月按统一标准实施的经冠状缝-额中回入路神经内镜手术治疗的48例高血压性基底节区出血的临床资料。术中未使用神经导航及3D-slicer等软件辅助定位。结果 术后24 h内复查头CT显示残余血肿量中位数为2.4(1.1~3.9)ml;血肿清除率中位数为94.0%(90.0%~98.0%)。无术后再出血。出院时GCS评分中位数为13(11~14)分。术后随访6~30个月(中位数15个月),mRS评分0~2分35例,3~4分10例,5~6分3例。结论 神经内镜下经冠状缝-额中回入路手术治疗高血压性基底节区出血是一种简单易行的手术方式,无需神经导航及3D-slicer等软件辅助定位,可以取得良好的手术效果。 相似文献
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Yicheng Chen Ozan Genc Clare B. Poynton Suchandrima Banerjee Christopher P. Hess Janine M. Lupo 《NMR in biomedicine》2022,35(5):e4666
Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength. 相似文献
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《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(4):529-532
IntroductionProliferation markers play a significant role in the biologic behavior of tumors. Geminin is a known inhibitor of the cell cycle and DNA replication and has not been previously reported in cutaneous basal and squamous cell carcinomas of the head and neck.ObjectivesWe aimed to investigate proliferation markers ki67, MCM2, and geminin in head and neck cutaneous basal and squamous cell carcinomas.MethodsForty cases of each tumor were immuostained with ki67, MCM2, and geminin followed by assessment of labeling indices (LIs). MCM2/ki67- and geminin/ki67-ratios were also determined; t-test was used for statistical analysis (p < 0.05).ResultsThere was no significant difference in ki67 (p = 0.06) and MCM2 (p = 0.46) between cutaneous basal and squamous cell carcinomas; however, geminin LI was significantly higher in squamous cell carcinomas compared to cutaneous basal cell carcinomas (p < 0.001). Only geminin/ki67 showed a significant difference between the two tumors with the ratio showing significantly higher numbers in squamous cell carcinomas (p = 0.015).ConclusionsGeminin could be regarded as an effective factor in the pathogenesis of head and neck cutaneous cutaneous basal cell carcinomas and squamous cell carcinomas and may be one of the responsible elements in the difference between the biologic behavior of these tumors. 相似文献
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《Clinical neurophysiology》2019,130(5):727-738
ObjectiveFunctional processes in the brain are segregated in both the spatial and spectral domain. Motivated by findings reported at the cortical level in healthy participants we test the hypothesis in the basal ganglia of Parkinson’s disease patients that lower frequency beta band activity relates to motor circuits associated with the upper limb and higher beta frequencies with lower limb movements.MethodsWe recorded local field potentials (LFPs) from the subthalamic nucleus using segmented “directional” DBS leads, during which patients performed repetitive upper and lower limb movements. Movement-related spectral changes in the beta and gamma frequency-ranges and their spatial distributions were compared between limbs.ResultsWe found that the beta desynchronization during leg movements is characterised by a strikingly greater involvement of higher beta frequencies (24–31 Hz), regardless of whether this was contralateral or ipsilateral to the limb moved. The spatial distribution of limb-specific movement-related changes was evident at higher gamma frequencies.ConclusionLimb processing in the basal ganglia is differentially organised in the spectral and spatial domain and can be captured by directional DBS leads.SignificanceThese findings may help to refine the use of the subthalamic LFPs as a control signal for adaptive DBS and neuroprosthetic devices. 相似文献
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目的 观察体外冲击波联合背根神经节脉冲射频治疗脊柱源性腹痛的临床疗效。 方法 采用随机数字表法将88例脊柱源性腹痛患者分为对照组、冲击波组、脉冲射频组及联合组,所有患者均连续口服药物依托考昔、普瑞巴林3周;冲击波组患者在此基础上辅以体外冲击波治疗,脉冲射频组在此基础上辅以背根神经节脉冲射频治疗,联合组患者则辅以体外冲击波及背根神经节脉冲射频治疗。于治疗前、治疗1周、4周及12周时分别采用视觉模拟评分法(VAS)、生活质量评估量表(QOL-SF36)、汉密尔顿焦虑量表(HAMA)及汉密尔顿抑郁量表(HAMD)对4组患者进行疗效评定,并于治疗结束后2年随访4组患者疾病发展、胃肠道功能、就诊情况以及医疗花费等。 结果 治疗4周时发现4组患者疼痛VAS、QOL-SF36、HAMA及HAMD评分均较治疗前明显改善(P<0.05);其中联合组疼痛VAS评分[(0.67±0.72)分]、QOL-SF36评分[(139.00±10.54)分]、HAMA评分[(3.81±3.78)分]及HAMD评分[(4.36±4.16)分]亦显著优于对照组、冲击波组及脉冲射频组水平,组间差异均具有统计学意义(P<0.05),并且联合组这种疗效优势持续保持至治疗12周时。治疗结束后通过2年随访,发现联合组患者胃肠道症状、就诊次数、医疗花费等均较对照组、冲击波组及脉冲射频组明显减少,组间差异均具有统计学意义(P<0.05)。 结论 体外冲击波联合背根神经节脉冲射频治疗脊柱源性腹痛临床疗效显著,同时还能显著降低患者医疗费用,具有明显经济、社会效益,值得临床推广、应用。 相似文献
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