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1.
《Journal of vascular and interventional radiology : JVIR》2020,31(12):2033-2042.e1
PurposeTo examine predictors of midterm occlusion in portal and hepatic veins within or adjacent to the ablation zone after irreversible electroporation (IRE) of liver tumors.Materials and MethodsThis retrospective cohort analysis included 39 patients who underwent CT-guided IRE of liver tumors. Vessels within or adjacent to the ablation zone were identified on CT images acquired immediately after the procedure, and the positional relationships with the ablation zone (within/adjacent), locations (proximal/distal), and diameters (< 4 mm or ≥ 4 mm) were evaluated. Using contrast-enhanced follow-up scans, each vessel was classified as patent, stenosed, or occluded. Associations between vessel occlusion and each variable were investigated.ResultsOverall, 33 portal veins and 64 hepatic veins were analyzed. Follow-up scans showed occlusion in 12/33 (36.7%) portal veins and 17/64 (26.6%) hepatic veins. Vessels within the ablation zone were occluded significantly more frequently than vessels adjacent to the ablation zone (portal: 55.6% [10/18] vs 13.3% [2/15], P = .04; hepatic: 45.4% [15/33] vs 6.4% [2/31], P = .011). Vessels with a diameter < 4 mm were also occluded significantly more frequently than vessels with a diameter ≥ 4 mm (portal: 72.7% [8/11] vs 18.1% [4/22], P = .011; hepatic: 54.8% [17/31] vs 0% [0/33], P < .001). The respective positive and negative predictive values for occlusion of vessels categorized as both within and < 4 mm were 88% (7/8) and 82% (20/25) for portal veins and 79% (15/19) and 96% (43/45) for hepatic veins.ConclusionsMidterm vessel occlusion after liver IRE could be predicted with relatively high accuracy by assessing ablation location and vessel diameter. 相似文献
2.
《Gait & posture》2019
BackgroundWhen older adults turn to sit, about 80% of the subjects complete the turn before starting to sit i.e., a distinct-strategy, while in about 20%, part of the turning and sitting take place concurrently, i.e., an overlapping-strategy. A prolonged duration of the separation between tasks in the distinct-strategy (D-interval) and a prolonged duration of the overlap interval in overlapping-strategy (O-interval) are related to worse motor symptoms and poorer cognition. In the present study, we evaluated what strategy is employed by patients with Parkinson’s disease (PD) when they transition from turning to sitting.Methods96 participants with PD performed turn to sit as part of the Timed Up and Go test, both with and without medications, while wearing a body-fixed sensor. We quantified the turn-to-sit transition and determined which strategy (distinct or overlapping) was employed. We then stratified the cases and used regression models adjusted for age, gender, height, and weight to examine the associations of the D-interval or O-interval with parkinsonian features and cognition.ResultsMost patients (66%) employed the overlapping-strategy, both off and on anti-parkinsonian medications. Longer O-intervals were associated with longer duration of PD, more severe PD motor symptoms, a higher postural-instability-gait-disturbance (PIGD) score, and worse freezing of gait. Longer D-intervals were not associated with disease duration or PD motor symptoms. Neither the D- nor O-intervals were related to cognitive function. Individuals who employed the overlapping-strategy had more severe postural instability (i.e., higher PIGD scores), as compared to those who used the distinct-strategy.SignificanceIn contrast to older adults without PD, most patients with PD utilize the overlapping strategy. Poorer postural and gait control are associated with the strategy choice and with the duration of concurrent performance of turning and sitting. Additional work is needed to further explicate the mechanisms underlying these strategies and their clinical implications. 相似文献
3.
While once considered as incurable systemic disease, treatment options for liver metastases have increased over the last 30 years and safety has improved dramatically, such that for a selected group of patients the hope of cure can now be offered with radical treatment, and low morbidity interventions can be offered which prolong survival, even in patients with more widely disseminated disease. Advances have been made in selection and surgical technique for liver resection and several adjuncts to resection now exist in the form of portal vein embolization, thermal ablation and targeted drug or radiotherapy delivery options. A natural consequence of these developments has been the delivery of services within fewer specialist units, with the result that later complications of therapy may present to local hospitals, rather than directly to the specialist centres. This article will describe the current common liver-directed therapies and outline the presentation and management of their complications. 相似文献
4.
目的:窦道是通达组织深部的盲管性创道,时发时愈,迁延日久.是临床工作者常见的问题,治疗十分困难;为探索窦道的新的治疗途径,开展了微波治疗窦道的临床研究.方法:微波组:采用微波热机局部照射 外科常规换药治疗;根据病变部位分别选择直径为10cm或16cm的辐射器,辐射器距窦道口距离为3cm~5cm,隔1d或隔2d治疗1次,每次30 min,10次为1个疗程,微波治疗功率为70W,治疗结束观察治疗效果.对照组:按外科常规换药治疗.结果:微波组痊愈率98%,好转率2%,总有效率100%;对照组痊愈率37.5%,有效率37.5%,无效率25%,总有效率75%;结论:微波治疗窦道不愈患者具有简单、安全、方便、疗效独特等优点. 相似文献
5.
为提供微波辐射安全标准必要的数据,研究了不同极化方向微波辐射能量对猕猴的影响。实验在医学微波无反射室中进行,分为电场,磁场和微波传输方向极化组,辐射频率1GHz,用红外热图技术,对暴露在三种极化方向电磁场中猕猴面部各解剖特片部位及胸部在辐射前后进行温度变化的定量分析。 相似文献
6.
脉搏波形采集与辅助诊断系统的设计 总被引:1,自引:0,他引:1
季鑫源 《中国神经再生研究》2009,13(4):655-658
在分析现有脉搏信号测量技术及其处理方法的基础上,设计了以AT89S52单片机为下位机,PC机为上位机的脉搏信号采集装置。利用Delphi强大的数据库支持特性和Delphi与Matlab混合编程技术,开发了脉搏信号辅助诊断系统。该系统界面友好,操作简单,数据处理能力强,实现了脉搏信号的采集,脉搏波形的实时显示、回放等功能。通过对临床患者脉搏数据的实际采集和处理,验证了该系统的有效性和实用性。 相似文献
7.
Color Stability of Dry Earth Pigmented Maxillofacial Silicone A-2186 Subjected to Microwave Energy Exposure 总被引:2,自引:0,他引:2
Sudarat Kiat-amnuay DDS MS ; Dennis A. Johnston PhD ; John M. Powers PhD ; Rhonda F. Jacob DDS MS 《Journal of prosthodontics》2005,14(2):91-96
PURPOSE: The purpose of this study was to measure spectrophotometrically the color stability of pigmented A-2186 silicone maxillofacial elastomer with 10% by volume of titanium white dry earth opacifier before and after exposure to microwave energy over a simulated 1.5-year period of microwave sterilization. Materials AND METHODS: A-2186 silicone elastomer opacified with titanium white dry earth pigment, pigmented with 5 cosmetic dry earth pigment colors [no pigment (control) group (Pc), red (Pr), yellow ochre (Py), burnt sienna (Po), and a mixture of Pr + Py + Po color group (P3)], was used in this study. Each of the 5 experimental groups consisted of 5 specimens. All specimens were placed in a 250 ml glass beaker filled with 150 ml of water (replenished for each microwave exposure). An exposure of 6 minutes was used 18 times (simulating 1.5 years of microwave sterilization with one 6 minute exposure monthly). Reflectance values were measured by spectrophotometer. Three- and two-way analyses of variance with repeated measures were performed for the color difference (DeltaE*) with the factors of group/color/months, and group/months, respectively. Means were compared by Tukey Honest Significant Difference (HSD) multiple range test calculated at the 0.05 level of significance using SPSS. RESULTS: The trained human eye can detect color changes (DeltaE*) greater than 1.0. Most DeltaE* values of the red pigment group at all intervals and the mixed pigment group at 15- and 18- month intervals increased significantly greater than 1.0 (p < 0.001) compared with the control group. Yellow and burnt sienna groups remained the most color stable over time with DeltaE* values below 0.35. CONCLUSIONS: Lack of color stability of red dry earth pigmented A-2186 silicone maxillofacial elastomers was clinically significant after 12-month exposure to microwave energy as compared with yellow, burnt sienna, and opacified A-2186 dry earth pigments. 相似文献
8.
9.
微波干燥法对腊叶标本压制的实验研究 总被引:2,自引:1,他引:1
目的:寻求一种不受气候条件影响而能成功制作腊叶标本的新技术。方法:采用微波干燥法,即用微波炉,由创制的直径31cm瓦楞纸板、吸水纸与玻璃皿组成的压制程序进行微波干燥。结果:微波干燥法可用于腊叶标本压制,且优于传统的常规腊叶标本压制方法。结论:本研究为腊叶标本的制作提供了一个新方法,收到了便捷、高效、且保色的理想效果。 相似文献
10.
目的:探讨改进的微波辐射器探头治疗宫颈糜烂的疗效。方法:将微波辐射器探头由双直线形、双针形、单针形等点线状改进成为“单舌形”和“双舌形”两种弧形平面探头,用于治疗宫颈糜烂。分析1999-2002年450例宫颈糜烂治疗资料,其中300例经微波治疗(A组),150例经C02—激光治疗(B组),随访1—3个月。结果:两组治疗后3个月内A组治愈率明显高于B组(P<0.005),总有效率A组明显高于B组(P<0.025)。两组术中、术后不良反应比较:术中宫颈创面出血A组明显低于B组(P<0.005),术中腹痛、脱痂期出血量、术后局部感染率方面两组相似。结论:所改进的微波辐射器探头治疗宫颈糜烂治愈率高,操作安全,术后并发症少,医患乐于接受。 相似文献