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1.
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.
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   
3.
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   
4.
The digestive properties of Australian elapid snake venoms have not been studied to any great extent. To address this, the in vitro digestive properties of Oxyuranus scutellatus (Australian Coastal Taipan) venom were investigated in a simulation of the in vivo conditions using the parameters reported for the stomach of snakes and representative prey for this species. The amount of soluble protein released was measured over time using a bicinchoninic acid (BCA) assay. Dismembered mouse hindlegs were injected intramuscularly with 0.1 ml O. scutellatus venom (concentration 10 mg/ml) and maintained in a micro-anaerobic, acidic environment (pH approximately 1.2-1.7) at 25 degrees C. The bathing liquid was sampled every 24 h for 7 days, and assayed for soluble protein. Statistical analysis revealed that O. scutellatus venom increased the rate at which proteins were released when compared to a negative control suggesting the potential importance of envenomation in the digestion of whole prey.  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.
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   
7.
目的观察中西医结合治疗外阴色素减退性疾病的近期及远期疗效。方法将100例患者随机分为2组。治疗组55例以中药外阴熏洗配合自制复方维生素B6软膏涂擦、微波局部照射综合治疗;对照组45例以2%氢化可的松软膏涂擦治疗,3个月后、1年后对近期疗效与远期疗效进行比较。结果治疗组和对照组近期治愈率分别为27.27%、8.89%(P〈0.05),有效率分别为100.00%、82.22%(P〉0.05);远期有效率治疗组和对照组分别为87.27%、26.67%(P〈0.01);复发率分别为12.73%、73.33%(P〈0.01)。结论中西医结合疗法治疗外阴色素减退性疾病疗效显著。  相似文献   
8.
目的探讨间接喉镜下或鼻内镜下微波热凝治疗声带息肉或小结的效果。方法对321例在间接喉镜或鼻内镜下微波热凝治疗声带息肉或小结病例资料进行分析。结果321例患者均一次手术成功。术后随诊3个月~一年以上的321例患者,治愈率92%,好转率8%。无效率为0。术中和术后未发生并发症。结论间接喉镜下或鼻内镜下微波热凝治疗声带息肉声带小结,具有操作安全、方便、不出血、快捷、简单、治愈率高等优点。  相似文献   
9.
高功率微波辐照对大鼠血睾屏障通透性的影响   总被引:9,自引:0,他引:9       下载免费PDF全文
目的 探讨高功率微波(HPM)辐照大鼠睾丸对血睾屏障的影响。方法 雄性SD大鼠35只,随机分为7组,每组5只。6组为辐照组,1组为对照组。于辐照后2、6、12、4.8、96h和8d活杀大鼠后取双侧睾丸组织各约1mm^3,镧-醛固定液固定后制备电镜标本,在透射电镜下进行观察。结果 对照组可见硝酸镧主要沉积在曲细精管基膜部和精原细胞周围,未越过紧密连接;辐照后2-6h电镜下所见与对照组大致相同;辐照后12-96h,从基底部到管腔面的各层生精细胞之间、支持细胞内都有大量的镧颗粒沉积;辐照后8d,仍可见细胞间隙增大,部分区域靠近精子表面的镧颗粒沉积甚至比前面时间点的更为严重。结论 高功率微波辐照能够改变细胞的通透性,破坏血睾屏障的保护作用。  相似文献   
10.
The structures of asparagine-linked oligosaccharides of porcine 32 kDa enamelin are reported. The oligosaccharides were released by N-oligosaccharide glycopeptidase digestion, and the reducing ends of the oligosaccharides were derivatized with a fluorescent reagent, 2-aminopyridine. The pyridylamino oligosaccharides were separated into eight kinds of oligosaccharides. The structures of these oligosaccharides were determined by a combination of a sequential exoglycosidase digestion and a two-dimensional suger mapping technique. The oligosaccharides consisted of fucose, galactose, mannose, N-acetylglucosamine, and N-acetylneuraminic acid, and were classified into two groups according to their core-sugar chain structures; one was a biantennary-type and the other was a triantennary-type oligosaccharide. The variation of the oligosaccharides in each of these groups was caused by the differences in the number, the site, and the mode of linkage of N-acetylneuraminic acid to the core-sugar chains.  相似文献   
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