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Systematic review of ablative therapy for the treatment of renal allograft neoplasms 预览
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作者 Evaldo Favi Nicholas Raison +6 位作者 Federico Ambrogi Serena Delbue Maria Chiara Clementi Luca Lamperti Marta Perego Matteo Bischeri Mariano Ferraresso 《世界临床病例杂志》 2019年第17期2487-2504,共18页
BACKGROUND To date,there are no guidelines on the treatment of solid neoplasms in the transplanted kidney.Historically,allograft nephrectomy has been considered the only reasonable option.More recently,nephron-sparing... BACKGROUND To date,there are no guidelines on the treatment of solid neoplasms in the transplanted kidney.Historically,allograft nephrectomy has been considered the only reasonable option.More recently,nephron-sparing surgery (NSS) and ablative therapy (AT) have been proposed as alternative procedures in selected cases.AIM To review outcomes of AT for the treatment of renal allograft tumours.METHODS We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 Checklist.PubMed was searched in March 2019 without time restrictions for all papers reporting on radiofrequency ablation (RFA),cryoablation (CA),microwave ablation (MWA),high-intensity focused ultrasound (HIFU),and irreversible electroporation (IRE) of solid tumours of the kidney allograft.Only original manuscripts describing actual cases and edited in English were considered.All relevant articles were accessed in full text.Additional searches included all pertinent references.Selected studies were also assessed for methodological quality using a tool based on a modification of the Newcastle Ottawa scale.Data on recipient characteristics,transplant characteristics,disease characteristics,treatment protocols,and treatment outcomes were extracted and analysed.Given the nature and the quality of the studies available (mostly retrospective case reports and small retrospective uncontrolled case series),a descriptive summary was provided.RESULTS Twenty-eight relevant studies were selected describing a total of 100 AT procedures in 92 patients.Recipient age at diagnosis ranged from 21 to 71 years whereas time from transplant to diagnosis ranged from 0.1 to 312 mo.Most of the neoplasms were asymptomatic and diagnosed incidentally during imaging carried out for screening purposes or for other clinical reasons.Preferred diagnostic modality was Doppler-ultrasound scan followed by computed tomography scan,and magnetic resonance imaging.Main tumour types were: papillary renal cell carcinoma (RCC) and clear cel 展开更多
关键词 ABLATIVE therapy CRYOABLATION Radiofrequency ablation Microwave ablation High-intensity focused ultrasonography IRREVERSIBLE ELECTROPORATION Neoplasm Kidney TRANSPLANT Renal ALLOGRAFT Systematic review
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Hydrochloric acid enhanced radiofrequency ablation for treatment of large hepatocellular carcinoma in the caudate lobe: Report of three cases 预览
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作者 Han-Xia Deng Jin-Hua Huang +5 位作者 Wan Yee Lau Fei Ai Min-Shan Chen Zhi-Mei Huang Tian-Qi Zhang Meng-Xuan Zuo 《世界临床病例杂志》 2019年第4期508-515,共8页
BACKGROUND To report on the use of percutaneous hydrochloric acid (HCl) enhanced radiofrequency ablation (HRFA) for the treatment of large (maximum diameter ≥ 5 cm) hepatocellular carcinoma (HCC) in the caudate lobe.... BACKGROUND To report on the use of percutaneous hydrochloric acid (HCl) enhanced radiofrequency ablation (HRFA) for the treatment of large (maximum diameter ≥ 5 cm) hepatocellular carcinoma (HCC) in the caudate lobe. CASE SUMMARY Between August 2013 and June 2016, three patients with a large HCC (maximum diameter: 5.0, 5.7, and 8.1 cm) in the caudate lobe were treated by transarterial chemoembolization followed by computer tomography (CT) guided RFA using a monopolar perfusion RF electrode, which was enhanced by local infusion of 10% HCl at 0.2 mL/min (total volume, 3 to 12 mL). The output power of HRFA reached 100 W, and the average ablation time was 39 min (range, 15 to 60 min). Two patients each underwent one session of HRFA and one patient two sessions. After treatment, CT/magnetic resonance imaging showed that all the three lesions were completely ablated. There was no major complication. Two patients had asymptomatic bile duct dilatation. One patient died of tongue cancer 24 mo after ablation. The remaining two patients were alive and no area of enhancement is detected in the caudate lobe at 28 and 60 mo after ablation, respectively. CONCLUSION Percutaneous CT-guided HRFA is safe and efficacious in treating large HCC in the caudate lobe. 展开更多
关键词 Hydrochloric ACID RADIOFREQUENCY ablation Hydrochloric ACID ENHANCED RADIOFREQUENCY ablation CAUDATE LOBE Large hepatocellular carcinoma Case REPORT
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Feasibility and safety of cryoballoon ablation for atrial fibrillation in patients with congenital heart disease 预览
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作者 Sylvia Abadir Victor Waldmann +4 位作者 Katia Dyrda Mikael Laredo Blandine Mondésert Marc Dubuc Paul Khairy 《世界心脏病学杂志:英文版(电子版)》 2019年第5期149-158,共10页
BACKGROUND The prevalence of atrial fibrillation (AF) is on the rise in the aging population with congenital heart disease (CHD). A few case series have described the feasibility and early outcomes associated with rad... BACKGROUND The prevalence of atrial fibrillation (AF) is on the rise in the aging population with congenital heart disease (CHD). A few case series have described the feasibility and early outcomes associated with radiofrequency catheter ablation of AF centered on electrically isolating pulmonary veins (PV) in patients with CHD. In contrast, cryoballoon ablation has not previously been studied in this patient population despite its theoretical advantages, which include a favorable safety profile and shorter procedural time. AIM To assess the safety and feasibility of cryoballoon ablation for AF in an initial cohort of patients with CHD. METHODS The study population consisted of consecutive patients with CHD and cryoballoon ablation for AF at the Montreal Heart Institute between December 2012 and June 2017. Procedural complications, acute success, and 1-year freedom from recurrent AF after a single procedure with or without antiarrhythmic drugs were assessed. Procedures were performed under conscious sedation. Left atrial access was obtained via a single transseptal puncture or through an existing atrial septal defect (ASD). Cryoballoon occlusion was assessed by distal injection of 50% diluted contrast into the pulmonary vein. At least one 240-second cryothermal application was performed upon obtaining complete pulmonary vein occlusion. Following ablation, patients were routinely followed at outpatient visits at 1, 3, 6, and 12 mo, and then annually. RESULTS Ten patients, median age 57.9 (interquartile range 48.2-61.7) years, 60% female, met inclusion criteria and were followed for 2.8 (interquartile range 1.4-4.5) years.Two had moderately complex CHD (sinus venosus ASD with partial anomalous pulmonary venous return;aortic coarctation with a persistent left superior vena cava), with the remainder having simple defects. AF was paroxysmal in 8 (80.0%) and persistent in 2 (20.0%) patients. The pulmonary vein anatomy was normal in 6 (60.0%) patients. Four had left common PV (n = 3) and/or 3 right PV (n = 2). Electrica 展开更多
关键词 CONGENITAL heart disease ATRIAL FIBRILLATION CRYOBALLOON ablation Pulmonary vein isolation CATHETER ablation
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The clinical efficacy analysis of radiofrequency ablation combined with chemotherapy in treating late non-small cell lung cancer 预览
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作者 Ying-Ying Liu Feng Xu 《TMR肿瘤》 2019年第3期216-221,共6页
Objective:To study the short-term efficacy and improvement effect on the quality of life of CT guided radiofrequency ablation(RFA)in treating late non-small cell lung cancer.Methods:317 patients with non-small cell lu... Objective:To study the short-term efficacy and improvement effect on the quality of life of CT guided radiofrequency ablation(RFA)in treating late non-small cell lung cancer.Methods:317 patients with non-small cell lung cancer(87 cases in the observation group and 230 cases in the control group)were selected for propensity score matching,with a matching tolerance of 0.05,and 42 pairs were successfully paired.The changes in chest enhanced CT before and 3 months after treatment and the quality of life measurement scale EORTC QLQ-C30 in Chinese version were evaluated.Results:The disease control rate of the observation group was 88.09%,which was significantly higher than that of the control group(61.91%).The functional and symptom scores of the two groups after treatment were significantly better than those before treatment,and the indicators of the observation group after treatment were better than those of the control group(P<0.05).Conclusion:CT-guided radiofrequency ablation combined with chemotherapy is safe and effective in the treatment of NSCLC,which can control local tumor progression,reduce tumor burden,and improve the quality of life of patients with advanced NSCLC. 展开更多
关键词 CT guided Radiofrequency ablation Non-small cell lung cancer QLQ-C30
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Histogram analysis of apparent diffusion coefficient predicts response to radiofrequency ablation in hepatocellular carcinoma 预览
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作者 Xiaohong Ma Han Ouyang +3 位作者 Shuang Wang Meng Wang Chunwu Zhou Xinming Zhao 《中国癌症研究:英文版》 SCIE CAS CSCD 2019年第2期366-374,共9页
Objective: The aim of this study was to predict tumor progression in patients with hepatocellular carcinoma(HCC) treated with radiofrequency ablation(RFA) using histogram analysis of apparent diffusion coefficients(AD... Objective: The aim of this study was to predict tumor progression in patients with hepatocellular carcinoma(HCC) treated with radiofrequency ablation(RFA) using histogram analysis of apparent diffusion coefficients(ADC).Methods: Breath-hold diffusion weighted imaging(DWI) was performed in 64 patients(33 progressive and 31 stable) with biopsy-proven HCC prior to RFA. All patients had pre-treatment magnetic resonance imaging(MRI)and follow-up computed tomography(CT) or MRI. The ADC values(ADC10, ADC30, ADCmedian and ADCmaxwere obtained from the histogram’s 10 th, 30 th, 50 th and 100 th percentiles. The ratios of ADC10, ADC(30,ADCmedian and ADCmax to the mean non-lesion area-ADC(RADC10, RADC30, RADCmedian, and RADCmax were calculated. The two patient groups were compared. Key predictive factors for survival were determined using the univariate and multivariate analysis of the Cox model. The Kaplan-Meier survival analysis was performed, and pairs of survival curves based on the key factors were compared using the log-rank test.Results: The ADC(30, ADCmedian, ADCmax, RADC(30, RADCmedian, and RADCmax were significantly larger in the progressive group than in the stable group(P<0.05). The median progression-free survival(PFS) was 22.9 months for all patients. The mean PFS for the stable and progressive groups were 47.7±1.3 and 9.8±1.3 months,respectively. Univariate analysis indicated that RADC10, RADC(30, and RADCmedian were significantly correlated with the PFS [hazard ratio(HR)=31.02, 43.84, and 44.29, respectively, P<0.05 for all]. Multivariate analysis showed that RADCmedian was the only independent predictor of tumor progression(P=0.04). And the cutoff value of RADCmedian was 0.71.Conclusions: Pre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA. 展开更多
关键词 DIFFUSION-WEIGHTED imaging APPARENT diffusion coefficient HISTOGRAM analysis HEPATOCELLULAR carcinoma RADIOFREQUENCY ablation survival time
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不同射速对身管内壁烧蚀的影响 预览
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作者 贡芬云 姚养无 贾陆阳 《火力与指挥控制》 CSCD 北大核心 2019年第7期85-89,共5页
为了研究自动武器身管在不同射速条件下的熔化烧蚀状况,利用有限元的方法,用Abaqus软件建立身管的瞬态传热模型。基于传热学的理论,在射速分别为300发/min.400发/min以及600发/min状态下对身管的对流传热进行模拟仿真,得到身管内壁表面... 为了研究自动武器身管在不同射速条件下的熔化烧蚀状况,利用有限元的方法,用Abaqus软件建立身管的瞬态传热模型。基于传热学的理论,在射速分别为300发/min.400发/min以及600发/min状态下对身管的对流传热进行模拟仿真,得到身管内壁表面在发射过程时的温度。然后建立身管烧蚀模型,再根据所建立的烧蚀模型计算出身管内壁烧蚀的厚度。对比在不同射速下身管的烧蚀情况,得出身管内壁的烧蚀规律。上述研究为合理安排射速以及身管寿命预测提供了有益的参考。 展开更多
关键词 身管 烧蚀 瞬态传热 射速
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Evaluation of numerical ablation model for charring composites
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作者 LI Wei ZHANG Jun +3 位作者 FANG GuoDong LI WeiJie LIANG Jun MENG SongHe 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第8期1322-1330,共9页
Charring composites are widely used in the thermal protection system(TPS) to consume the intense aerodynamic heating during vehicle reentry. The ablation and thermal responses for the charring composites can be studie... Charring composites are widely used in the thermal protection system(TPS) to consume the intense aerodynamic heating during vehicle reentry. The ablation and thermal responses for the charring composites can be studied by using a numerical ablation model, in which the surface ablation and volume ablation could be taken into account. The coupling interactions among temperature, gas motion and interior pressure producing the pyrolysis gas could make the computation more complicated. A multi-physics model is developed to simulate the thermal response coupled with volume ablation and surface ablation. After studying four typical ablation cases, the model is validated, and then the heat transfer mechanisms in ablation are investigated. It is found that the viscous dissipation energy by the motion of pyrolysis gas can be neglected in the simulation. Also, the flow of pyrolysis gas plays an important role in the temperature response, especially under high heat flux condition. 展开更多
关键词 ablation CHARRING COMPOSITES NUMERICAL MODEL COUPLING
Treatment of refractory ventricular tachycardia with combination of alcohol ablation and radiofrequency ablation 预览
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作者 Zhong-Hai WEI Wen-Zhi SHEN +5 位作者 Jian BAI Jun XIE Wen-Qing JI Lian WANG Wei XU Biao XU 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第8期660-662,共3页
The post-infarcted related ventricular tachycardia (VT) is considered associated with increase in mortality or sudden cardiac death (SCD). Implantable cardioverter defibrillation (ICD) has been the standard therapy fo... The post-infarcted related ventricular tachycardia (VT) is considered associated with increase in mortality or sudden cardiac death (SCD). Implantable cardioverter defibrillation (ICD) has been the standard therapy for the first or second prevention of SCD after myocardial infarction (MI). Incessant VT, which has poor response to anti-arrhythmic drugs and can cause repetitive ICD shock, is usually a tough problem in clinical practice. According to the guideline, incessant infracted related VT could be treated with catheter ablation.[1] Herein we reported a case of refractory scar-induced VT accompanied with thrombus in the left chamber, which was full with ups and downs during the therapy. 展开更多
关键词 Ablation ARRHYTHMIA MYOCARDIAL INFARCTION VENTRICULAR TACHYCARDIA
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QD128燃气轮机涡流器组件与喷嘴磨损、烧蚀及积炭问题研究 预览
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作者 王巍龙 李明 +1 位作者 牟影 新吉勒 《燃气轮机技术》 2019年第3期25-33,共9页
本文对QD128燃气轮机涡流器组件与喷嘴磨损、烧蚀及积炭问题进行研究分析,从零件材料、结构尺寸到材料表面处理入手,提出解决故障的方法,通过将浮动环材料改为线胀系数更小的GH907,缩短轴向尺寸、增加抑制旋转结构及耐磨涂层来解决磨损... 本文对QD128燃气轮机涡流器组件与喷嘴磨损、烧蚀及积炭问题进行研究分析,从零件材料、结构尺寸到材料表面处理入手,提出解决故障的方法,通过将浮动环材料改为线胀系数更小的GH907,缩短轴向尺寸、增加抑制旋转结构及耐磨涂层来解决磨损问题,通过将喷嘴头部表面材料改性处理、周向开槽以及端面前移2mm的方法来解决积炭问题,并且利用数值仿真,在75%和100%负荷下,对比原始结构及改进结构对火焰筒头部及燃烧室性能参数的影响,验证改进方法的可行性。 展开更多
关键词 磨损 烧蚀 积炭 故障 数值仿真
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心内电检查对快速心律失常的诊断疗效研究 预览
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作者 梅帆 聂钰君 《中国继续医学教育》 2019年第9期61-63,共3页
目的探讨心内电生理检查对快速性心律失常诊断和疗效。方法选取2017年3月-2018年3月我院收治的快速性心律失常患者84例作为研究对象。所有患者均进行心内电生理检查,射频消融术治疗。分析心内电生理检查心律失常的检出率、射频消融术治... 目的探讨心内电生理检查对快速性心律失常诊断和疗效。方法选取2017年3月-2018年3月我院收治的快速性心律失常患者84例作为研究对象。所有患者均进行心内电生理检查,射频消融术治疗。分析心内电生理检查心律失常的检出率、射频消融术治疗不同病因引发的心律失常的疗效。结果 84例快速性心律失常患者均经过心内电生理检查,其中预激合并室上性心动过速10例,房性心动过速8例,2∶1房扑12例,室内心动过速13例,房室旁路12例,房室结双径路25例,此次研究共检查出80例快速心率失常患者,检出率为95.2%;80例快速心率失常患者均经过射频消融术治疗取得了一定的效果,治疗成功率为100%。结论快速性心律失常诊断和治疗过程中,心内电生理检查、射频消融术治疗疗效满意。 展开更多
关键词 心内电生理检查 快速性心律失常 射频 消融术 诊断 疗效
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高压单芯电缆外护套烧蚀故障分析 预览
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作者 吴俊鹏 《集成电路应用》 2019年第2期119-120,共2页
高压单芯电缆在供电中发挥着非常重要的作用。研究表明,高压电缆会因其护套外产生悬浮电压或环流等因素,引起电缆外套的烧损,从而引发安全事故,影响供电网络的安全运行。所以,非常有必要研究高压电缆护套烧蚀机理及应该采取的相应保护... 高压单芯电缆在供电中发挥着非常重要的作用。研究表明,高压电缆会因其护套外产生悬浮电压或环流等因素,引起电缆外套的烧损,从而引发安全事故,影响供电网络的安全运行。所以,非常有必要研究高压电缆护套烧蚀机理及应该采取的相应保护措施。 展开更多
关键词 高压电缆 电缆护套 烧蚀 故障分析
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Long-term survival of a patient with advanced pancreatic cancer under adjunct treatment with Viscum album extracts: A case report 预览
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作者 Paul G Werthmann Robert Kempenich +1 位作者 Gerlinde Lang-Avérous Gunver S Kienle 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第12期1524-1530,共7页
BACKGROUND Advanced pancreatic cancer (aPC) has a poor prognosis with limited survival benefit from current standard treatment. Viscum album extracts (VAE) are used by many cancer patients, showing immune-stimulating ... BACKGROUND Advanced pancreatic cancer (aPC) has a poor prognosis with limited survival benefit from current standard treatment. Viscum album extracts (VAE) are used by many cancer patients, showing immune-stimulating effects, improved quality of life, and a survival benefit in patients with aPC. CASE SUMMARY A 59-year-old architect developed epigastric pain. A cystic lesion of the pancreas of 45-mm diameter was detected. In a follow-up magnetic resonance imaging, about one year later, multiple lesions were seen in the corpus and the tail of the pancreas;CA-19-9 was elevated to 58.5 U/mL. A distal pancreatectomy with splenectomy was performed, and a tumor of 7 cm×5 cm×3.5 cm was excised. Histologic investigation showed an intraductal papillary mucinous neoplasmassociated invasive adenocarcinoma with invasion of the lymph vessels, perineural invasion, and positive nodes (2/27);surgical margins showed tumor cells, and the tumor was classified as pT3 N1 M0 R1. The patient was treated with radiation of the tumor bed and capecitabine/oxaliplatin followed by gemcitabine and FOLFIRINOX. Seven months after surgery, a liver metastasis was detected and treatment with FOLFIRINOX was started. Four months after detection of the metastasis, the patient opted for additional treatment with VAE. Another month later, the metastasis was treated with radiofrequency ablation (RFA). Eight months later, the hepatic lesion recurred and was again treated with RFA. The continuous VAE treatment was increased in dose, and the patient stayed recurrence-free for the next 39 mo in good health and working full-time (as of the time this case report was written). CONCLUSION We present the case of a patient with aPC with R1-resection with development of liver metastasis during the course of treatment who showed an overall survival of 63 mo and a relapse-free survival of 39 mo under increasing VAE therapy. The possible synergistic effect on tumor control of RFA treatment and immunestimulatory effects of VAE should be further investigated. 展开更多
关键词 PANCREATIC cancer INTEGRATIVE medicine Viscum ALBUM extract RADIOFREQUENCY ablation Case report
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Development of a biliary multi-hole self-expandable metallic stent for bile tract diseases: A case report 预览
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作者 Makoto Kobayashi 《世界临床病例杂志》 2019年第11期1323-1329,共7页
BACKGROUND Uncovered stents used for malignant obstructions in the biliary tree, especially in the hilar area, are prone to obstruction by tumor ingrowths. In comparison, however, covered stents may block bile duct br... BACKGROUND Uncovered stents used for malignant obstructions in the biliary tree, especially in the hilar area, are prone to obstruction by tumor ingrowths. In comparison, however, covered stents may block bile duct branches and are at risk of migration. We have developed a multi-hole self-expandable metallic stent (MHSEMS), with a hole in each cell, to prevent the obstruction of bile duct branches. In addition, the holes may prevent migration due to small ingrowths by reducing the tension of the membrane. CASE SUMMARY MHSEMS were placed in five patients with a malignant obstruction and one with post-endoscopic sphincterotomy bleeding. Each MHSEMS was successfully deployed in all cases. Patients showed no complications. Two cases were reviewed. Case 1: A 74-year-old male presented with jaundice and was diagnosed with a sigmoid colon cancer and giant liver metastases in the right liver lobe. A MHSEMS was placed in the left bile duct. The jaundice improved and peroral cholangioscopy was performed. Case 2: A 90-year-old female was admitted to hospital for jaundice and diagnosed with cholangiocarcinoma. A MHSEMS was placed in the left bile duct but after 8 months the stent became obstructed by tumor ingrowth. We treated the patient by ablation therapy. A silicone cover separated the internal bile duct from the surrounding tissue, protecting the latter from thermal injury during treatment by endobiliary ablation of the reobstruction. CONCLUSION A MHSEMS is a new choice of stent for biliary tract diseases. 展开更多
关键词 Multi-hole self-expandable metallic stent Malignant BILIARY STRICTURE Benign BILIARY STRICTURE HILAR BILIARY OBSTRUCTION Distal BILIARY OBSTRUCTION Endobiliary radiofrequency ablation Case report
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Safety and efficacy of transjugular intrahepatic portosystemic shunt combined with palliative treatment in patients with hepatocellular carcinoma 预览
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作者 Shi-Hua Luo Jian-Guo Chu +1 位作者 He Huang Ke-Chun Yao 《世界临床病例杂志》 2019年第13期1599-1610,共12页
BACKGROUND There is a close relationship between cirrhosis and hepatocellular carcinoma (HCC). Transjugular intrahepatic portosystemic shunt (TIPS) has good clinical effect in treating the complication of portal hyper... BACKGROUND There is a close relationship between cirrhosis and hepatocellular carcinoma (HCC). Transjugular intrahepatic portosystemic shunt (TIPS) has good clinical effect in treating the complication of portal hypertension. However, because of the risk of postoperative liver failure, severe complications, and low survival rate for HCC, TIPS is contraindicated in patients with portal hypertension and liver cancer. We studied a large cohort of patients with cirrhosis and HCC who underwent TIPS for recurrent variceal bleeding and/or ascites. AIM To assess the safety, efficacy, and survival rate in patients with HCC who underwent TIPS. METHODS Group A comprised 217 patients with HCC and portal hypertension who underwent the TIPS procedure between 1999 and 2014. After TIPS deployment, these patients received palliative treatment for HCC. Group B comprised a cohort of 136 HCC patients with portal hypertension who did not undergo TIPS placement. Group B received palliative treatment for HCC plus medical therapy for portal hypertension. The clinical outcomes and survival rate were assessed. RESULTS In Group A, the primary technical success rate was 97.69% for TIPS placement,and no severe procedure-related complications of TIPS placement were reported. The control of variceal bleeding (VB) within 1 mo did not differ significantly between the groups (P = 0.261). Absorption of refractory ascites within 1 mo, recurrence of VB, and recurrence of refractory ascites differed significantly between the groups (P = 0.017, 0.023, and 0.009, respectively). By comparison, the rate of hepatic encephalopathy in Group B was lower than that in Group A (P = 0.036). The 1-, 2-, 3-, 4-, and 5-year survival rates were significantly different between Groups A and B (χ^2 = 12.227, P = 0.018;χ^2 = 12.457, P = 0.014;χ^2 = 26.490, P = 0.013;χ^2 = 21.956, P = 0.009, and χ^2 = 24.596, P = 0.006, respectively). The mean survival time was 43.7 mo in Group A and 31.8 mo in Group B. Median survival time was 50.0 mo in Group A and 33.0 mo in Grou 展开更多
关键词 HEPATOCELLULAR carcinoma PORTAL hypertension Transjugular INTRAHEPATIC portosystemic SHUNT Transarterial CHEMOEMBOLIZATION RADIOFREQUENCY ablation
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复合材料雷击防护电热耦合模型 预览
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作者 卢翔 赵淼 +1 位作者 单泽众 罗名俊 《航空材料学报》 CAS CSCD 北大核心 2019年第4期49-58,共10页
为了研究复合材料雷击防护(lightning strike protection,LSP)系统在雷电流作用下的损伤规律,基于雷击过程中的能量守恒关系,建立复合材料层合板雷击防护的电-热耦合数学模型。在此基础上,在ABAQUS中建立铝涂层防护的碳纤维增强复合材料... 为了研究复合材料雷击防护(lightning strike protection,LSP)系统在雷电流作用下的损伤规律,基于雷击过程中的能量守恒关系,建立复合材料层合板雷击防护的电-热耦合数学模型。在此基础上,在ABAQUS中建立铝涂层防护的碳纤维增强复合材料(carbon fiber reinforced polymer,CFRP)层合板雷击烧蚀损伤有限元模型,并对雷击烧蚀损伤进行分析,和实验结果对比验证仿真的有效性,得出复合材料层合板在不同峰值雷电流、不同组合波形和不同铝涂层厚度雷电流作用下的烧蚀损伤规律。结果表明:铝涂层厚度相同时,峰值电流从50kA 增大到100kA时,复合材料层合板损伤面积约增大 1.5 倍;10/350波形50 kA峰值雷电流作用下,基准件的损伤面积约为0.05 mm厚度铝涂层防护系统下复合材料损伤面积的4倍。 展开更多
关键词 雷击 复合材料 电热耦合 损伤 烧蚀
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磁共振引导超声聚焦系统(“磁波刀”)在治疗特发性震颤中的应用 预览
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作者 宗睿 何建风 +8 位作者 张德康 黄立超 李雪梅 余新光 凌至培 赵珺燕 马林 娄昕 潘隆盛 《解放军医学院学报》 CAS 2019年第1期1-6,共6页
目的验证'磁波刀'治疗药物难治性特发震颤的有效性和安全性。方法根据ET002J临床试验方案,筛选解放军总医院第一医学中心受试者于2019年1月进行治疗。采用临床震颤评定量表(CRST)评价震颤症状。所有患者采取'磁波刀'左... 目的验证'磁波刀'治疗药物难治性特发震颤的有效性和安全性。方法根据ET002J临床试验方案,筛选解放军总医院第一医学中心受试者于2019年1月进行治疗。采用临床震颤评定量表(CRST)评价震颤症状。所有患者采取'磁波刀'左侧丘脑腹中间核毁损术治疗。结果入选受试者男性2例,女性1例,年龄分别为66岁、76岁和66岁;病程均超过10年,均有家族史,确诊为难治性特发震颤。治疗后,429301号受试者CRST量表中Part A评分从术前20分改善到11分,429302号受试者从16分改善到6分,429303号受试者从16分改善到7分,平均改善超过50%。所有受试者书写能力均得到明显改善。术后除1例出现短暂平衡障碍,其余受试者无不良反应。结论本中心完成的3例药物难治性特发震颤的'磁波刀'治疗,取得良好治疗效果,初步验证了该设备对特发震颤治疗的适用性,为其下一步应用治疗于中枢神经系统其他重大疾病奠定了基础。 展开更多
关键词 特发震颤 磁共振引导超声聚焦 消融 丘脑腹中间核 丘脑切开术 中枢神经系统疾病
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硅橡胶绝热材料气相环境烧蚀特性试验研究
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作者 王书贤 李江 《化工新型材料》 CAS CSCD 北大核心 2019年第6期136-139,143共5页
采用试验发动机,在双基推进剂的气相燃气环境中对一种硅橡胶绝热材料进行烧蚀特性研究,分析了环境气流速度及压强对硅橡胶绝热材料碳化烧蚀率及炭化层宏观和微观结构形貌的影响。结果表明:在无粒子作用条件下,环境气流速度和压强通过对... 采用试验发动机,在双基推进剂的气相燃气环境中对一种硅橡胶绝热材料进行烧蚀特性研究,分析了环境气流速度及压强对硅橡胶绝热材料碳化烧蚀率及炭化层宏观和微观结构形貌的影响。结果表明:在无粒子作用条件下,环境气流速度和压强通过对流热流、炭化层外部和内部气动力影响硅橡胶绝热材料的烧蚀特性。气流速度高,碳化烧蚀率大,炭化层薄且致密;环境压强高,碳化烧蚀率大,炭化层易分层鼓包。同时将硅橡胶绝热材料的烧蚀特性与相同实验条件下的三元乙丙橡胶绝热材料进行了对比,为进一步对绝热材料进行烧蚀机理分析和建模计算打下基础。 展开更多
关键词 硅橡胶绝热材料 烧蚀 气相环境 宏观-微观结构
足头向穿刺路径在膈肌下方肝肿瘤消融治疗中的CT模拟测量研究 预览
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作者 刘源 李曦 +5 位作者 张莉敏 王奇奇 刘洋 王科 钟森 何春水 《西部医学》 2019年第1期128-135,共8页
目的对足头向穿刺路径进行模拟测量并评价在膈肌下方肝肿瘤热消融治疗中的临床应用价值。方法重建患者上腹部CT图像,选取有代表性的3个矢状面和1个冠状面作为标准层面,在各层面建立膈下标准病灶模型,并采用足头向穿刺路径进行模拟穿刺... 目的对足头向穿刺路径进行模拟测量并评价在膈肌下方肝肿瘤热消融治疗中的临床应用价值。方法重建患者上腹部CT图像,选取有代表性的3个矢状面和1个冠状面作为标准层面,在各层面建立膈下标准病灶模型,并采用足头向穿刺路径进行模拟穿刺。测量各平面上膈肌高度、穿刺路径长度及间距。采用可到达性评价模拟穿刺时穿刺针分布于标准病灶中的最理想的位置情况。结果纳入86例患者行测量研究,多数患者矢状2、3面的膈肌高度低于2cm,仅分别对平面内15.11%的病灶e和8.13%的病灶f进行了测量。标准病灶a、b、c、d、b’的完全到达比例分别为52.43%、60.97%、38.37%、52.94%、63.53%,中位路径长度分别为10.39cm、13.37cm(背侧,腹侧12.66cm)、13.15cm、8.88cm、11.26cm,中位穿刺路径间距分别为2.1cm、2.09cm(背侧,2.14cm腹侧)、2.06cm、2.11cm、2.145cm。结论采用足头向穿刺路径进行穿刺,标准病灶a、b、d、b’有较高的完全到达比例,穿刺宽容度较高,有进一步在临床中应用的价值。标准病灶c的完全到达率不高。标准病灶e、f需要采用该路径穿刺的比例不高。 展开更多
关键词 足头向穿刺路径 膈肌下方病灶 消融 安全性 可到达性 宽容度 模拟测量
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Hierarchical microstructures with high spatial frequency laser induced periodic surface structures possessing different orientations created by femtosecond laser ablation of silicon in liquids 预览
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作者 Dongshi Zhang Koji Sugioka 《光电进展(英文)》 2019年第3期1-18,共18页
High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or micro... High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles. 展开更多
关键词 HIGH spatial frequency LASER induced periodic SURFACE structures SILICON LASER ablation in liquids HIERARCHICAL MICROSTRUCTURES femtosecond LASER HIGH fluence formation mechanism SURFACE melting nanocapillary wave SURFACE plasmon polaritons second-harmonic generation
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一种固体发动机喷管喉衬烧蚀传热计算方法 预览
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作者 裴少帅 《机械》 2019年第7期26-29,41共5页
基于喷管喉衬材料在工作过程中的烧蚀模型,建立了一种喷管喉衬瞬态烧蚀传热计算方法。采用Python语言对MSC.Marc进行二次开发,引入喉衬烧蚀移动边界和瞬变内流场边界,实现了对喷管喉衬工作过程烧蚀传热计算。计算获得了喉衬工作过程中... 基于喷管喉衬材料在工作过程中的烧蚀模型,建立了一种喷管喉衬瞬态烧蚀传热计算方法。采用Python语言对MSC.Marc进行二次开发,引入喉衬烧蚀移动边界和瞬变内流场边界,实现了对喷管喉衬工作过程烧蚀传热计算。计算获得了喉衬工作过程中与高温燃气接触表面形貌变化规律和温度分布规律。计算结果表明,喉衬工作过程中考虑烧蚀时,最大径向线烧蚀率发生在瞬时喉部前端;瞬时喉部随工作时间加长向喉衬出口端移动;喉衬整体温度相比未考虑烧蚀的喉衬温度有显著差异。计算方法为喷管喉衬的精细化设计提供了设计依据,对喉衬工作过程可靠性评估具有指导意义。 展开更多
关键词 固体发动机 喷管喉衬 烧蚀 传热
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