Willis覆膜支架治疗颅内段颈内动脉病变临床应用

【摘要】 目的 评价Willis覆膜支架治疗颅内段颈内动脉病变的效果。方法 回顾性分析2013年4月至2015年4月采用Willis覆膜支架治疗的201例颅内段颈内动脉病变患者。术后3～6个月随访复查DSA和临床观察结果。结果 Willis覆膜支架成功治疗198例颅内段颈内动脉病变,其中囊性动脉瘤88例,外伤性动脉瘤19例,假性动脉瘤35例,外伤性颈动脉海绵窦瘘56例,技术成功率达到98.5%。Willis覆膜支架释放部位依次为颈内动脉C7段9例,C6段28例,C5段32例,C4段110例,C3段19例;支架释放后即刻DSA显示病变完全不显影163例,内漏35例,经球囊后扩或再植入支架治疗后病变完全不显影33例（其中2例闭塞载瘤动脉）,2例仍存在内漏。术中发生支架源性血管破裂出血5例,术中成功止血4例;术后再出血1例,死亡2例。术后3～6个月随访复查DSA显示载瘤动脉通畅189例,轻度狭窄5例;病变完全不显影196例。临床随访3～20个月,存活患者无新发神经系统体征。结论 Willis覆膜支架能够安全有效地治疗颅内段颈内动脉病变,但需要更远期随访。

     

覆膜支架治疗颅内动脉疾病

近年来覆膜支架治疗颅内动脉疾病的报道渐多，由冠脉覆膜支架的临床应用过渡到专用颅内覆膜支架的基础研究和临床试验。应用覆膜支架治疗的颅内动脉疾病主要为巨大、宽颈或微小脑动脉瘤、各种原因所致的颅内动脉假性动脉瘤、椎基底动脉梭形或夹层动脉瘤和海绵窦动静脉瘘等。这类颅内动脉的病变是目前手术和血管内治疗材料和技术难以解决的。覆膜支架使用后可直接、有效封堵动脉瘤颈和瘘口，使梭形动脉瘤及载瘤血管再塑形。但也会产生脑神经功能缺失、穿支或母体血管闭塞。本文对覆膜支架治疗颅内动脉病变的国内、外应用和研究动态，所治疗的疾病部位和类型、治疗效果及存在问题进行回顾性分析。     

颅内夹层动脉瘤血管内治疗进展

【摘要】 夹层动脉瘤是颅内血管病变少见疾病之一。它是指病理性夹层发生在动脉中膜层内或中膜和外膜之间造成动脉壁膨出,发生的动脉瘤样扩张。其动脉瘤壁破裂引起的蛛网膜下腔出血是导致患者致残、致死的主要原因。由于颅内夹层动脉瘤各自不同的临床特点,尚无统一的治疗方案。目前国内外对颅内夹层动脉瘤的治疗方式主要有闭塞载瘤动脉、支架辅助弹簧圈栓塞等,两者长期随访研究结果显示缺血及出血事件无明显差异。目前国内外更为关注的是载瘤动脉的重建。一些新的治疗理念如多支架重叠重建载瘤动脉等越来越得到多数学者的推崇。本文就其血管内治疗进展予以综述,为临床治疗提供理论参考。
     

Willis覆膜支架治疗外伤性颈内动脉假性动脉瘤的中期随访

目的评价Willis覆膜支架治疗外伤性颈内动脉假性动脉瘤的疗效和中期预后。方法在３８例头颈部外伤患者的脑血管造影中发现了１３例、１４枚延迟性颈内动脉假性动脉瘤,所有假性动脉瘤使用Willis覆膜支架治疗,术后１、３、６和１２个月随访脑血管造影,分为完全闭塞和不完全闭塞;临床症状随访分为完全恢复、明显改善、无明显改善和恶化。结果所有病例成功植入Willis覆膜支架,术中无一例出现并发症。最初９例假性动脉瘤完全闭塞,４例不完全闭塞;３～１２个月随访造影显示１２例假性动脉瘤完全闭塞,所有病例颈内动脉通畅,无明显支架内狭窄。临床随访１１例完全恢复,１例改善,１例无明显改善;无致残和致死病例。结论Willis覆膜支架治疗外伤性颈内动脉假性动脉瘤是切实可行的,能够很好地保留载瘤动脉。     

颅内动脉瘤血管内治疗现状与进展

【摘要】 颅内动脉瘤破裂出血具有极高的致残率和致死率。随着技术方法、材料发展及神经介入医师经验积累,血管内治疗已成为降低破裂颅内动脉瘤再出血率和死亡率的首选治疗方法。血管内治疗主要历经载瘤动脉和动脉瘤闭塞、动脉瘤瘤腔内栓塞和载瘤动脉重建等3个研究阶段,其中应用最广泛的是瘤腔内栓塞治疗,包括单纯弹簧圈、液体栓塞剂、瘤腔内栓塞装置、球囊/支架辅助技术等。载瘤动脉重建（覆膜支架和血流导向装置）也是近期研究热点。尽管新材料和新技术发展,但难治性动脉瘤如宽颈动脉瘤血管内治疗复发率仍较高。为了完全隔绝颅内动脉瘤或实现瘤颈完全内皮化,载药弹簧圈/支架、生物可降解支架等正在研究中。

     

颅内椎动脉夹层动脉瘤介入治疗个体因素分析

【摘要】 目的 总结介入栓塞治疗颅内椎动脉夹层动脉瘤（IVADA）影像和临床效果,探讨个体化治疗策略。方法 回顾性分析2011年至2015年郑州大学第一附属医院分别采用单纯弹簧圈栓塞、夹层动脉瘤及载瘤动脉闭塞、支架辅助弹簧圈栓塞和覆膜支架植入术治疗的24例IVADA患者资料、治疗经过及临床疗效,探讨不同动脉瘤介入治疗时须考虑的个体化因素。结果 24例IVADA患者介入治疗均获成功:动脉瘤和载瘤动脉闭塞5例,弹簧圈栓塞动脉瘤1例,支架辅助弹栓塞动脉瘤16例,覆膜支架植入2例。术后临床随访平均11个月（5～29个月）,所有患者症状明显减轻或消失,无新发出血。12例获脑血管造影随访,11例夹层动脉瘤不显影,1例复发,再次介入治疗。结论 介入栓塞术治疗IVADA安全有效,须结合夹层动脉瘤是否破裂及相关临床症状、是否位于优势侧椎动脉及对侧椎动脉情况、动脉瘤形态及是否累及小脑后下动脉制定个体化治疗方案。

     

Willis覆膜支架治疗犬颈内动脉虹吸段动脉瘤的影像学和组织病理学研究

目的建立一种犬颈动脉虹吸段（CS）动脉瘤模型,并观察１２个月以测试新型Willis颅内覆膜支架系统的机械性能;评价植入支架在弯曲段血管内的组织学反应。方法通过外科手术方法建立１２只犬２４枚颈动脉直段侧壁囊性动脉瘤（A组）,和１２只犬１２枚CS动脉瘤（B组）。每枚动脉瘤行１枚覆膜支架植入治疗。以血管造影方法评价支架植入即刻,１、３、６和１２个月随访动脉瘤闭塞、支架内漏、支架成角、载瘤动脉是否通畅及再狭窄率等情况。支架段血管行光镜和扫描电镜检查,评价动脉瘤腔内血栓形成,内膜增生和内皮化情况。结果B组中,支架植入即刻血管造影显示２枚动脉瘤存在轻度内漏,３枚支架存在轻度成角现象;１２个月时随访,内漏均消失,１支载瘤动脉发生闭塞,３支载瘤动脉有轻度狭窄（＜５０％）。A组中,１支载瘤动脉闭塞,２支载瘤动脉轻度狭窄（＜５０％）。电镜检查所有支架内均有新生内膜形成,动脉瘤腔内均充满血栓。B组动物,１２个月时才完成完全内皮化过程,内皮细胞排列与血流动力学方向具有很强的相关性。结论应用Willis覆膜支架治疗犬CS动脉瘤方法学上可行。与直段血管相比,弯曲段血管内覆膜支架植入后,支架内皮化时间延长。     

可降解镁合金覆膜支架治疗兔颈总动脉侧壁型动脉瘤可行性研究

【摘要】 目的 评价可降解镁合金覆膜支架治疗兔颈总动脉侧壁型动脉瘤的可行性。方法 20只新西兰大白兔饲养1周后采用间断式外翻缝合法将右侧颈总动脉与静脉囊吻合，构建20枚颈总动脉侧壁型动脉瘤。72 h内分别实施可降解镁合金覆膜支架植入术和Willis覆膜支架植入术。术前、术后即刻、术后3、6、12个月作DSA造影检查，对比动脉瘤闭塞、内漏、血管痉挛、血管损伤、血栓事件、血管闭塞和狭窄等情况。结果 可降解镁合金覆膜支架和Willis覆膜支架各植入10枚，技术成功率为100%。支架植入术后即刻造影显示所有动脉瘤腔完全闭塞，载瘤动脉通畅，可降解镁合金覆膜支架组血管痉挛3例，Willis覆膜支架组血管痉挛1例；术后3、6、12个月复查造影显示动脉瘤完全消失，载瘤动脉通畅。 结论 可降解镁合金覆膜支架治疗兔颈总动脉侧壁型动脉瘤是可行的。
     

颈内动脉前壁动脉瘤支架结合弹簧圈栓塞术后再出血:病例报道

目的报道１例应用支架结合弹簧圈栓塞治疗颈内动脉前壁宽颈动脉瘤后发生早期再出血的病例。方法将球囊膨胀型血管内支架跨动脉瘤颈部位置并准确释放后,微导管超选进入动脉瘤内填塞弹簧圈。结果支架成功置入,完全覆盖瘤颈,动脉瘤得到大部栓塞（９０％以上）,载瘤动脉及毗邻的侧支血管保持通畅,患者术后恢复良好,但是术后１６d因动脉瘤再次破裂出血导致死亡。结论血管内支架结合弹簧圈栓塞治疗颈内动脉前壁宽颈动脉瘤是可行的,但应充分认识动脉瘤早期再次破裂出血的风险,短期随访及再治疗非常必要。     

应用Willis覆膜支架治疗脑池段动脉瘤的临床对照研究和长期随访结果

目的复杂性颈内动脉脑池段动脉瘤（ICA－CSA）治疗难度很高。本研究通过与弹簧圈填塞治疗疗效比较,探讨Willis覆膜支架治疗ICA－CSA的可行性。方法１９枚和１７枚ICA－CSA分别使用Willis覆膜支架植入（A组）和弹簧圈（B组）填塞治疗。即刻和随访血管造影评价动脉瘤复发,内漏和载瘤动脉狭窄情况。Kaplan－Meier生存分析曲线比较两组治疗动脉瘤的无复发率和载瘤动脉无再狭窄率。结果A组中,１３枚ICA－CSA植入支架,即刻造影完全闭塞,有５枚ICA－CSA存在少量内漏;B组中,７枚ICA－CSA弹簧圈填塞即刻达到完全和次完全闭塞,８枚达到大部填塞,２枚部分填塞。在两组中各发生１例急性血栓形成,１例弹簧圈填塞后发生再出血。A组随访造影显示１６枚ICA－CSA完全闭塞,２支载瘤动脉有轻度狭窄。Kaplan－Meier曲线分析表明术后１８个月两组病例中分别有９３．３％和５０％动脉瘤治疗后无复发,分别有８７．５％和１００％载瘤动脉无狭窄。临床症状随访研究表明A组和B组病例中神经症状完全恢复分别为９例和９例,明显改善分别为３例和５例,无改变分别为２例和２例,恶化进展分别为１例和０例。结论应用Willis覆膜支架植入治疗复杂性ICA－CSA是一种可行的血管内治疗方法,但是对于载瘤动脉极其弯曲和重要侧支覆盖风险的情况下,覆膜支架技术不能作为第一选择。     

Exploration of the land potential for the production of biomass for energy in the Netherlands

The energy potential for energy crops and biomass residues in the Netherlands is assessed. The analysis explores the possible use of land for biomass production in the future. Various government memorandums and analyses of the expected future land use in various sectors have served as the basis for the assessment of the supply of and the demand for land in the future. In this study the potential supply of agricultural land is based on expected productivity increments in agriculture and assumptions with respect to the future demand for agricultural products. Various future claims for infrastructure, forestry, urban areas and nature are subtracted from the expected supply. The net projected supply of land ranges from zero to 52 000 ha in 2000 to 110 000-250 000 ha in 2015. The supply of agricultural land depends however on a number of supra-national factors, such as the European agricultural policy, world market developments and the agricultural production in the countries in Eastern Europe. Uncertainties remain, therefore, and the projected supply of agricultural land should be considered as a possible scenario based on current trends. If the calculated land potential is used for energy crops like miscanthus and short rotation coppice, this land could contribute 0-10 PJ in 2000 and 27-59 PJ in 2015. Secondary biomass yields, such as those from forestry, agricultural residues, wood from prunings, etc., could contribute a further 34 PJ in 2000, decreasing to approximately 28 PJ in 2015. Taken together these potentials could satisfy 1-1.5% of the energy requirements of the Netherlands in 2000 and 1.5-2.5% in 2015, provided that energy farming is an economically feasible activity for farmers.     

Framework for the quantitative modelling of the European methodology for qualification of non-destructive testing

The European methodology for qualification of non-destructive testing has been adopted as the basis of inspection qualifications for nuclear utilities in many European countries. According to this methodology, the inspection qualification is based on a combination of technical justification and practical trials. The methodology is qualitative in nature, and it does not give explicit guidance on how the evidence from the technical justification and results from trials should be weighted. This article discusses the quantification of the methodology. A structured and quantified approach to combine evidence from technical justifications and practical trials would provide improved transparency in the qualification process. A Bayesian framework for the quantification process is presented and examples of possibilities to combine technical justification and trial results are given. The article also identifies the areas needing further development.     

Considerations for improving the reliability of the off-site powersupply for nuclear generating stations

It is argued that improvements in plant distribution system analysis, maintenance procedures, work control, definition of ownership, provision of detailed operational procedures and improved training can reduce loss of offsite power events. These improvements are not simple to implement in many cases, but as maximum grid loads grow and control and protective relaying become more complicated, it is essential that the processes to ensure adequate analysis, training, maintenance, and work control be in place     

射汽抽气器消声器气动声学性能研究

对Ｎ２００－１２．７／５３５／５３５型凝汽器射气器的气动声学性能进行了研究,分析了抽气器的气动噪声机理,由喷嘴喷注噪声、气流再生噪声、抽气器内部声波传播与衰减及出口噪声组成,并进行了工程计算,了抽气器消声器声学设计基础。     

Software Tool for the Implementation of the Methodology for Revitalization of High-Voltage Overhead Power Lines

In power systems, a large number of OPLs （overhead power lines） are more than 40 years old and some even exceed 50 years old. The key issue for power systems managers, public utilities companies and electrical engineers today concerns the manner in which available financial resources should be invested in these OPLs to provide the greatest impact on the power system as a whole and to address the OPLs that require urgent revitalization. This paper presents the application of the software tool RevOPL, developed using Microsoft Access utilizing the ＂methodology for revitalization of high-voltage OPLs＂. The aim is to present both the methodology and software to objectively evaluate the condition of an OPL and determine its remaining service life. The application of this software tool provides a proposal for the scheduling and scope of planned revitalization activities, which are obtained through the optimization of the technical characteristics while remaining within the available budget.     

Strategies for selection of thermo-chemical processes for the valorisation of biomass

Research on biomass conversion has been gaining a lot of interest as biomass is renewable and sustainable in nature. Products from biomass can be obtained by different methods amongst which thermo-chemical route has a very high potential. Biomass is generally available in a localised manner in varying quantities and qualities throughout the year and hence, region specific technologies have to be developed considering the end user requirement. Pyrolysis is a very versatile technique with the above considerations. The process parameters can be tweaked to necessity to produce more bio-oil or bio-char. Thermogravimetric analysis is essential for understanding the decomposition behaviour of the feedstock before the lab scale pyrolysis is carried out. Pyrolysis using several regional feedstocks has been carried out under nitrogen and hydrogen atmosphere and different biomass feedstocks were also liquefied using sub/supercritical solvents. This review aims to provide a comparison of the results obtained using various processes. This helps in the decentralised processing of biomass (dry biomass using pyrolysis and wet biomass by hydrothermal liquefaction) to produce bio-crude which can be upgraded to produce fuels/chemicals/petrochemical feedstocks in an environmental friendly manner.     

Advances in the implementation of PVD-based techniques for the preparation of metal catalysts for the hydrolysis of sodium borohydride

Sodium borohydride constitutes a safe alternative for the storage of hydrogen with a high gravimetric content. Catalytic hydrolysis of sodium borohydride permits on-demand hydrogen generation for multiple applications. In this field, the rational design of efficient metal catalysts deposited on structured supports is highly desirable. For most reactions, chemical methods are the most commonly used methods for the preparation of supported metal catalysts. Physical vapour deposition techniques are emerging as an alternative for the preparation of catalytic materials because of their multiple advantages. They permit the one-step deposition of catalysts on structured supports with controlled microstructure and composition, avoiding the multi-step procedures and the generation of hazardous by-products associated with chemical routes.In this short review, we will describe the available literature on the application of physical vapour deposition techniques for the preparation of supported metal catalysts for the hydrolysis of sodium borohydride. The effects of the deposition parameters on the properties of the catalytic materials will be discussed, and strategies for further improvement will be proposed. Here, we also present our new results on the study of nanoporous Pt catalysts that are prepared through the chemical dealloying of magnetron-sputtered Pt–Cu thin films for the hydrolysis of sodium borohydride. We discuss the capabilities of the technique to tune the microstructure from columnar to closed porous microstructures, which, coupled with dealloying, produces more active supported catalysts with lower noble metal loading. At the end, we briefly mention the application of PVD for the preparation of supported catalysts for the hydrolysis of ammonia borane, another hydrogen generating reaction of high interest nowadays.     

DF7型机车风泵控制电路的改进建议

针对DF7型机车柴油机卸载后风泵不能自动泵风的问题 ,全面分析了该车有关电路 ,指出了存在问题的原因 ,提出了解决问题的改进意见