新型国产镍钛合金封堵器封堵犬左心耳实验研究

【摘要】 目的 评估新型国产镍钛合金封堵器封堵犬左心耳的临床可行性和有效性。方法 选择清洁级健康成年杂种犬14只,采用自主研制的新型国产镍钛合金左心耳封堵器,经股静脉途径穿刺房间隔封堵左心耳。分别于术后即刻、1个月、3个月通过解剖、经食管超声心动图（TEE）检查等方法观察封堵效果。结果 14只实验犬中11只成功植入封堵器（其中2例因术中封堵器大小不合适,回收后再次植入成功）,2例房间隔穿刺时穿刺针误入心包引起心包积液而终止手术,1例术后随访发现封堵器脱入左心室,无其它手术并发症。术后各时间点分别处死实验犬,术后1个月大体观察见封堵器表面覆盖稀疏细胞,其上有内皮细胞,未见血栓及赘生物。术后3个月TEE检查见封堵器形态、位置良好,左心耳被完全封堵,左心房内无血栓形成;大体解剖见封堵器表面完全被内皮细胞覆盖,肝、肾、脾脏无血栓栓塞或梗死灶。结论 新型国产镍钛合金封堵器经导管封堵左心耳完全可行,中期效果理想。

     

左盘无铆型卵圆孔未闭封堵器的实验研究

【摘要】 目的 评价新型左盘无铆型卵圆孔未闭（PFO）封堵器经导管植入的可行性、安全性和有效性,为临床研究提供实验依据。方法 取20只健康成年犬,经皮房间隔卵圆窝穿刺、球囊扩张术建立犬PFO模型。将20只犬分为实验组（植入左盘无铆型PFO封堵器）和对照组（植入双铆型PFO封堵器）,每组10只。术后1、2、3和6个月分别通过对心脏大体标本、光镜、电镜检查,评价新型封堵器植入后内皮化过程,观察有无残余分流、血栓形成等并发症。结果 20只犬均成功进行了房间隔卵圆窝穿刺和球囊扩张术,右房造影可见对比剂由右房进入左房,成功建立了犬PFO模型。 实验组左盘无铆型PFO封堵器植入成功率为10/10,对照组成功率为9/10。19只犬术后1、2、3和6个月分别取出心脏大体标本进行观察,结果显示两组PFO封堵器的位置均无移位,无合金丝断裂,封堵器表面未见血栓形成和赘生物附着。术后1个月实验组封堵器双侧盘面可见薄层透亮组织覆盖,病理和电镜检查证实为纤维组织和内皮细胞,盘面无血栓和赘生物。至术后6个月,封堵器表面组织逐渐增厚,封堵器边缘与周围心脏组织融合。术后1个月对照组封堵器左侧盘面除中央铆钉外可见纤维组织和内皮细胞覆盖,术后6个月1只犬的左盘铆钉上仍无组织覆盖。结论 新型左盘无铆型PFO封堵器设计科学,与双铆型PFO封堵器相比较,完全内皮化的时间缩短,可有效的封堵PFO,具有良好的临床应用前景。
     

经导管堵闭犬左心耳对左房及毗邻解剖结构的影响

目的观察用自制新型左心耳封堵器堵闭犬左心耳后对左房及毗邻解剖结构的影响。方法用自行研制的新型左心耳封堵器经导管封堵２０只犬的左心耳。分别于术前和术后行经胸心脏超声检查，测量左房内径和容积，以及左上肺静脉血流速度和左房室瓣血流速度；并于术后行左心耳造影及左冠状动脉造影。结果１４只犬成功植入封堵器。术后经胸超声及造影检查见封堵器无移位，左心耳完全堵闭，封堵器植入后左房内径和容积，以及左上肺静脉血流速度和左房室瓣血流速度无明显变化，左冠状动脉回旋支正常显影。结论用自行研制的新型左心耳封堵器堵闭犬左心耳不影响左房以及毗邻解剖结构的功能，此方法安全可行     

纳米膜单铆型室间隔缺损封堵器动物实验研究

【摘要】 目的 在室间隔缺损（VSD）犬模型中评价新型纳米膜单铆型VSD封堵器经导管植入的可行性、安全性和有效性,为临床应用提供实验依据。方法 取健康成年犬26只,在开胸X线导引下通过右心室游离壁穿刺室间隔方法制备VSD模型;分为实验组（n＝13,植入纳米膜单铆型VSD封堵器）和对照组（n＝13,植入镍钛合金双铆型VSD封堵器）。术后1、2、3、6个月分别通过心脏大体标本、光镜、电镜检测及血镍离子浓度测定等评价新型封堵器植入后内皮化过程,观察有无残余分流、血栓形成等并发症。 结果 对26只犬成功建立开胸小切口VSD模型。实验组纳米膜单铆型VSD封堵器植入成功率为100%,对照组镍钛合金双铆型VSD封堵器植入成功率为91.7%。术后1、2、3、6个月分别取出25只犬心脏大体标本,观察显示两组封堵器位置均无移位,无合金丝断裂,盘面未见血栓形成和赘生物附着。术后1个月实验组封堵器双侧盘面可见薄层透亮组织覆盖,病理和电镜检查证实为纤维组织和内皮细胞;至术后6个月,盘面组织逐渐增厚,封堵器边缘与周围心脏组织融合。结论 纳米膜单铆型VSD封堵器设计科学,与镍钛合金双铆型VSD封堵器相比并发症少,完全内皮化时间缩短,可有效封堵VSD,具有良好的临床应用前景。     

LACBES左心耳封堵器及动物实验可行性研究

【摘要】 目的 介绍一种自主研究开发的LACBES左心耳封堵器,探讨其封堵左心耳的可行性。 方法 选取8只健康杂种犬,经股静脉途径应用LACBES封堵器封堵左心耳,术后测量封堵器压缩比例,造影定性评估残余分流;术前术后监测左心房压,分析左心耳封堵后对左心房压的即时影响。结果8只实验犬均成功植入LACBES左心耳封堵器,封堵器压缩比例为10%～15%。1只封堵术后有少量残余分流。2只术后死亡与操作相关,原因分别为封堵器移位及股动脉穿刺部位血肿,无器械相关死亡发生。术后即刻左心房收缩压升高,由术前（25.4±2.8） mmHg升至（27.5±3.4） mmHg（P＜0.05）,15 min后恢复至（25.3±2.8） mmHg。结论 LACBES封堵器封堵左心耳即刻成功率高,残余分流率低,左心房收缩压短暂升高,器械相关并发症低,有望应用于临床。
     

一种建立实验犬经皮左心耳封堵途径的方法

【摘要】 目的 验证一种建立实验犬经皮左心耳封堵途径方法的安全性及可行性。方法 12只实验犬房间隔穿刺后在不同体位左房造影后测量左心耳颈部直径,沿导丝送入输送封堵器的鞘管至左房中部,沿鞘管送入猪尾导管至左心耳内,沿猪尾导管推送输送长鞘进入左心耳内,退出猪尾导管经长鞘管造影观察鞘管在左心耳内的位置。术后1 h行心电图及经胸超声检查,即刻处死5只实验犬,取心脏观察房间隔穿刺位置、左房及左心耳内损伤情况。其余犬术后1 h及2周经胸超声心动图检查,随访1个月。结果 术中1只犬因心脏压塞死亡。8只犬在RAO30° ＋ CRA20°造影可以清楚显示左心耳形态,3只在RAO30°,1只在RAO30° ＋ CAU20°清楚显示左心耳形态,测量左心耳颈部直径为 （13.6 ± 5.2）mm,输送长鞘管均成功送入左心耳远端,无气栓、血栓、心脏压塞,2只穿刺点血肿,经加压包扎血肿吸收。术后即刻处死犬取心脏观察心包腔内未见血性液体,1只犬左房后壁轻度血肿, 2只左心耳上缘内膜轻度损伤可见血肿,手术操作时间（58 ± 12）min,透视时间（10.1 ± 2.5）min。其余犬术后及2周经胸超声随访无心包积液。随访1个月无猝死、卒中、感染。结论 应用本方法可安全有效的建立输送左心耳封堵器至左心耳内的途径。
     

国产房间隔缺损堵塞装置内皮化的实验研究

目的评价国产房间隔缺损(ASD)堵塞装置的内皮化.方法选用乳猪6头(平均体重7.5 kg),利用穿刺针和Rashkind球囊房隔造口术,建立大小不等ASD动物模型;选择适当大小的国产ASD堵塞装置进行封堵;术后1、3和6个月分别将小猪处死(每次2只),取堵塞装置行扫描电镜检查.结果术后1个月,装置表面被胶原纤维所覆盖,装置边缘见散在内皮细胞;术后3个月,装置表面大部分被内皮细胞所覆盖,伞尖表面光滑,无内皮细胞覆盖;术后6个月,装置表面完全被内皮细胞所覆盖,伞尖表面光滑并有内皮细胞上爬.结论国产ASD堵塞装     

左心耳封堵术MSCT三维成像测量可行性分析和临床应用

【摘要】 目的 采用心电门控多层螺旋CT（MSCT）三维成像技术重建心房颤动（AF）患者左心耳并进行测量,探讨其在经皮左心耳封堵术（PCLAA）中应用的可行性和临床价值。方法 入选AF患者27例,年龄43～80岁,平均（67.3±11.5）岁;非瓣膜性AF 25例,瓣膜性AF 2例。15例完成PCLAA术。术前行心电门控MSCT检查,通过AW4.4后处理工作站重建左心耳三维结构,空间向量测量左心耳开口长短径及深度,与术中经食管超声心动图（TEE）测量作比较,选择合适尺寸左心耳封堵器及植入位置,植入左心耳颈部。术后3个月TEE复查左心耳和（或）MSCT三维重建。结果 AW4.4后处理工作站重建下,外测法测量左心耳开口长径与封堵器最终选择有显著相关性（r=0.968）,差异无统计学意义（P＞0.05）;内侧法与封堵器最终选择有相关性（r=0.897）,差异无统计学意义（P＞0.05）。15例手术患者随访3个月,TEE或CT三维重建复查均未见血流渗漏。结论 心电门控MSCT三维成像技术能够重建AF患者左心耳三维结构,为PCLAA术前提供封堵器植入重要数据,也为术后随访提供可靠依据,具有临床可行性及应用价值。

     

左心耳封堵器临床研究进展

【摘要】 心房颤动是常见心律失常,是老年人缺血性脑卒中的主要原因之一。左心耳是非瓣膜性房颤（NVAF）形成血栓的主要部位。研究表明封堵左心耳可有效地减少NVAF患者缺血性脑卒中发作,其疗效不亚于华法林预防治疗作用。理想的左心耳封堵器是完成左心耳封堵的关键因素。经过数十年研究,目前临床上常用的左心耳封堵器有Watchman封堵器、ACP封堵器,还有部分封堵器处于临床前试验研究阶段。该文就目前左心耳封堵器研究和临床应用现状作一简要综述。
     

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。     

Destination: Perfection

The objectives of the perfect power project include: 1) the achievement of system-wide perfect power and demonstration of its technological viability; 2) 50% peak demand reduction capability via on-site generation when called upon by ComEd/PJM; 3) deferral of ComEd planned substation upgrades due to the demand reduction achieved; 4) demonstration of the economic value of perfect power, specifically the avoidance of outage costs and the introduction of significant savings and revenue from providing ancillary services; and 5) a design that can be replicated to any municipality-sized system where customers can participate in electric power market opportunities. In addition, the IIT team seeks to fulfill the mission of the university as set forth by President John L. Anderson, "IIT will be internationally recognized in distinctive areas of education and research, using as its platform the global city of Chicago, driven by a focus on professional and technology oriented education, and based on a culture of innovation that embraces bold and transformational ideas." Transforming the IIT power delivery infrastructure to achieve perfect power is a bold idea that will require a never-ending series of innovations. We have embraced the vision of the GEI and we look forward to sharing our progress with the power and energy community in the years to come.     

Mission: Reliability

Power system "operating reliability" is at the core of responsibilities that have been entrusted by French law to the Reseau de Transport d'Electricite (RTE), in its capacity as France's transmission system operator (TSO). The Power System Reliability Audit Mission is responsible for two main complementary activities: 1) carrying out power system reliability audits and 2) drafting of a yearly power system reliability report. In this section we present the principles, on which the control of system reliability is based, the procedure for creating the yearly reliability report, the procedure for the elaboration of the reliability audit plan, and the procedures governing the reliability audits.     

A-Si:H buffer in a-SiGe:H solar cells

Profiled a-SiGe:H-buffer layers between the doped and the absorption layers of amorphous silicon germanium (a-SiGe:H) solar cells are routinely used to avoid bandgap discontinuities and high-defect densities at the p/i- and i/n interface. Here, we present a much simpler approach replacing the profiled a-SiGe:H-buffer layers at both interfaces by a-Si:H-buffer layers. It is demonstrated that for a-SiGe:H solar cells (thickness of the E_G=1.5 eV part is 54 nm) these structures yield similar open circuit voltage V_OC and fill factor (FF) compared to the bandgap profiled layer at the same short circuit current density j_SC. The influence of thickness, optical bandgap and position of the buffer layers on the solar cell performance is investigated.     

Light Scattering in Pigmented Coatings:: Experiments and Theory

Small silica particles uniformly coated by a shell of titania, were produced by wet chemical methods. The pigments were dispersed in polymeric binders and were applied as paints to glass substrates. Total reflectance and transmittance were determined by integrating sphere measurements. Luminous and solar reflectance of paints containing the novel pigments were comparable with paints containing commercial titania. The spectral transmittance and reflectance of the paints were modelled by a four-flux radiative transfer theory. Theory and experiment could be brought into good agreement, if it was assumed that the particles were slightly porous. The studied pigments may find applications in sunscreens or in foils for daylighting and radiative cooling.     

Microcrystalline-phase p-type a-Si:O:H windows prepared by Cat-CVD

Different amounts of oxygen, boron-doped hydrogenated amorphous silicon (a-Si:H) and hydrogenated microcrystalline silicon (μc-Si:H) deposition were carried out using catalytic chemical-vapor deposition (Cat-CVD) process. Pure silane (SiH₄), hydrogen (H₂), oxygen (O₂), and diluted diborane (B₂H₆) gases were used at the deposition pressure of 0.1–0.5 Torr. The tungsten catalyst temperature (T_fil) was varied from 1700 to 2100 °C. Sample transmittance measurement shows an optical-band gap (E_gopt) variation from 1.45 to 2.1 eV X-ray diffraction (XRD) spectra have revealed silicon microcrystalline phases for the samples prepared at the temperature greater than T_fil1900 °C. For the used silicon oxide deposition conditions, no strong tungsten filament degradation was observed after a number of sample preparations.