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41.
摘要 目的:探讨自膨式支架辅助弹簧圈栓塞治疗颅内动脉瘤的疗效及安全性。方法:回顾性分析2014年1月-2019年1月我院采取自膨式支架辅助弹簧圈栓塞治疗颅内动脉瘤患者159例(A组)及采取单纯弹簧圈栓塞治疗颅内动脉瘤患者178例(B组),比较两种手术方法治疗颅内动脉瘤的手术时间、术后住院时间、随访时间、手术相关并发症发生率并通过格拉斯哥(GOS)预后评分、Raymond分级比较2种治疗方法的安全性及有效性。结果:两组手术时间、术后住院时间、随访时间比较差异无统计学意义(P>0.05)。两组术后出血及缺血事件发生率差异有统计学意义(P<0.05),脑积水、肺炎发生率、致死率及致残率差异无统计学意义(连续校正后P=1)。术后1月内及术后12个月随访GOS评分,A组评分高于B组,差异具有统计学意义(P<0.05);术后1月内及术后12个月随访Raymond分级,A组优于B组,差异具有统计学意义(P<0.05)。结论:自膨式支架辅助弹簧圈栓塞治疗颅内动脉瘤栓塞效果明显且术后并发症少,对于颅内动脉瘤患者在弹簧圈栓塞基础上应用自膨式支架辅助可提高手术安全性及栓塞的疗效。  相似文献   
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This study investigates the mechanism by which transmyocardial drilling revascularization combined with heparinized basic fibroblast growth factor incorporated degradable stent implantation (TMDRSI) enhanced effects of bone marrow mesenchymal stem cells (BMSCs) transplantation against acute ischemic myocardial injury. After the mid‐third of left anterior descending artery was ligated, miniswine were divided into none‐treatment group (control, n = 6), BMSCs implantation group (C, n = 6), TMDRSI group (TS, n = 6) and TMDRSI and BMSCs implantation group (TSC, n = 6). Two channels of 3.5 mm diameter were established by a self‐made drill in the ischemic region, into which a stent was implanted for the TS and TSC groups. Autologous BMSCs were transplanted into the ischemic region in C group or around the channels in TSC group. Expression of von Willebrand factor, vascular endothelial growth factor, interleukin‐1β, transforming growth factor‐β3, cell proliferation and apoptosis, histological and morphological analyses, myocardial remodelling and cardiac function were evaluated at different time‐points. Six weeks after the operation, the above indices were significantly improved in TSC group compared with others (P < 0.05), though C and TS groups also showed better results than the control group (P < 0.05). The new method was shown to have activated paracrine pathway of transplanted BMSCs, increased survival and differentiation of such cells, and enhanced effects of BMSCs transplantation on myocardial remodelling, which may provide a new strategy for cell therapies against acute ischemic myocardial injury.  相似文献   
44.
Fluorophores-modified nanoparticles comprised of poly(γ-glutamic acid)-phenylalanine (γ-PGA-Phe-633) and ovalbumin (OVA-750) termed NPs-633/OVA-750 were prepared to assess their biodistribution using an in vivo fluorescence imager. Dynamic light scattering measurements indicated that NPs-633/OVA-750 were about 200 nm in diameter. The release of encapsulated OVA from NPs-633 in PBS was negligible (~10%) for a week. When subcutaneously injected, the localization period of OVA-750-encapsulated into NPs-633 at the site of injection (SOI) was much longer than that of free OVA-750, but was shorter as compared to a mixture with aluminum hydroxide. The NPs-633 disappeared at the SOI and major organs within 1 month after administration. Moreover, intravenously and intraperitoneally administered NPs-633 were mainly observed at the liver, and there was more rapid clearance from all organs as compared with non-biodegradable NPs. These fast clearance and degradation characteristics of γ-PGA-Phe NPs will be important not only for avoiding undesired adverse effects, but also for inducing a strong vaccine effect.  相似文献   
45.
摘要 目的:探讨血管内支架介入成形术对老年缺血性脑血管病(ICVD)患者的神经功能、动脉血流速度及预后的影响。方法:选取2018年3月~2019年4月期间我院收治的117例老年ICVD患者作为研究对象,根据随机数字表法分为对照组(n=58)和研究组(n=59),其中对照组患者予以保守药物治疗,研究组患者予以血管内支架介入成形术治疗,比较两组患者疗效、神经功能、动脉血流速度、预后及并发症情况。结果:研究组治疗6个月后的临床总有效率为91.53%(54/59),高于对照组的72.41%(42/58)(P<0.05)。两组患者治疗后1个月、治疗后3个月、治疗后6个月美国国立卫生研究院卒中量表(NIHSS)评分均下降(P<0.05),且研究组低于对照组(P<0.05)。两组患者治疗后6个月大脑中动脉、基底动脉、颈内动脉血流速度均升高(P<0.05),且研究组高于对照组(P<0.05)。两组患者治疗后1个月、治疗后3个月、治疗后6个月改良Rankin量表(mRS)评分呈下降趋势(P<0.05),且研究组低于对照组(P<0.05)。两组患者并发症发生率对比未见统计学差异(χ2=2.261,P=0.133)。结论:老年ICVD患者经血管内支架介入成形术治疗后的疗效显著,可有效改善患者神经功能、动脉血流速度及预后,且不增加并发症发生率,具有较高的临床应用价值。  相似文献   
46.
Drug‐eluting stents (DES) were developed to combat the problem of in‐stent restenosis, and evaluating the biological activity from DES systems is critical for its safety and efficacy. To test the cytotoxicity of nitric oxide (NO) donor‐containing polymers for their potential use in DES applications, S‐nitrosoglutathione (GSNO) or in combination with poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) in an aqueous polymeric solution (PVA/PVP/GSNO) was investigated using Balb/c 3T3 and Rabbit arterial smooth muscle (RASM) cells. The sensitivity of 3T3 cells to the cytotoxicity effects induced by GSNO was higher than that of RASM cells, while RASM cells were more susceptible to alterations in membrane permeability. Cell growth assays showed that GSNO and PVA/PVP/GSNO induced antiproliferative effects in RASM cells. Moreover, the presence of polymers can reduce the cytotoxicity and enhance the antiproliferative effects of GSNO. Dose‐dependent inhibition of platelet aggregation was similar for both PVA/PVP/GSNO (EC50 of 3.4 ± 2.3 µM) and GSNO (EC50 of 2.8 ± 1.1 µM) solutions. Platelet adhesion assays showed that the inhibition caused by GSNO (EC50 of 5.0 mM) was dependent on the presence of plasma. These results demonstrate that the methodology adopted here is suitable to establish safety margins and evaluate the antithrombotic potential and antiproliferative effects of NO‐eluting biomaterials and polymeric solutions for the new cardiovascular devices, and also to emphasize the importance of using more specific cell lines in these evaluations. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
47.
Background: Endovascular angioplasty and stent placement is currently the most frequent treatment for iliac artery occlusive disease. However, despite a successful endovascular procedure, some patients do not experience symptomatic improvement and satisfaction with their care. This study seeks to identify patient-related factors associated with lack of symptomatic improvement after endovascular iliac artery treatment in male veterans.Methods: Retrospective review of patients treated with endovascular methods for iliac artery occlusive disease between January 2008 and July 2012 at VA Connecticut Healthcare System. Symptomatic improvement on the first post-operative visit was evaluated, with bilateral treatments counted separately.Results: Sixty-two patients had 91 iliac arteries treated with angioplasty and stent placement. Forty-seven (52 percent) legs had critical limb ischemia, and 77 (85 percent) had at least two-vessel distal runoff. Angiographic success was 100 percent. Patient-reported symptomatic improvement at the first post-operative visit was 55 percent (50/91). Lack of symptomatic improvement correlated with older age (OR 1.09 [1.03-1.17], p = 0.008), presence of critical limb ischemia (OR 3.03 [1.09-8.65], p = 0.034), and need for additional surgical intervention (OR 5.61 [1.65-17.36], p = 0.006). Survival, primary and secondary patency, and freedom from restenosis were comparable between patients who reported symptomatic improvement and those who did not.Conclusions: Despite angiographically successful revascularization, patients who are older or have critical limb ischemia who are treated with isolated endovascular iliac artery intervention are more likely to require additional interventions and less likely to experience symptomatic improvement. These patients may need more extensive infra-inguinal revascularization than isolated iliac angioplasty and stent placement, despite a preserved ankle-brachial index. Quality of life needs to be measured with formal instruments after iliac artery endovascular treatment, especially to determine long term outcomes.  相似文献   
48.
Recent clinical studies of the percutaneous transvenous mitral annuloplasty (PTMA) devices have shown a short-term reduction of mitral regurgitation after implantation. However, adverse events associated with the devices such as compression and perforation of vessel branches, device migration and fracture were reported. In this study, a finite element analysis was carried out to investigate the biomechanical interaction between the proximal anchor stent of a PTMA device and the coronary sinus (CS) vessel in three steps including: (i) the stent release and contact with the CS wall, (ii) the axial pull t the stent connector and (iii) the pressure inflation of the vessel wall. To investigate the impact of the material properties of tissues and stents on the interactive responses, the CS vessel was modelled with human and porcine material properties, and the proximal stent was modelled with two different Nitinol materials with one being stiffer than the other. The results indicated that the vessel wall stresses and contact forces imposed by the stents were much higher in the human model than the porcine model. However, the mechanical differences induced by the two stent types were relatively small. The softer stent exhibited a better fatigue safety factor when deployed in the human model than in the porcine model. These results underscored the importance of the CS tissue mechanical properties. Vessel wall stress and stent radial force obtained in the human model were higher than those obtained in the porcine model, which also brought up questions as to the validity of using the porcine model to assess device mechanical function. The quantification of these biomechanical interactions can offer scientific insight into the development and optimisation of the PTMA device design.  相似文献   
49.
The objectives of this work were to develop biodegradable trays from cassava starch, sugarcane fibers and Na-montmorillonite (Na-MMT) using a baking process and to study the effects of these components on the microstructure and physicochemical and mechanical properties of the trays. All formulations resulted in well-shaped trays with densities between 0.1941 and 0.2966 g/cm3. The addition of fibers and Na-MMT resulted in less dense and less rigid trays. As observed in the water sorption isotherms, the increase in the equilibrium moisture content was more pronounced when the samples were stored at RH (relative humidity) above 75%. The foams had high water absorption capacities (>50%) when immersed in water (1 min). The studied processing conditions resulted in good nanoclay dispersion, leading to the formation of an exfoliated structure. The trays developed in this study represent an alternative for the packaging of foods with low water contents.  相似文献   
50.
Starch trays and plates were prepared from native corn starch and corn starch cross-linked with glyoxal at different concentrations (0.126, 0.269, 0.271, 0.468 g/kg) using a foam baking process. The effect of cross-linking on baking parameters, including density, colour, water absorption, and tensile and flexural properties, was determined. Also, the morphologies of the trays were examined using a scanning electron microscope. Cross-linking considerably reduced the baking time, density and water absorption of the trays. Trays made from starch cross-linked with 0.126 and 0.269 g/kg glyoxal presented the best properties, with a homogenous microstructure and smooth surface quality. These trays had the lowest density (0.27 g/cm3) and had approximately 53% reduction in water absorption. Moreover, both the tensile and flexural strain of these foams was significantly higher than other foams.  相似文献   
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