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Argon reduces microglial activation and inflammatory cytokine expression in retinal ischemia/reperfusion injury 认领 被引量:1
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作者 Ulrich Goebel Stefanie Scheid +4 位作者 Sashko Spassov Nils Schallner Jakob Wollborn Hartmut Buerkle Felix Ulbrich 《中国神经再生研究:英文版》 SCIE CAS 2021年第1期192-198,共7页
We previously found that argon exerts its neuroprotective effect in part by inhibition of the toll-like receptors(TLR)2 and 4.The downstream transcription factors signal transducer and activator of transcription 3(STA... We previously found that argon exerts its neuroprotective effect in part by inhibition of the toll-like receptors(TLR)2 and 4.The downstream transcription factors signal transducer and activator of transcription 3(STAT3)and nuclear factor kappa B(NF-κB)are also affected by argon and may play a role in neuroprotection.It also has been demonstrated that argon treatment could mitigate brain damage,reduce excessive microglial activation,and subsequently attenuate brain inflammation.Despite intensive research,the further exact mechanism remains unclear.In this study,human neuroblastoma cells were damaged in vitro with rotenone over a period of 4 hours(to mimic cerebral ischemia and reperfusion damage),followed by a 2-hour post-conditioning with argon(75%).In a separate in vivo experiment,retinal ischemia/reperfusion injury was induced in rats by increasing intraocular pressure for 1 hour.Upon reperfusion,argon was administered by inhalation for 2 hours.Argon reduced the binding of the transcription factors signal transducer and activator of transcription 3,nuclear factor kappa B,activator protein 1,and nuclear factor erythroid 2-related factor 2,which are involved in regulation of neuronal damage.Flow cytometry analysis showed that argon downregulated the Fas ligand.Some transcription factors were regulated by toll-like receptors;therefore,their effects could be eliminated,at least in part,by the TLR2 and TLR4 inhibitor oxidized phospholipid 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine(OxPAPC).Argon treatment reduced microglial activation after retinal ischemia/reperfusion injury.Subsequent quantitative polymerase chain reaction analysis revealed a reduction in the pro-inflammatory cytokines interleukin(IL-1α),IL-1β,IL-6,tumor necrosis factorα,and inducible nitric oxide synthase.Our results suggest that argon reduced the extent of inflammation in retinal neurons after ischemia/reperfusion injury by suppression of transcription factors crucial for microglial activation.Argon has no known side effects o 展开更多
关键词 ARGON ischemia/reperfusion injury MICROGLIA NEUROINFLAMMATION NEUROPROTECTION noble gas SH-SY5Y toll-like receptor transcription factor
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肋片形式对Hampson型换热器流动换热特性影响 认领
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作者 王悠悠 文键 +2 位作者 张星 王斯民 厉彦忠 《真空与低温》 2021年第2期159-164,共6页
微型Hampson节流制冷机广泛应用于电子器件冷却,其换热器效率对制冷机的性能有着决定性作用。采用真实氩气物性参数,对Hampson型螺旋肋片管换热器进行了稳态三维数值模拟研究,研究了环形、螺旋形、锯齿螺旋形、扭曲锯齿螺旋形四种肋片... 微型Hampson节流制冷机广泛应用于电子器件冷却,其换热器效率对制冷机的性能有着决定性作用。采用真实氩气物性参数,对Hampson型螺旋肋片管换热器进行了稳态三维数值模拟研究,研究了环形、螺旋形、锯齿螺旋形、扭曲锯齿螺旋形四种肋片形式的肋片管换热器的流动换热性能。结果表明:相较于螺旋形肋片,扭曲锯齿形肋片能显著提高近壁面工质流速并减小流动死区,使Eu数上升119.16%~121.14%,Nu上升38.98%~40.35%,综合强化换热效果最好。环形和锯齿形肋片会使壳程Eu分别上升-3.53%~-3.97%和94.82%~95.74%,同时会使Nu分别增大0.27%~0.80%和29.62%~30.97%,PEC准则数均大于1,综合效果有所提升。 展开更多
关键词 微型Hampson节流制冷机 肋片管换热器 数值模拟 AR
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Role of argon plasma coagulation in treatment of esophageal varices 认领
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作者 Ying Song Yuan Feng +6 位作者 Li-Hui Sun Bo-Jiang Zhang Hong-Juan Yao Jing-Gui Qiao Shu-Fen Zhang Ping Zhang Bin Liu 《世界临床病例杂志》 SCIE 2021年第3期521-527,共7页
With the development of endoscopic therapy,argon plasma coagulation(APC)has been widely used by endoscopists.It has many advantages,such as simple to operate,low cost,and minimal invasiveness.Because of its capability... With the development of endoscopic therapy,argon plasma coagulation(APC)has been widely used by endoscopists.It has many advantages,such as simple to operate,low cost,and minimal invasiveness.Because of its capability of lesion ablation and hemostasis,APC has several indications in the gastrointestinal tract.One of them is esophageal varices.The aim of this review is to summarize the research on APC in this field to provide a reference for clinical practice. 展开更多
关键词 Esophageal varices Argon plasma coagulation Clinical practice Endoscopic therapy Gastrointestinal tract Minimally invasive
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Management of Barrett’s esophagus with dysplasia refractory to radiofrequency ablation 认领
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作者 Kara L Raphael Arvind J Trindade 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第17期2030-2039,共10页
Radiofrequency ablation(RFA)is very effective for eradication of flat Barrett’s mucosa in dysplastic Barrett’s esophagus after endoscopic resection of raised lesions.However,in a minority of the time,RFA may be inef... Radiofrequency ablation(RFA)is very effective for eradication of flat Barrett’s mucosa in dysplastic Barrett’s esophagus after endoscopic resection of raised lesions.However,in a minority of the time,RFA may be ineffective at eradication of the Barrett’s mucosa.Achieving complete eradication of intestinal metaplasia can be challenging in these patients.This review article focuses on the management of patients with dysplastic Barrett’s esophagus refractory to RFA therapy.Management strategies discussed in this review include optimizing the RFA procedure,optimizing acid suppression(with medical,endoscopic,and surgical management),cryotherapy,hybrid argon plasma coagulation,and EndoRotor resection. 展开更多
关键词 Low-grade DYSPLASIA HIGH-GRADE DYSPLASIA Radiofrequency ablation CRYOTHERAPY EndoRotor Hybrid ARGON PLASMA COAGULATION ARGON PLASMA COAGULATION
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Bubbling to Jetting Transition during Argon Injection in Molten Steel 认领
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作者 Miguel A. Barron Joan Reyes Dulce Y. Medina 《世界工程和技术(英文)》 2020年第4期605-616,共12页
Bubbling to Jetting Transition is of the outmost importance in metallurgical processes given that the flow regime influences the refining rates, the refractory erosion, and the blockage of injection nozzles. Bubbling ... Bubbling to Jetting Transition is of the outmost importance in metallurgical processes given that the flow regime influences the refining rates, the refractory erosion, and the blockage of injection nozzles. Bubbling to jetting transition during subsonic bottom injection of argon in molten steel is studied here. The effect of the molten steel height, the injection velocity, the nozzle diameter, and the molten steel viscosity on the jet height and the bubbling to jetting transition is numerically analyzed using Computational Fluid Dynamics. Five subsonic argon injection velocities are considered: 5, 25, 50, 100 and 150 m/s. Three values of the metal height are taken into account, namely 1.5 m, 2 m and 2.5 m. Besides, three values of the nozzle diameters are considered: 0.001 m, 0.005 m and 0.01 m. Finally, three values of the molten steel viscosity are supposed: 0.0067, 0.1 and 1 kg/(m<span style="font-family:Verdana;"><span style="white-space:nowrap;">·</span></span><span style="font-family:Verdana;">s). It is observed that for the argon-molten steel system</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the bubbling to jetting transition occurs for an injection velocity less than 25 m/s and that for the range of viscosities considered, the molten steel viscosity does not exert significant influence on the jet height and the bubbling to jetting transition. Due to the jet instability at subsonic velocities</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> a second transition, namely jetting to bubbling, is appreciated</span><span style="font-family:Verdana;">.</span> 展开更多
关键词 Argon Injection Bubbling to Jetting Transition CFD Injection Velocity Jet Height Molten Steel Nozzle Diameter
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饱和氩蒸气冷凝特性的分子动力学模拟 认领
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作者 王宝和 雷广平 王维 《河南化工》 CAS 2020年第1期14-18,共5页
采用分子动力学模拟方法,对饱和氩蒸气的冷凝特性进行了模拟研究。模拟结果表明,随着温度的升高,气-液界面厚度逐渐增大,冷凝系数有所降低。冷凝活化能随着温度的升高而增加,但增幅逐渐变小。冷凝系数与冷凝活化能之间的关系可以用Arrhe... 采用分子动力学模拟方法,对饱和氩蒸气的冷凝特性进行了模拟研究。模拟结果表明,随着温度的升高,气-液界面厚度逐渐增大,冷凝系数有所降低。冷凝活化能随着温度的升高而增加,但增幅逐渐变小。冷凝系数与冷凝活化能之间的关系可以用Arrhenius方程来描述。 展开更多
关键词 分子动力学 模拟 饱和蒸气 冷凝
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放射性惰性气体分离与分离材料研究进展 认领
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作者 熊顺顺 闫钊通 +5 位作者 刘博煜 刘强 吴晓楠 龚有进 杨楚汀 汪小琳 《核化学与放射化学》 CAS CSCD 北大核心 2020年第6期478-497,共20页
放射性惰性气体氙(133 Xe)、氪(85 Kr)与氩(37 Ar)是重要的气体裂变产物,主要产生于核电站反应堆、地下核试验、乏燃料后处理等人类核活动中。放射性惰性气体的快速高效分离、分析与检测在核军控核查、核环境监控、核燃料循环等领域中... 放射性惰性气体氙(133 Xe)、氪(85 Kr)与氩(37 Ar)是重要的气体裂变产物,主要产生于核电站反应堆、地下核试验、乏燃料后处理等人类核活动中。放射性惰性气体的快速高效分离、分析与检测在核军控核查、核环境监控、核燃料循环等领域中均有重要意义。利用固体多孔吸附材料在室温环境下从复杂环境气氛中选择性地将目标放射性惰性气体高效吸附分离出来是目前最简单与高效的方法。近些年发展的金属有机框架材料、多孔有机框架材料、多孔有机聚合物等新型多孔材料在惰性气体Xe与Kr的分离上已经展现出优异的性能与良好的应用前景。本文系统性地综述了放射性惰性气体(Xe、Kr、Ar)分离与分离材料的研究进展,并对未来研究趋势进行了展望。 展开更多
关键词 放射性惰性气体 吸附分离
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不同气氛加热过程中CeO2晶体结构的原位研究 认领
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作者 毛锡嵩 夏雪雯 +3 位作者 兰苑培 姜浪钊 蒋小勇 田翔宇 《中国稀土学报》 CAS CSCD 北大核心 2020年第4期483-489,I0002,共8页
以Ce(NO3)3·6H2O为原料,水热法制备纳米CeO2颗粒,将其在空气中高温焙烧多次获得稳定的CeO2。以稳定的CeO2作为研究对象,采用TG分析在不同气氛(Air/Ar)加热过程中CeO2的失重率,并结合原位XRD研究在此过程中CeO2的晶体结构变化。TG... 以Ce(NO3)3·6H2O为原料,水热法制备纳米CeO2颗粒,将其在空气中高温焙烧多次获得稳定的CeO2。以稳定的CeO2作为研究对象,采用TG分析在不同气氛(Air/Ar)加热过程中CeO2的失重率,并结合原位XRD研究在此过程中CeO2的晶体结构变化。TG结果显示,在Ar气气氛加热过程中CeO2具有较高的失重率,表明CeO2在此过程中产生了较多的氧空位。原位XRD结果显示,CeO2在不同气氛加热过程中一直保持良好的fcc萤石结构;且随着温度升高,CeO2晶格发生膨胀,晶格常数增大。在Ar气气氛加热过程中CeO2晶格常数的增长幅度略大于空气气氛中,也表明在该过程中产生了较多的氧空位,促使CeO2晶格进一步膨胀。在加热过程中CeO2的晶格膨胀受到温度和氧空位的同时影响,因此,使用原位技术研究CeO2的晶体结构时,需同时考虑温度及氧空位对晶格常数的影响。 展开更多
关键词 加热 Ar气 CEO2 晶格常数
Investigation into the transient flow characteristics of noble gas propellants using the pulsed inductive discharge in electric propulsion 认领
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作者 Yuguo CHENG Guangqing XIA 《中国航空学报:英文版》 SCIE EI CAS CSCD 2020年第9期2329-2341,共13页
The Pulsed Inductive Thruster(PIT)has the advantages of repeatable startup,no corruption and in-situ propellant feed.To study the flow expansion and circuit characteristics of PITs,the circuit-fluid model is developed... The Pulsed Inductive Thruster(PIT)has the advantages of repeatable startup,no corruption and in-situ propellant feed.To study the flow expansion and circuit characteristics of PITs,the circuit-fluid model is developed,and the high temperature thermodynamic and transport models are combined with the circuit-fluid model to predict the critical plasma parameters.The flow fields of initial mass of 2–8 mg and charge voltages of 10–14 k V are simulated.Comparison of the flow fields of argon and helium propellants suggests that,the flow field structures are similar.Slight differences exist on the magnitude of the density and magnetic field,caused by larger velocity in lighter atom case and difference on the ionization gap between adjacent ionization levels.Analysis of the circuit characteristics by the two-dimensional results indicates that the ratio of coil inductance to circuit inductance affects both the rise rate and phase of the plasma current,the larger the ratio,the greater the rise rate and the better the following characteristic.The calculations show that the magnetic energy obtained within the decoupling distance determines the overall performance the thruster can be obtained;self-induced field maintained by the thermal motion after the main pulse leads to the long attenuation process and difference on the total impulse when the angle of conical pylon is varied under constant coil dimension. 展开更多
关键词 Argon and helium propellants Circuit characteristics Circuit-fluid model Flow properties Pulsed inductive thruster
Improved Removal Efficiency of Submicron Inclusions in Non-oriented Silicon Steel during RH Process 认领
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作者 陈天颖 JIN Yan +3 位作者 CHENG Zhaoyang YUAN Zexi BI Yunjie 刘静 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2020年第6期1122-1127,共6页
To improve the removal efficiency of such submicron inclusions,we designed an argon blowing method for an RH facility based on mathematical simulations.The effect of the argon blowing on the liquid steel flow and the ... To improve the removal efficiency of such submicron inclusions,we designed an argon blowing method for an RH facility based on mathematical simulations.The effect of the argon blowing on the liquid steel flow and the movement of submicron inclusions was studied using the k-ε flow model coupled with the DPM model for inclusion movement based on fluid computational dynamics in FLUENT.It was found that a more uniform argon flow can be achieved in the up-leg snorkel with a new nozzle position and inner diameter,which resulted in a favorable up-lifting and mixing movement.The new design also increased the circulation rate of molten steel in the RH chamber.The increased turbulent kinetic energy and turbulent dispersing rate enhanced the collision probability of submicron inclusions,which results in an improved removal for 0.5-1 μm inclusions.The proposed RH facility could increase the removal rate of submicron inclusions from the original 57.1% to 66.4%,which improves the magnetic properties of non-oriented silicon steel. 展开更多
关键词 RH treatment argon blowing method model optimization submicron inclusions numerical simulation
氮氩气流量比对磁控溅射氮化钛薄膜微观结构的影响 认领
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作者 王槐乾 姜宏伟 +3 位作者 黄海亮 王方标 左桂鸿 郑友进 《电镀与涂饰》 CAS CSCD 北大核心 2020年第7期405-409,共5页
采用扫描电镜(SEM)和X射线衍射仪(XRD)研究了氮气流量(5、10、25、50 sccm)及氮氩气流量比(4∶1、3∶2、2∶3、1∶4)对磁控溅射TiN薄膜微观形貌和相组成的影响。结果显示,所得样品具有纳米级TiN薄膜的基本特征。当N2与Ar的总流量为5 sc... 采用扫描电镜(SEM)和X射线衍射仪(XRD)研究了氮气流量(5、10、25、50 sccm)及氮氩气流量比(4∶1、3∶2、2∶3、1∶4)对磁控溅射TiN薄膜微观形貌和相组成的影响。结果显示,所得样品具有纳米级TiN薄膜的基本特征。当N2与Ar的总流量为5 sccm,而它们的流量比为4∶1时,可以制得品质较好的蓝紫色TiN薄膜。 展开更多
关键词 氮化钛 磁控溅射 氮气 氩气 流量比 微观结构 颜色
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Effect of sintering temperature in argon atmosphere on microstructure and properties of 3D printed alumina ceramic cores 认领
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作者 He LI Yongsheng LIU +4 位作者 Yansong LIU Qingfeng ZENG Kehui HU Zhigang LU Jingjing LIANG 《先进陶瓷:英文版》 SCIE CSCD 2020年第2期220-231,共12页
Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D printing.The effects of sintering temperature on microstructure and physical and mechanical pro... Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D printing.The effects of sintering temperature on microstructure and physical and mechanical properties were investigated.The results show that the average particle size,shrinkage,bulk density,crystallite size,flexural strength,Vickers hardness,and nanoindentation hardness increased with the increase in sintering temperature,whereas the open porosity decreased with increasing sintering temperature.No change was observed in phase composition,chemical bond,atomic ratio,and surface roughness.For the sintered samples,the shrinkage in Z direction is much greater than that in X or Y direction.The optimum sintering temperature in argon atmosphere is 1350℃with a shrinkage of 3.0%,3.2%,and 5.5%in X,Y,and Z directions,respectively,flexural strength of 26.7 MPa,Vickers hardness of 198.5 HV,nanoindentation hardness of 33.1 GPa,bulk density of 2.5 g/cm^3,and open porosity of 33.8%.The optimum sintering temperature was 70℃higher than that sintering in air atmosphere when achieved the similar properties. 展开更多
关键词 sintering temperature argon atmosphere alumina ceramics MICROSTRUCTURE STEREOLITHOGRAPHY
膜回收系统在乙二醇装置中的运用 认领
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作者 徐勇 《广东化工》 CAS 2020年第24期112-114,共3页
乙二醇装置为控制循环气中乙烷、氩气等气体含量,将部分循环气排放至废热锅炉进行焚烧,在此股排放气内仍含有20%左右的乙烯,造成大量乙烯原料的损失。为此,装置增设膜回收系统对排放气内乙烯进行分离并回收。对膜回收系统运行状态影响... 乙二醇装置为控制循环气中乙烷、氩气等气体含量,将部分循环气排放至废热锅炉进行焚烧,在此股排放气内仍含有20%左右的乙烯,造成大量乙烯原料的损失。为此,装置增设膜回收系统对排放气内乙烯进行分离并回收。对膜回收系统运行状态影响因素进行分析,发现系统对乙烯气体最佳回收率达到96.75%,乙烯年回收量为1602吨,节省乙烯成本约1100万元。 展开更多
关键词 膜回收 乙二醇 乙烯 氩气
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氮泄漏进入空分装置主冷对氩系统的影响和对策 认领
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作者 黄震宇 《冶金动力》 2020年第9期26-27,共2页
对主冷内漏对空分特别是带氩空分装置的影响进行分析,提出带氩空分装置出现此类情况下的临时应急解决办法,取得了很好的实际效果。
关键词 氩气 主冷 内漏 应急处理
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饱和氩气体热力学性质的分子动力学模拟 认领
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作者 王宝和 雷广平 王维 《河南化工》 CAS 2020年第3期16-20,共5页
采用分子动力学模拟方法,对饱和氩气体的热力学性质进行了模拟计算。模拟结果表明,随着温度的升高,液相主体密度和饱和氩气体的摩尔体积逐渐降低,气相主体密度逐渐增大。维里方程法和RK方程法计算得到的饱和氩气体压力与实验结果基本一... 采用分子动力学模拟方法,对饱和氩气体的热力学性质进行了模拟计算。模拟结果表明,随着温度的升高,液相主体密度和饱和氩气体的摩尔体积逐渐降低,气相主体密度逐渐增大。维里方程法和RK方程法计算得到的饱和氩气体压力与实验结果基本一致。虚拟理想气体法及RK方程法计算得到的饱和氩气体逸度值及实验结值三者基本一致。 展开更多
关键词 分子动力学模拟 饱和汽体 压力 逸度
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氩气协同超细水雾抑制甲烷爆炸试验研究 认领
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作者 杨克 王壮 +2 位作者 邢志祥 周越 蒋军成 《中国安全科学学报》 CAS CSCD 北大核心 2020年第7期55-61,共7页
为加强超细水雾对甲烷爆炸的抑制效果,搭建小尺寸半封闭甲烷爆炸试验平台,开展氩气协同超细水雾抑制甲烷爆炸试验。通过单因素和曲面优化试验,测试氩气、超细水雾以及两者的协同作用对甲烷爆炸的抑制效果;从火焰特性、最大爆炸超压和平... 为加强超细水雾对甲烷爆炸的抑制效果,搭建小尺寸半封闭甲烷爆炸试验平台,开展氩气协同超细水雾抑制甲烷爆炸试验。通过单因素和曲面优化试验,测试氩气、超细水雾以及两者的协同作用对甲烷爆炸的抑制效果;从火焰特性、最大爆炸超压和平均升压速率3个方面探究氩气和超细水雾协同抑爆的优越性。结果表明:氩气和超细水雾协同抑制甲烷爆炸效果显著;随着氩气体积分数和超细水雾喷雾量的增加,火焰冲出管道的时间逐渐延长,最大爆炸超压和平均升压速率逐渐降低;其中氩气体积分数10%、超细水雾喷雾量4.2 m L的工况抑制效果最佳;甲烷最大爆炸超压较氩气和超细水雾单独作用下分别下降6.15和2.68 k Pa,说明氩气和超细水雾抑止甲烷爆炸具有协同效应。 展开更多
关键词 氩气 超细水雾 协同效应 甲烷 爆炸 抑制效果
The dynamics of a nanosecond gas discharge development with an extended slot cathode in argon 认领
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作者 N A ASHURBEKOV K O IMINOV +2 位作者 G S SHAKHSINOV M Z ZAKARYAEVA K M RABADANOV 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2020年第12期78-88,共11页
The article presents the results of an experimental study and numerical modelling for the formation and development dynamics of a high-voltage transverse nanosecond discharge generated by a slot cathode in an argon me... The article presents the results of an experimental study and numerical modelling for the formation and development dynamics of a high-voltage transverse nanosecond discharge generated by a slot cathode in an argon medium at a pressure range of 1–10 Torr. Numerical modelling was carried out under similar experimental conditions for the processes of formation and propagation of ionisation waves, electron density distribution, excited atom and average electron energy in the discharge gap, including the cavity inside the cathode. At a pressure of p=1 Torr, a classical version of a high-voltage discharge is demonstrated to take place with no penetration of the plasma into the cathode cavity and no observed hollow cathode effect. An increase in gas pressure to 5 Torr leads to a penetration of plasma into the cathode cavity with the formation of a cathodic potential drop(CPD) region. Electrons emitted from the side surfaces of the cavity pass through the CPD region without collisions, oscillate inside the cathode cavity;the hollow cathode effect is fully manifested. At р=10 Torr, the modelling results qualitatively coincide with the results at р=5 Torr;in this case, however, hardly any accelerated electrons are observed in the gap between the electrodes, due to their energetic relaxation both inside the cathode cavity and when exiting from it. In both cases, the plasma structure formed at the exit of the cathode cavity involves a concentration of charged particles an order of magnitude higher than that in the rest of the gap, leading to a self-limiting discharge current effect. The results of the numerical modelling are in good agreement with experimental data. 展开更多
关键词 nanosecond gas discharge numerical simulation ARGON excited atoms
Endoscopic mucosal ablation-an alternative treatment for colonic polyps:Three case reports 认领
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作者 Antonio Mendoza Ladd Joaquin Espinoza Cesar Garcia 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第45期7258-7262,共5页
BACKGROUND Endoscopic resection of non-invasive lesions is now the standard of care for lesions in the GI tract.However,resection techniques require extensive training,are not available in all endoscopy centers and ar... BACKGROUND Endoscopic resection of non-invasive lesions is now the standard of care for lesions in the GI tract.However,resection techniques require extensive training,are not available in all endoscopy centers and are prone to complications.Endoscopic mucosal ablation(EMA)is a combination of resection and ablation techniques and it may offer an alternative in the management of such lesions.CASE SUMMARY In this case series we report the successful treatment of three flat colonic polyps using the EMA technique.Two lesions were treatment naïve and 1 was a recurrence after an endoscopic mucosal resection.The sizes ranged from 2 to 4 cm.All three polyps were ablated successfully with no immediate or delayed complications.The recurrence rate at 1 year of follow up was 0%.CONCLUSION Based on this initial experience,we conclude that EMA is a safe and effective technique for the treatment of non-invasive colonic polyps when endoscopic resection techniques are not available. 展开更多
关键词 ENDOSCOPY Mucosal ablation Colon polyp Argon plasma coagulation ALTERNATIVE SAFE Case report
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柴油加氢装置循环氢纯度下降原因分析及对策 认领 被引量:1
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作者 王建军 《炼油技术与工程》 CAS 2019年第8期14-17,共4页
中国石油化工股份有限公司镇海炼化分公司3.0 Mt/a柴油加氢装置自开工以来循环氢纯度逐渐下降.通过对循环氢和补入氢(以下简称新氢)组成的对比发现,新氢中氩气含量较高,该组分随着运行时间增长存在累积过程,导致循环氢纯度逐渐下降.搭... 中国石油化工股份有限公司镇海炼化分公司3.0 Mt/a柴油加氢装置自开工以来循环氢纯度逐渐下降.通过对循环氢和补入氢(以下简称新氢)组成的对比发现,新氢中氩气含量较高,该组分随着运行时间增长存在累积过程,导致循环氢纯度逐渐下降.搭建模型分析研究热高分入口温度、冷高分入口温度对氩气溶解度及循环氢纯度的影响,确定了冷高分入口温度是影响循环氢纯度的主要工艺参数.综合上述分析,通过切换新氢来源(氩气体积分数小于0.3%)、降低冷高分入口温度两方面措施,提高了循环氢纯度,保证了加氢反应深度,解决了新氢中氩气造成柴油加氢装置循环氢纯度下降的问题. 展开更多
关键词 柴油加氢 循环氢 氢气 氩气 冷高分
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Efficacy and complications of argon plasma coagulation for hemorrhagic chronic radiation proctitis 认领 被引量:2
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作者 Qing-Hua Zhong Zhan-Zhen Liu +6 位作者 Zi-Xu Yuan Teng-Hui Ma Xiao-Yan Huang Huai-Ming Wang Dai-Ci Chen Jian-Ping Wang Lei Wang 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第13期1618-1627,共10页
BACKGROUND Chronic radiation proctitis (CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there i... BACKGROUND Chronic radiation proctitis (CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there is no literature to date showing any particularly appropriate therapeutic modality for each disease stage. Argon plasma coagulation (APC) is currently recommended as the firstchoice treatment for hemorrhagic CRP, however, its indication based on longterm follow-up is still unclear. On the hypothesis that the long-term efficacy and safety of APC are not fully understood, we reviewed APC treatment for patients with hemorrhagic CRP from a single center. AIM To assess the long-term efficacy and safety of APC for hemorrhagic CRP. METHODS This is a retrospective study of consecutive patients treated with APC for hemorrhagic CRP from January 2013 to October 2017. Demographics, clinical variables, and typical endoscopic features were recorded independently. Success was defined as either cessation of bleeding or only occasional traces of bloody stools with no further treatments for at least 12 mo after the last APC treatment. We performed univariate and multivariate analyses to identify factors associated with success and risk factors for fistulas. RESULTS Forty-five patients with a median follow-up period of 24 mo (range: 12-67 mo) were enrolled. Fifteen (33.3%) patients required blood transfusion before APC. Successful treatment with APC was achieved in 31 (68.9%) patients. The mean number of APC sessions was 1.3 (1-3). Multivariate analysis showed that APC failure was independently associated with telangiectasias present on more than 50% of the surface area [odds ratio (OR)= 6.53, 95% confidence interval (CI): 1.09- 39.19, P = 0.04] and ulcerated area greater than 1 cm^2 (OR = 8.15, 95%CI: 1.63- 40.88, P = 0.01). Six (13.3%) patients had severe complications involving rectal fistulation. The only factor significantly associated with severe complications was ulcerated area greater than 1 cm^2 (P = 0.035). CO 展开更多
关键词 ARGON plasma coagulation CHRONIC RADIATION PROCTITIS RADIATION proctopathy EFFICACY Safety
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