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991.
目的探索建立无血预充兔体外循环模型的方法。方法30只新西兰兔,采用右心房引流,右锁骨下动脉灌注的方法,建立兔体外循环模型,并监测转流前、中和后动脉血气变化。结果成功建立起无血预充兔体外循环模型。动脉血气各项指标结果满意。结论建立无血预充兔体外循环模型是可行的。 相似文献
992.
Sanghoon Shin Kwang-Joon Kim In-Jeong Cho Geu-Ru Hong Yangsoo Jang Namsik Chung Young Min Rah Hyuk-Jae Chang 《Yonsei medical journal》2015,56(5):1227-1234
Purpose
Primary vascular dysregulation (PVD) is a condition in which the response to cold temperature or external stimuli is abnormal. We investigated whether triflusal use results in amelioration of PVD symptoms and improvement of several related parameters compared with aspirin.Materials and Methods
Eighty-eight PVD patients (54% female, 56±8 years) were randomly selected to receive either triflusal (300 mg, b.i.d.) or aspirin (150 mg, b.i.d.) for a period of 6 weeks followed by crossover. PVD was defined as both red-blood-cell standstill in video-assisted microscopic capillaroscopy during cold stimulation using carbon dioxide gas and a score of more than 7 points in a validated questionnaire. Efficacy of treatment was assessed by 1) cold intolerance symptom severity (CISS) score, 2) finger Doppler indices, and 3) indocyanine green perfusion imaging.Results
The use of triflusal resulted in a greater improvement in CISS score (44.5±18.4 vs. 51.9±16.2; p<0.001) and in mean radial peak systolic velocity (69.8±17.2 vs. 66.1±16.4; p=0.011) compared to aspirin. Furthermore, significant differences were also observed in perfusion rates on indocyanine green perfusion imaging between triflusal and aspirin (45.6±25.8 vs. 51.6±26.9; p=0.020).Conclusion
Triflusal was more effective and demonstrated a more consistent impact on the improvement of symptoms and blood flow in patients with PVD than aspirin. 相似文献993.
复方黄芪袋泡饮改善慢性冠脉供血不足的研究 总被引:1,自引:0,他引:1
复方黄芪袋泡饮改善慢性冠脉供血不足的研究刘志泉*陈跃*李岩飞*丁煜*为寻找一种比传统扩血管药物更为有效的中西药复方制剂以改善冠脉血供,降低心绞痛和心肌梗塞的发生率,我们依据中西药理论,结合现代血液流变学和微循环的科研成果,研制了以黄芪、阿司匹林为主要... 相似文献
994.
F. Unger R. Schistek J. Hager I. Roller N. Nessler P. Oberwalder A. Benzer 《Artificial organs》1985,9(1):65-68
In the last decade, there have been many experiments with nonpulsatile blood pumps to perform functional heart replacement by biventricular assist devices. To determine if life is sustainable with nonpulsatile blood flow, two nonpulsatile blood pumps were implanted in the orthotopic position as an artificial heart after removal of the natural heart in extracorporeal circulation. In three preliminary experiments, the feasibility of total heart replacement with nonpulsatile implantable blood pumps was shown. 相似文献
995.
目的 观察体外冲击波疗法(ESWT)对膝骨关节炎(KOA)患者的下肢功能、安全性及关节软骨的影响。 方法 将符合纳入标准的63例KOA患者根据治疗方法的不同按随机数字表法分为ESWT组(32例)和对照组(31例)。2组均给予常规膝关节肌力训练,每日3组训练,每组10次,连续训练4周;ESWT组辅以体外冲击波疗法,压力2.5 bar,频率8.0 Hz,频次2000,每周1次,共4次;对照组患者除冲击波压力设置为0.2 bar,其余治疗步骤及治疗参数与ESWT组保持一致,共治疗4周。分别于治疗前、第5周及第12周,测评和比较2组患者的视觉模拟评分法(VAS)、西安大略和麦克马斯特大学骨关节炎(WOMAC)指数、奎森指数评分及膝关节软骨磁共振检查T2值,并记录患者可能出现的不良反应。 结果 ESWT组在第12周的VAS分值[(2.3±1.1)分],WOMAC指数[(11.3±6.8)分]和奎森指数[(3.9±2.7)分]分别较组内治疗前[(5.3±0.8)、(31.6±7.2)和(10.6±2.4)分]有明显改善(P<0.05),亦显著优于对照组在第12周时的各个评分[(4.3±1.1)、(24.5±10.1)和(8.7±3.5)分],组间差异有统计学意义(P<0.05)。ESWT组在第12周的T2值[(49.2±5.6)ms]与组内治疗前[(49.1±5.5)ms]比较,差异有统计学意义(P<0.05),但与对照组第12周的T2值[(49.1±5.8)ms]比较,差异无统计学意义(P<0.05)。研究过程中2组均未出现严重不良反应,2组出现不良反应的频次没有明显差异(P>0.05)且均在第12周时前消失。 结论 ESWT可明显改善KOA患者的下肢功能,且其对膝关节软骨的影响在安全的范围内。 相似文献
996.
铅中毒是一种铅暴露引起的直接损害神经系统并累及多种器官的疾病。由于铅在日常生活中应用广泛,铅中毒已经成为一种常见疾病。本研究就铅中毒及其对神经、造血、骨骼、生殖系统及肾脏损伤做综述,并描述应用于驱铅药物研究的细胞和动物模型以及阐述常用驱铅药物的利弊,重点介绍了通过阻断肝肠循环治疗铅中毒的研究。 相似文献
997.
目的比较4种微创方式处理复杂性输尿管上段结石的疗效,探讨治疗复杂性输尿管上段结石的合理选择。方法回顾性分析武汉大学人民医院2008年2月—2011年1月403例复杂性输尿管上段结石患者的临床资料,依据体外冲击波碎石术(ESWL)、经尿道输尿管镜碎石术(URL)、微创经皮肾镜取石术(MPCNL)及后腹腔镜输尿管切开取石术(RLU)进行分组,比较患者临床资料及各组间的手术成功率、结石清除率、并发症发生率、住院时间及治疗费用。结果 403例患者中,ESWL治疗78例,URL 136例,MPCNL 103例,RLU 86例;一次治疗成功率ESWL组为41.0%,URL组为71.3%,MPCNL组为87.4%,RLU组为97.7%;术后1个月结石清除率ESWL组为69.2%,URL组为85.3%,MPCNL组为96.1%,RLU组为100.0%;住院时间ESWL组为(4.5±1.9)d,URL组为(6.5±2.1)d,MPCNL组为(9.6±1.9)d,RLU组为(9.1±2.2)d;治疗费用ESWL组为(3 947±721)元,URL组为(7 682±937)元,MPCNL组为(12 613±1 342)元,RLU组为(13 284±1 830)元;严重并发症发生率ESWL组为零,URL组为1.5%,MPCNL组为1.0%,RLU组为零。结论 4种方法均可用于治疗复杂性输尿管上段结石,ESWL和URL治疗时间短,损伤小,MPCNL和RLU治疗时间长,结石清除率及治疗费用均较高,应根据患者的临床情况和实际要求制定相应的治疗方案。 相似文献
998.
Ali Abdul Jabbar Wayne J. Franklin Leo Simpson Andrew B. Civitello Reynolds M. Delgado III O.H. Frazier 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(1):40-43
We report the successful implantation of a HeartMate II left ventricular assist device after a failed Fontan procedure in a patient with dextro-transposition of the great arteries. The patient had developed significant intrapulmonary arteriovenous shunting. Despite the theoretical risk of worsening intrapulmonary shunting due to the decrease in systemic vascular resistance after device implantation, our patient did well. He was discharged from the hospital in stable condition and had better oxygen saturation than before the device was implanted. To our knowledge, ours is the 2nd report of the use of a ventricular assist device after the failure of a Fontan procedure, and the first report concerning the effect of ventricular assist device implantation on intrapulmonary shunting. 相似文献
999.
Mark Hammond Neil T. Lewis 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(13)
Tidally locked exoplanets likely host global atmospheric circulations with a superrotating equatorial jet, planetary-scale stationary waves, and thermally driven overturning circulation. In this work, we show that each of these features can be separated from the total circulation by using a Helmholtz decomposition, which splits the circulation into rotational (divergence-free) and divergent (vorticity-free) components. This technique is applied to the simulated circulation of a terrestrial planet and a gaseous hot Jupiter. For both planets, the rotational component comprises the equatorial jet and stationary waves, and the divergent component contains the overturning circulation. Separating out each component allows us to evaluate their spatial structure and relative contribution to the total flow. In contrast with previous work, we show that divergent velocities are not negligible when compared with rotational velocities and that divergent, overturning circulation takes the form of a single, roughly isotropic cell that ascends on the day side and descends on the night side. These conclusions are drawn for both the terrestrial case and the hot Jupiter. To illustrate the utility of the Helmholtz decomposition for studying atmospheric processes, we compute the contribution of each of the circulation components to heat transport from day side to night side. Surprisingly, we find that the divergent circulation dominates day–night heat transport in the terrestrial case and accounts for around half of the heat transport for the hot Jupiter. The relative contributions of the rotational and divergent components to day–night heat transport are likely sensitive to multiple planetary parameters and atmospheric processes and merit further study.Exoplanets, which are planets orbiting stars other than the Sun, have revealed a variety of novel forms of atmospheric circulation. The most notable of these is the circulation of tidally locked planets, which are close enough to their host star that tidal stresses between planet and star cause the planet’s orbital and rotational periods to synchronize (1, 2). These planets always present the same side to their star, yielding a permanent day side and night side.Understanding the global circulation of tidally locked planets is vital to interpreting observations of their atmospheres and studying their atmospheric stability and habitability. The circulation transports heat, chemical species, and clouds around the planet. This affects the observable “phase curve,” which is the light emitted or reflected by the planet as it rotates (3–5). Accurate retrievals of chemical composition and cloud structure depend on understanding the temperature structure of the atmosphere, which is determined by the circulation (6–9). Vertical motion in the atmosphere affects the transport and distribution of chemical species and clouds (10, 11), which will also have observable effects. In addition, the circulation may be crucial to supporting a habitable atmosphere on a terrestrial (rocky) planet, with sufficient heat transport needed to prevent volatile species from condensing on the cold night side and leading to atmospheric collapse (12–15).Previous work has shown that the circulation on tidally locked planets is driven by the strong heating/cooling gradient between their day sides and night sides (16–19). The day–night forcing generates overturning circulation, which features air rising on the day side and sinking on the night side (16). This vertical motion then leads to the generation of stationary waves (20, 21), which in turn can accelerate a prograde (superrotating) equatorial jet (21–24). However, the relative contribution of each of these components to the total circulation is poorly understood, as no study has shown how they can be isolated from one another.In this study we address this issue by showing how the overturning circulation, stationary waves, and superrotating jet can be separated out from the total circulation using a Helmholtz decomposition, which uniquely divides the total circulation into divergent (“vorticity-free”) and rotational (“divergence-free”) components (25):[1][2]Above, is the velocity potential function, and is a streamfunction. and are obtained from[3][4]where is the divergence and is the vorticity. We apply the Helmholtz decomposition to the horizontal velocity fields output from two well-studied general circulation model (GCM) simulations of tidally locked atmospheres, one representing a terrestrial planet (26) and the other a giant gaseous planet (a “hot Jupiter”) (27). Details of the numerical procedure used to invert Eqs. 3 and 4 are provided in Materials and Methods. The Helmholtz decomposition has been used extensively to study the Earth’s atmospheric circulation (25). We apply it for the first time to the atmospheric circulation of tidally locked planets.Fig. 1 shows the global circulation of the terrestrial planet and hot Jupiter simulations that we analyze in this study. The terrestrial simulation was run using the GCM Exo-FMS (24, 26), using parameters appropriate for typical terrestrial tidally locked planets, such as those in the Trappist-1 system (29). The hot Jupiter simulation was run using the GCM THOR (27, 30), configured with parameters appropriate for the planet HD 189733b (31). In both simulations, the substellar point is located at longitude, latitude. Model details and parameters are described in Materials and Methods for both cases. The data for the THOR simulation were provided to us by the developers of THOR.Open in a separate windowFig. 1.The global circulation of the idealized tidally locked planets simulated in Exo-FMS and THOR. (Left column) Terrestrial simulation, showing the height and velocity fields at 0.4 bar and the zonal-mean zonal velocity. (Right column) Hot Jupiter simulation, showing the temperature and velocity fields at 0.02 bar and the zonal-mean zonal velocity. Both simulations have the eastward equatorial jet and eastward hot-spot shift typical of tidally locked planets. For both simulations, the substellar point is located at (). We show the height field for the terrestrial case and the temperature field for the gaseous case for consistency with the original publications where their overall circulation was analyzed (26, 27). In both atmospheres, the height and temperature fields have the same qualitative structure as the thickness of a hydrostatic layer between two pressure levels is proportional to its temperature (22). This relationship is expressed by the hypsometric equation (28).Fig. 1, Left column shows the circulation of the terrestrial planet simulation. Fig. 1, Top Left shows the height and velocity field at , and Fig. 1, Bottom Left shows the zonal-mean zonal velocity. These fields show the key features of its circulation: a “hot spot” shifted eastward of the substellar point, stationary planetary-scale waves, and an eastward equatorial jet produced by these waves (22–24). Fig. 1, Right column shows the hot Jupiter. Temperature and velocity fields at are shown in Fig. 1, Top Right, and the zonal-mean zonal velocity is shown in Fig. 1, Bottom Right. This atmosphere has the same key features as the terrestrial case, despite its much higher temperature, larger size, and faster rotation rate. In this study we decompose the velocity fields of our two simulations into two physically distinct circulations and show how they relate to these key features. 相似文献
1000.
目的 评价脑干听觉诱发电位(BAEP)和血清神经元特异性烯醇化酶(s-NSE)在小儿先心病(CHD)心脏手术前后检测的意义。方法 1.测定体外循环开放式不停跳手术的CHD患儿20例手术前后BAEP的变化;2.测定心脏不停跳、停跳手术患儿各20例术前24h、术后2h、7d的s-NSE水平。结果 1.CHD患儿与对照组比较和手术前或后紫绀型先心病(CCHD)和非紫绀型先心病(NCCHD)比较,CCHD组Ⅲ-Ⅳ、Ⅰ-Ⅴ波和I-V波峰间潜伏期(IPL)显著延长(P<0.05)。2.手术组术后2h血s-NSE水平显著增高,不停跳组和停跳组平均值与术前比较差异非常显著(P<0.001);术后7d s-NSE水平上述两组与术前比较差异显著(P<0.05)。3.术后2h s-NSE水平停跳组明显高于不停跳组(P<0.001),且术后7d s-NSE水平两组比较差异显著(P<0.05)。结论 1.CCHD可伴随脑功能损害;2.s-NSE的变化可提示体外循环手术过程中的脑功能受损;3.就脑保护而言,心不停跳术式优于停跳术式。 相似文献