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151.
The Effect of 50 Hz External Electrical Interference on Implanted Cardiac Pacemakers 总被引:2,自引:0,他引:2
GERALD C. KAYE GHAZWAN S. BUTROUS ALI ALLEN STUART J. MELDRUM JOHN G. MALE † A. JOHN CAMM 《Pacing and clinical electrophysiology : PACE》1988,11(7):999-1008
The effects of injected 50 Hz alternating current on the function of cardiac pacemakers has been observed in 18 patients with implanted unipolar VVI units. Current, in the range 0-600 microA was applied via electrodes attached to the patients' upper body and feet and fed from a specially designed current injection unit at the bedside. Most implanted pacemakers reverted to interference mode in the current range 29-250 microA. At current levels just below the reversion current all units developed irregular and inappropriate pacing. This current level was pacemaker dependent and varied in the range 27-246 microA. The total reversion current depended on the location of the injecting electrodes and on the patients' posture. The sensitivity of the units to injected interference was increased by deep inspiration. Temporary pacing catheters fitted to an additional ten patients were used to monitor the interference voltage which would be sensed by an implanted unit. This voltage was similarly dependent on patient posture and on deep respiration. Current injection has proved to be a safe, controllable and reproducible method of testing the sensitivity of implanted pacemakers to 50 Hz external interference. 相似文献
152.
我们以糖皮质激素受体(GR)的竞争性拮抗剂RU38486(简称RU486)阻断大鼠体内的GR,并通过检测肺、肾组织匀浆中荧光标记白蛋白的含量,观察了烫伤后12h大鼠肺、肾血管壁通透性的变化以及阻断GR对这种变化的影响。结果显示:烫伤后12h,大鼠肺、肾组织匀浆中荧光标记白蛋白含量明显高于对照组(肺:P<0.05;肾:P<0.001);阻断GR后再烫伤大鼠,其肺、肾组织匀浆中的荧光白蛋白含量又显著高于烫伤组(P<0.05)。提示:①烫伤后12h,大鼠肺、肾血管壁通透性明显升高。②GR减少可加重烫伤所致的血管壁通透性升高,并可逆转内源性糖皮质激素(GC)稳定血管壁通透性的作用。 相似文献
153.
HIDEAKI SENZAKI MATSUKO SUDA SEIJI NOMA HARUO KAWAGUCHI YOICHI SAKAKIHARA TOSHIO HISHI 《Pediatrics international》1994,36(4):443-447
Acute renal failure and acute heart failure are rare in Kawasaki disease. We experienced two patients with Kawasaki disease who presented acute renal failure and acute heart failure. These two patients gave us an important insight into the understanding of water balance and fluid therapy in Kawasaki disease. One patient showed acute prerenal failure due to fluid exudation from the intravascular to the extravascular space, and subsequent acute heart failure. The other patient showed acute heart failure caused by fluid infusion for the treatment of dehydration. It is suggested that acute renal failure could be caused by a fluid shift from the intravascular to the extravascular space in Kawasaki disease. It is also demonstrated that the reserve of cardiac function could be decreased in patients with Kawasaki disease due to myocarditis even with normal echocardiography and chest X-rays. 相似文献
154.
用吐温80-乙醚(TE)法、蔗糖-丙酮(SA)法、丙酮-乙醚(AE)法分别从肾综合征出血热病毒(HFRSV)感染的Vero-E6细胞培养和乳小白鼠脑组织中制备病毒血凝素(HAN),定量对比证明其制备效果,结果无明显差异。粗制HAN经高压液相色谱(EPLC)纯化,有4个洗脱峰,血凝活性物质存在于峰1。纯化HAN在SDS-PAGE中呈单一区带,分子量56.6KD,HAN相对含量79.6%。纯化HAN在蔗糖密度梯度液中有一条1.15~1.16g/cm3的沉淀,粗制HAN有3条沉淀。电镜观察纯化HAN中为大小相等的球状颗粒。粗制HAN的高密度沉淀中可见到病样颗粒。对几种常用消毒剂、氧化剂、去垢剂对HAN的灭活作用做了实验对比观察。 相似文献
155.
PHARMACOKINETICSOFCUPRIC-BIS(SALICYLALDEHYDE-2-FURANTHIOCARBOXY-HYDRAZONATE)DICHLORIDE(CSFTCH)INRABBITS¥GaoYunsheng;ZhuYuyun(... 相似文献
156.
Respiratory symptoms associated with the use of azodicarbonamide foaming agent in a plastics injection molding facility 总被引:1,自引:0,他引:1
L W Whitehead T G Robins L J Fine D J Hansen 《American journal of industrial medicine》1987,11(1):83-92
Respiratory health variables were studied cross-sectionally in 227 employees of a plastics molding facility where numerous complaints had been apparently associated with the use of azodicarbonamide foaming agent in injection molding. Pre- and postshift respiratory status measures and azodicarbonamide concentrations were also obtained for 17 employees. Cross-sectional pulmonary function differences by injection molding status were not observed. Modest decrements in pulmonary function measures were observed between start and end of shift but with no dose-effect relationship. A strong association was observed for injection molding workers for eye/nose/throat irritation, cough, and wheezing. Additionally, wheezing, chest tightness, and symptoms of chronic bronchitis were strongly associated with work in injection molding during periods in which azodicarbonamide was in use. These results suggest respiratory symptom causation by some combination of azodicarbonamide itself, reaction products of azodicarbonamide formed during injection molding, or other unidentified agents uniquely associated with the process of injection molding with azodicarbonamide foaming agent. 相似文献
157.
158.
159.
根据蓝四氮唑与泼尼松生成蓝色产物,并于525nm 波长处测定吸光度。测定条件为:反应管长度为3.8m(0.5mm id);流速为1.6ml/min;反应温度为55±0.5℃;注射样品溶液为100μl;本测定系统的测定速度可达100次/h;线性范围可达0.09mg/ml;检测限量为1.54μg/ml;测定结果的变异系数小于1%。 相似文献
160.
朱永萍 《天津医科大学学报》2003,9(1):69-71
目的:评价老年性白内障超声乳化伴人工晶体植入术心电监护的临床意义。方法:随机选择老年性白内障超声乳化伴人工晶体植入术行心电监护244例(287只眼)。结果:手术中出现血压明显升高,心肌缺血及心律失常者114例,经及时处理后恢复。结论:老年性白内障患者,术中行心电监护对提高手术安全性十分重要。 相似文献