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91.
Vanishing fluid collections in interlobar fissures, associated with congestive cardiac failure, are uncommon but well-recognized. Previous studies have highlighted the occurrence of solitary vanishing ‘tumours’, but in the study reported here 7 out of 12 consecutive patients presented with more than one interlobar fluid collection simulating pulmonary tumours. In most cases a lateral radiograph confirmed the correct diagnosis and in all cases follow-up radiographs demonstrated resolution of all pleural fluid collections. In one case ultrasound was helpful. Making the correct diagnosis is very important inorder to prevent inappropriate investigations and treatment such as biopsy or surgery. It is suggested that unusual pleural fluid collections may be more common in communities where pleural disease following stab wounds or tuberculosis are more prevalent. 相似文献
92.
David P. Faxon David Holmes Geoffrey Hartzler Spencer B. King Gerald Dorros 《Catheterization and cardiovascular interventions》1992,25(1):1-3
At present, the majority of cardiac catheterization laboratories acquire and store hemo-dynamic data in analog form. To examine the possibility of performing complex analysis of digital data during the catheterization procedure, we examined whether virtual realtime digital (fast Fourier) analysis improves the accuracy of clinical data. We compared digital filtering of fluid manometry during right heart catheterization with 10-Hz and 250-Hz analog filters. Using the simultaneously acquired micromanometry as the “gold standard,” we found that analog filtering is associated with a greater error and time delay than digital filtering. This study demonstrates that digital hemodynamic data analysis performed during cardiac catheterization can improve the quality of data obtained during right heart catheterization, with the results available within seconds. More extensive use of computers in the cardiac catheterization laboratory may be useful for both clinical and research purposes. © 1992 Wiley-Liss, Inc. 相似文献
93.
Changes in cardiac output and in superior mesenteric arterial flow were followed with Doppler ultrasound techniques in five young, healthy persons for 2 h after ingestion of medium-sized (4 MJ), fluid meals containing either carbohydrate, protein, fat or water only. Measurements were carried out before meals and at regular post-meal intervals, during which mean arterial blood pressure was also followed. All energy-containing meals caused marked and gradually developing post-prandial increases in cardiac output as well as in superior mesenteric arterial flow. The maximum flow levels were reached in the course of 30–60 min and maintained until the observations ended after 2 h. The intake of water caused no such flow increases. There were considerable interpersonal variations in the size and in the speed of development of the flow increases after the three types of energy-containing meals. The flow-increasing effects of the three meal types were not significantly different, even if the most marked increases (median values about 1 1 min-1 for both cardiac output and superior mesenteric arterial flow) occurred after carbohydrate meals. The marked effects on circulation of the three food components were also revealed in the calculated, integrated amounts of ‘extra’ cardiac output and superior mesenteric arterial flow observed in the course of the 2 h following the meal. Values of more than 100 1 for such ‘extra’ flows were seen after carbohydrate meals. The marked ingestion-released increase in blood flow to the splanchnic organs is apparently partly met by an increase in cardiac output, and partly by some redistribution of flow, which benefits the digestive system. 相似文献
94.
Vivian L. Clark T. Barry Levine 《Catheterization and cardiovascular interventions》1992,25(2):132-134
A 60 year male, orthotopic heart transplant recipient developed a fatal left ventricular outflow obstruction secondary to thrombus at 38 months post transplant. Although he had episodes of mild to moderate rejection at 2 and 16 months post transplant, subsequent biopsies were negative and annual cardiac catheterizations showed mild left ventricular hypokinesis and normal coronary arteries. This case represents a catastrophic complication of transplant rejection and illustrates the problems with identifying rejection using current diagnostic methods. 相似文献
95.
96.
NESTOR G. SEPULVEDA Ph.D. JOHN P. WIKSWO Jr. Ph.D. 《Journal of cardiovascular electrophysiology》1994,5(3):258-267
Bipolar Stimulation of the Cardiac Bidomain. Introduction: One of the fundamental electrophysiologic problems that has not yet been completely elucidated is the response of cardiac tissue to externally applied electric currents. A limited number of theoretical and experimental techniques has been used to study the electric behavior of cardiac tissue in the presence of stimulating currents, and to demonstrate that the anisotropy in the passive electrical properties of the tissue plays an important role in the genesis and propagation of the activation wave-front and the resulting potential distributions.
Methods and Results: In this work we have applied the finite element method to study the electric and magnetic fields produced by cardiac tissue in response to bipolar current injection, using a linear bidomain model to represent the tissue. We found that the transmembrane potential distribution close to the stimulus electrode has a rather complex geometrical pattern, with adjacent hyperpolarized and depolarized regions.
Conclusion: This behavior is consistent with previous theoretical and experimental results and may have implications in the study of electrical stimulation of cardiac tissue that are not apparent using other models. 相似文献
Methods and Results: In this work we have applied the finite element method to study the electric and magnetic fields produced by cardiac tissue in response to bipolar current injection, using a linear bidomain model to represent the tissue. We found that the transmembrane potential distribution close to the stimulus electrode has a rather complex geometrical pattern, with adjacent hyperpolarized and depolarized regions.
Conclusion: This behavior is consistent with previous theoretical and experimental results and may have implications in the study of electrical stimulation of cardiac tissue that are not apparent using other models. 相似文献
97.
雷公藤氯内酯醇对大鼠异位心脏移植免疫抑制作用的实验研究 总被引:2,自引:0,他引:2
本研究应用纯系大鼠(Lou→F344)心脏移植模型,比较分析了CsA和不同剂量T4治疗组的移植心脏存活时间、病理损害计分以及移植受体大鼠脾单个核细胞IL-2生成活性和血清sIL-2R水平,证实T4可明显延长移植心脏存活时间和减少移植排异反应程度。此研究结果表明T4具有较强的抗移植排异作用。 相似文献
98.
99.
Atrial fibrillation (AF) is the most common cardiac arrhythmia among the elderly. Its incidence increases dramatically with increasing age and decreasing left ventrieular function, peaking in subjects with overt congestive heart failure, Because of the unsatisfactory efficacy and possible serious side effects of clinically available anti-AF drugs for AF patients with sick sinus syndrome, pacing techniques have recently been applied in the treatment of AF. The cardiac pacemaker Vitatron 相似文献
100.
杨洪涛 《中国中西医结合肾病杂志》2007,8(9):517-521,I0001
目的:观察活血软坚方对大鼠膜性肾小球肾炎(MN)肾小管间质损害的影响,并探讨活血软坚中药对MN伴发小管间质损伤的作用机制。方法:用阳离子化牛血清白蛋白复制大鼠MN模型,将实验动物随机分为正常组、模型组、雷公藤组、治疗组,观察24h尿蛋白、血浆白蛋白、胆固醇、三酰甘油、血肌酐、尿素氮等生化指标,并对肾组织进行光镜、电镜、免疫荧光观察;采用RT—PCR的方法检测ColⅠmRNA和ColⅢmRNA的表达。结果:本方能明显降低蛋白尿及血清胆固醇、三酰甘油、血肌酐、尿素氮,升高血清白蛋白,减少免疫复合物沉积,改善肾小球及肾小管的病理损伤。结论:活血软坚方能减轻尿蛋白对肾小管的损伤,减少细胞外基质在肾间质的积聚,减轻肾脏病理损伤,从而达到保护肾功能的作用。 相似文献