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11.
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
12.
Takashi Toyonaga Eisei Nishino Takashi Hirooka Chie Ueda Kazu Noda 《Digestive endoscopy》2006,18(Z1):S123-S127
To control intraoperative bleeding is an important key to successful endoscopic submucosal dissection. The distribution of submucosal vessels encountered during the procedure differ in places in the stomach and are roughly categorized into three groups: those located in the antrum, those in the lesser curvature, and those on the anteroposterior corpus wall which consists of oblique muscle layers. Therefore, knowledge of a suitable setting of diathermy and adjusted depth of dissection in the submucosal layer for each site is imperative. The combination of utilizing the distal attachment forced or swift coagulation (trimming with coagulation mode) have enable the treatment with an insulation tipped knife safer. 相似文献
13.
目的 本文采用彩色多普勒超声心动图研究了心脏起搏前、后的血液动力学变化 ,以评价不同起搏模式血液动力学效应。方法 对 32例植入人工心脏起搏器的患者 ,采用 M型、二维及多普勒超声心动图检测了心室按需起搏 (VVI)不伴室房逆传 (A组 )和伴室房逆传 (B组 )及房室顺序起搏 (AVP) (C组 )的左心结构、左室的泵血功能、左室收缩及舒张功能指标。结果 1 .心室起搏 (VP)不伴室房逆传和房室顺序起搏(AVP)组起搏后的心输出量 (CO)明显增加 (P<0 .0 5〉,而 VP伴室房逆传组则 CO增加不明显 (P>0 .0 5 )。心搏量 (SV)各组均呈下降趋势 ,VP伴室房逆传者下降更明显。但起搏后三组间比较无显著差异 (P>0 .0 5 ) ;2 .VP后左室的收缩及舒张功能均有受损 ,而 AVP后主要损害左室的舒张功能 ,对左室收缩功能影响不明显 ;3.VP伴室房逆传者 ,起搏后血液动力学效应在三组间最差。结论 无论 VP还是 AVP起搏后由于心率的增加均可使CO增加 ,但对左室的功能均有不同程度的损害 ,VP伴室房逆传者最为明显 ,AVP损害程度三组间最轻。因此 ,AVP也并非真正的生理起搏器。临床上提倡埋植更接进生理状态的起搏器 (多部位心脏起搏 ) ,以保持良好的心功能状态 相似文献
14.
Richard M. Pearson 《Clinical & experimental optometry》1990,73(6):172-177
A simple but reliable method was used to measure the axial edge lift at the total diameter over a range of back optic zone radii of several proprietary designs of rigid gas-permeable corneal lens. One of these was found to have a constant axial edge lift construction. 相似文献
15.
OLE-GUNNAR ANFINSEN ERIK KONGSGAARD ARNOLD FOERSTER HALFDAN AASS JAN P. AMLIE 《Pacing and clinical electrophysiology : PACE》1998,21(1):69-78
Interruption of atrial flutter and fibrillation by RF catheter ablation may be favored by large, elongated lesions. We administered RF current in unipolar and bipolar mode in porcine right atrium. Bipolar ablation was performed between the tip electrodes of two serially coupled catheters. With 4-mm tip electrodes in vitro, lesion length increased from a mean (SD) of 7.9 (1.2) mm at 3 mm-interelectrode distance (IED) to 13.3 (3.3) mm at 9-mm IED, but decreased at 12-mm IED due to nonconfluent lesions (P < 0.0001), With 4 mm distal electrodes and 8 mm IED, bipolar lesions were 65% longer than corresponding unipolar ablations. Switching to bipolar mode increased the lesion length more than increasing electrode tip length to 6 mm in unipolar mode. Power and temperature controlled ablation created equally sized lesions. Twelve anesthetized pigs were randomized to unipolar or two catheter bipolar temperature controlled ablation of the right atrial free wall. Bipolar ablation created confluent lesions with endocardial length × width of 13.5 (5.8) × 7.3 (3.7) mm, unipolar ablation 6.4 (2.8) × 4.6 (1.4) mm (P < 0.001 when comparing length and P = 0.013 for lesion width). The atrial lesions in both groups were transmural and extended into hilar lung lesions with maximal depth of 3.0 (1.1) and 2.6 (1.0) mm, respectively (P = 0.44). Five bipolarly and four unipolarly ablated pigs developed right diaphragmal paresis. We conclude that bipolar ablation may be preferable in situations where large, elongated lesions are favorable. The two catheter technique is feasible in porcine right atrium. Both bipolar and unipolar ablation of the porcine right atrial free wall may frequently be complicated by injury to the phrenic nerve and adjacent lung tissue. 相似文献
16.
以市场需求为导向探索"宽口径大基础后分流"医学教育模式 总被引:5,自引:0,他引:5
郭清 《中国高等医学教育》2002,(3):19-20
在分析了我国医学教育现状的基础上 ,结合浙江省社会经济发展和医学教育的实际 ,提出医学教育必须以市场需求为导向 ,积极探索“宽口径、大基础、后分流”医学教育新模式 ,并从理论的高度 ,结合本校创办卫生管理专业的初步实践经验 ,分析了这种医学教育模式的特点和优点 相似文献
17.
18.
通过对所在中医医院ISO9001族质量管理体系实施过程中历次内部审核的总结,探索既符合中医医院实际工作又满足标准要求的内部审核模式,形成科学化的内审流程。 相似文献
19.
论述了医疗保障制度改革给医院带来的机遇与挑战,认为医院应采取调整结构,转换运行机制;完善补偿机制;加大宏观调控力度,制订和实施区域卫生规划等配套措施,来适应医疗保障制度的改革。 相似文献
20.
O. N. Tatarinova T. N. Lukyanova M. A. Zaitseva K. Yu. Veremeev V. A. Karpov A. N. Chuvilin D. D. Petrunin G. E. Pozmogova 《Bulletin of experimental biology and medicine》2008,145(3):312-316
Analysis of the use of real-time PCR with fluorescent registration of results for gene diagnosis of infectious diseases showed
that the sensitivity and reliability of quantitative evaluation of DNA targets directly depended on the method of purification
of oligonucleotide probes. Chromatographic behavior of synthetic probes carrying various fluorophores and fluorescence quenchers
was analyzed. Approaches to optimization of purification methods are proposed enabling elimination of previously undetectable
admixtures. The importance of these studies is explained by the need in extending the armory of methods for the development
and production of diagnosticums for detection of infectious and hereditary diseases, identification of genetically modified
organisms, and for a wide spectrum of research in molecular biology and medicine.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 3, pp. 280–284, March, 2008 相似文献