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排序方式: 共有10000条查询结果,搜索用时 406 毫秒
31.
应用食管调搏,检测64例旁道参与的房室折返性心速患者Ⅰ、Ⅱ、Ⅴ1和食管导联的室房时距、P'v,Pet时距。发现左侧AP者RP'1较RP'V1短(P<0.01),而右侧AP时较RP'v1长(P<0.01)。 相似文献
32.
MICHAL J. KANTOCH ROXANE McKAY MICHAEL J. TYRRELL 《Pacing and clinical electrophysiology : PACE》1993,16(9):1887-1891
An 11-year-old girl who underwent Mustard's operation for complete transposition of the great arteries in infancy, developed Mobitz type II second-degree AV block 81/2 years later. A transvenous, active fixation left ventricular lead was inserted and connected to a rate responsive pacemaker. Two years later the lead dislodged due to the child's growth. A new active fixation electrode was positioned in the left ventricle below the pulmonary valve, leaving an electrode loop in the ventricle. Such an approach may prevent lead dislodgement due to growth after intraatrial repair for transposition of the great arteries, but regular radiological or echocardiographic follow-up of lead position is recommended in these patients. 相似文献
33.
组合式外固定器最佳拆除 时间及有关问题探讨 总被引:4,自引:0,他引:4
作者1992年6月-1994年12月,用组合式外固定器治疗胫腓骨骨折24例,治疗过程中应用B超直方图检测骨愈合,为固定器高速及拆除提供量化指标。固定后6周,B超直方图值达到健侧50%-60%,拆除外固定更换夹板或行走石膏,为骨愈合创造较好力学环境,骨折在10-14周愈合,比通常认为需要3-5月更短。 相似文献
34.
Abstract The aim was to measure the effect of gastric electrical stimulation on the frequency of canine antral pacesetter potentials (PPs), the strength of antral contractions, and the rate of gastric emptying while fasting, after feeding and with pentagastrin stimulation. Four conscious dogs with a stimulating electrode placed 10 cm proximal to the pylorus and recording electrodes and strain gauges placed 7, 5 and 3 cm proximal to the pylorus underwent myoelectric and strain gauge recordings while fasting, after feeding (250 ml 5% dextrose labelled with polyethylene glycol), and during pentagastrin infusion (0.5 μg kg?1 min?1) on four separate days. On each day, electrical stimulation was done using one of four stimulation frequencies (0, 6, 30 and 1200 stimuli per minute ***[s.p.m.]). Stimulation at 6 and 30 s.p.m. increased the fasting and fed PP frequency, whereas 1200 s.p.m. stimulation did not. Feeding decreased the maximum driven frequency, and pentagastrin increased it. Neither the motility index nor the gastric emptying rate were consistently changed by stimulation at any frequency. In conclusion, canine proximal antral stimulation at 6 and 30 s.p.m. sped PP frequency during fasting and after feeding, but stimulation over a wide range of frequencies had little effect on gastric contractions and emptying. 相似文献
35.
Yasuhiro Yamaoka Takatomo Mine Hiroshi Tanaka Yoichiro Ishida Tosihiko Taguchi 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1346-1349
An avulsion fracture of the tibial tubercle is a common injury in traffic accident. If the fracture is closed, then a comparatively
good prognosis can be expected through reinforcement of the bone via osteosynthesis and the use of artificial ligaments. In
this case, an open wound was observed in the tibial tubercle, and the wound was so polluted that the healing process was significantly
delayed. It was therefore difficult to provide simultaneous surgical treatment and so three operations were required to perform
the reconstruction of the extensor mechanism. The reconstruction of extensor mechanism and the frame fixation between the
patella and tibia was performed. Six months after the injury, the patient was able to walk without aid, had a range of movement
from 5°to 130°, and did not show any indications of ADL disorder. Using this method of frame fixation between the patella
and tibia proved to be an effective technique for the reconstruction of the open knee extension mechanism injury. 相似文献
36.
37.
后天性外耳道狭窄的手术治疗 总被引:1,自引:0,他引:1
目的探讨后天性外耳道狭窄的手术治疗方法及效果。方法对26例(27耳)外耳道狭窄行外耳道成形术或厢乳突根治鼓室成型术,取大腿内侧自体游离中厚皮片植皮,碘仿纱条压迫并扩张耳道。结果26例病人27耳随访6个月至8年,24耳外耳道宽敞,无再狭窄;3耳出现轻度狭窄,发生率11.1%(3/27),效果满意。结论对后天性外耳道狭窄的治疗可根据狭窄的原因、部位及程度等不同情况采用外耳道成形、游离中厚皮片移植或同时进行乳突根治鼓室成型术等手术治疗,术后局部换药,即能取得较好效果。 相似文献
38.
目的探讨经体外反搏治疗的冠心病患者血清对血管内皮细胞基因表达的调控效应。方法分别取接受体外反搏治疗的冠心病患者1、24和36h时间点的血清,用于培养人脐静脉血管内皮细胞。用cDNA基因芯片检测3个治疗时点反搏前、后血管内皮细胞基因表达谱。结果反搏前后比较,有10个基因(核转录因子、真核转录启动因子-4、平滑肌的肌球蛋白重链、α2-肌动蛋白、微管蛋白β肽链、组织相容蛋白G、黑色素黏附分子、神经介素B受体、蛋白激酶4K2、血小板凝血酶敏感蛋白-1)的表达在3个治疗时点上出现显著改变。在1h点均为上调,在24h、36h时点均为下调。结论体外反搏治疗冠心病患者血清对血管内皮细胞的炎症反应、细胞凋亡相关基因表达有调效应,并随体外反搏治疗时间的增加早抑制其表达的趋势。 相似文献
39.
Willem G de Voogt Ben F M Vonk Bert A Albers Florian Hintringer 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2004,6(6):561-569
Automatic capture detection systems are currently available in several cardiac pacing devices. All current systems use low-polarization electrodes and no beat to beat detection system is available for all types of electrodes. In addition the success ratio for currently available systems is not always 100%. Failure to detect capture reliably is often related to the behaviour of the electrode-tissue interface under different circumstances. Pacemaker electrodes can be considered electrochemical cells with complicated characteristics depending on time, temperature and electrical charge. This electrochemical cell is disturbed when a charge is transferred across the electrode-tissue interface during pacing. Several measures can be taken in order to minimise this disturbance or pace polarization artefact (PPA) including the use of high active surface area electrodes and application of tri-phasic pacing pulses. Another factor influencing detection of evoked potentials is the input circuit of the pacemaker affecting the PPA and the evoked response. Positive PPAs can be falsely interpreted as evoked potentials due to the undershoot of the second order filters applied in modern cardiac pacemakers. This paper explains the behaviour of the interface between the electrode and the cardiac tissue in combination with the pacemaker output circuits and input amplifiers under different circumstances. 相似文献
40.
目的探讨面神经颅外段的动脉来源及分布. 方法 15例新鲜尸体头颈部标本经双侧颈总动脉插管,加压注入红色乳胶或过氯乙烯填充剂,观察面神经颅外段的血供来源及分布. 结果面神经营养动脉来源于耳后动脉的茎乳动脉、颞浅动脉面神经支、面横动脉、颈外动脉上面神经支、颈外动脉下面神经支、面动脉后面神经支和面动脉前面神经支,其外径分别为(0.8±0.2) mm、(0.9±0.4) mm、(1.9±0.3) mm、(1.0±0.2) mm、(1.1±0.4) mm、(1.0±0.2) mm和(1.1±0.6) mm.各营养动脉除营养面神经外还发出分支相互吻合,构成了丰富的面神经血管网. 结论了解面神经颅外段动脉血供来源及分布,为避免腮腺咬肌区手术损伤面神经营养血管提供了解剖学基础. 相似文献