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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
LI-FERN HSU PIERRE JAÏS MÉLÈZE HOCINI PRASHANTHAN SANDERS MARTIN ROTTER YOSHIHIDE TAKAHASHI CHRISTOPHE SCAVÉE FREDERIC SACHER JACQUES CLÉMENTY MICHEL HAÏSSAGUERRE 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S94-S98
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation. 相似文献
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23.
目的探讨利用球囊导管加压注射泛影葡胺行子宫输卵管造影的应用价值。方法对219例不孕症用76%泛影葡胺采用球囊导管加压注射法作子宫输卵管造影检查,并在透视下实时点片。结果普通注射时双侧输卵管显示185例(84.47%),单侧显示24例;加压注射后203例(92.69%)双侧输卵管显示,单侧显示14例,成功率100%。子宫畸形见于9例,输卵管异常131例,造影剂弥散与吸收异常104例。结论利用球囊导管加压注射水溶性造影剂,可以明显提高子宫输卵管造影质量及输卵管再通效果,有重要的临床价值。 相似文献
24.
目的:分析阵发性室上性心动过速患者行射频消融术(RFCA)后复发的原因,探讨降低RFCA复发的方法。方法:128例阵发性室上性心动过速患者,行RFCA治疗,术后每3-6个月随访1次,随访4-70个月。结果:128例患者中,复发10例,总复发率7.81%,其中房室结折返性心运过速复发率为7.89%,左侧房室旁路介导心运过速复发率5.56%,右侧旁路介导心动过速复发率16.67%。行射频消融术前70例患者中复发率11.43%,后58例复发率3.45%。结论:精确的靶点标测、熟练的操作技巧以及消融方式的正确运用是降低RFCA复发率的关键。 相似文献
25.
26.
双J管临床应用及美蓝在置管术中的作用 总被引:1,自引:0,他引:1
目的探讨双J管(双J输尿管支架管)在泌尿系疾病治疗中的应用效果以及美蓝在置放术中的作用。方法对215例患者采用放置双J管作内支架和内引流治疗,近期48例术中以美蓝协助定位。结果术后留置尿管5~7d,无切口感染、尿瘘等并发症。术后1~3个月拔除双J管,随访3~6个月,肾功能、肾积水明显好转,吻合口通畅。以美蓝协助定位者无双J管上移致拔管困难。结论双J管具有内支架和内引流作用,操作简单,引流效果好,并发症少,缩短住院时间。以美蓝协助定位,值得推广应用。 相似文献
27.
To evaluate the long-term effects of entacapone on both mean daily 'on' time and health-related quality of life (QoL) in patients with Parkinson's disease (PD) experiencing 'end-of-dose' motor fluctuations and the benefits of an early therapeutic intervention. A prospective, multicenter, observational, 12-month study was performed with an initial 3-month intervention phase, consisting of a phone call to half of the patients from randomly selected investigators to assess if dose adjustment was necessary. Effectiveness was determined by home diaries ('on' time), subscales II and III of the Unified Parkinson's Disease Rating Scale (UPDRS), and the Parkinson's Disease Questionnaire (PDQ-8). After 3 months of treatment, 4.0% of the intervention group patients discontinued the study, versus 18.4% in the control group ( P < 0.01). The improvement in 'on' time was significantly increased since the 3-month visit (21%, P < 0.0001) until the end of the study (23% at 12 months, P < 0.0001). Entacapone also induced significant reductions in the UPDRS scores for subscales II and III and in the PDQ-8 score. 11.2% of patients experienced at least one adverse reaction. This study confirms the effectiveness of entacapone in reducing motor fluctuations by increasing 'on' time, and in improving QoL of PD patients. An early adjustment of entacapone and levodopa doses reduces the number of treatment discontinuations during the first months of treatment. 相似文献
28.
The early maintenance of long-term potentiation (LTP) was studied in the CA1 region of hippocampal slices from 12- to 18-day-old rats in a low-magnesium solution (0.1 mM). The α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptor-mediated components of the field excitatory postsynaptic potential were estimated in parallel using early and late measurements of the composite potential. At the normal test stimulus frequency of 0.1 Hz, LTP was seen initially as a predominant increase in the AMPA component, but converted, via a substantial decay of this component and a gradual growth of the NMDA component, into nearly equal changes of the two components. Interrupting the test stimulation for 10 min, changing the test stimulus frequency to 1/60 Hz after LTP induction, or using a test stimulus frequency of 1/60 Hz during the entire experiment significantly reduced the decay of the potentiation of the AMPA component while enhancing the potentiation of the NMDA one. The ratio between the magnitudes of the two excitatory postsynaptic potential (EPSP) components showed a decaying time course that was independent of the manipulations used. Application of the NMDA antagonist D(-)-2-amino-5-phosphonopentanoic acid (50μM) after LTP induction stabilized the LTP of the AMPA component until washout was started. On the other hand, the phosphatase inhibitor okadaic acid (1 μM) resulted in decay of the potentiation of both EPSP components back to around baseline and altered the time course of the ratio between the components. Our results show that the early maintenance of LTP is controlled in an activity-dependent and NMDA-dependent manner. This process accelerates the decay of LTP of both AMPA and NMDA components in parallel, suggesting that it is similar to homosynaptic long-term depression, although it operates at the normal test stimulus frequency. The data support a scenario in which LTP ensues as a selective AMPA receptor modification and subsequently converts to another modification, possibly a presynaptic one. 相似文献
29.
A VDD pacing system with bipolar single-pass leads, were implanted in 36 consecutive patients (average age 72 ± 2years) with high degree atrioventricular block and normal sinus node function. At implant the atrial signal amplitude was 2.6 ± 0.2mV measured by a pacing system analyser (PSA), 1.8 ± 0.1mV measured peak-to-peak from the telemetered calibrated electrogram, and 1.3 ± 0.1mV measured from the sensing threshold. At one month follow-up the peak-to-peak amplitudes (mV) of the telemetered atrial electrograms were not significantly different measured continuously during resting supine with quiet breathing (1.4 ± 0.1), sitting (1.6 ± 0.2). standing (1.5 ± 0.1), arm swinging (1.4 ± 0.2), hyperventilation (1.3 ± 0.1), Vaisalva manoeuvre (1.4 ± 0.1), and treadmill exercise (1.9 ± 0.6). The telemetered atrial electrogram amplitude and the atrial sensing threshold varied between 1.2 ± 0.09mV and 1.8 ± 0.1mV, and between 0.95 ± 0.07mV and 1.3 ± 0.01mV, respectively at 0.5, 1, 3, 6 and 12 months follow-up, but the changes were statistically nonsignificant. The Event Summary showed sensing of 98% to 99% of the atrial events at the different follow-up periods. 相似文献
30.
Kohei Hara MD PhD Shigeru Kohno MD PhD Hironobu Koga MD PhD 《Journal of infection and chemotherapy》1996,1(3):166-176
Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such
as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have
many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can
easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures
can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those
with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated
patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic
efficacy.
Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various
problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However,
the importance of accurately determining the causative organism in respiratory infections should be recognized as the most
important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment
of respiratory infections in a wide variety of patients. 相似文献