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51.
1993年11月至1996年5月应用改进的经尿道非接触式激光治疗前列腺增生120例,并对病人进行术前术后的症状评分,尿动力学,残余尿检查,随访病人1-24个月,结果显示病人无论是症状评分,还是尿流率,残余尿等各项指标均有明显的改善,此种手术具有简单,安全,副作用小,术后恢复快,治疗效果好等优点。 相似文献
52.
A Critical Period of Ventricular Fibrillation More Susceptible to Defibrillation: Real-Time Waveform Analysis Using a Single ECG Lead 总被引:1,自引:0,他引:1
PENG-WIE E. HSIA SYLVIA FRERK CYNTHIA A. ALLEN ROBERT M. WISE NERI M. COHEN RALPH J. DAMIANO Jr . 《Pacing and clinical electrophysiology : PACE》1996,19(4):418-430
Previous studies have suggested that variations in the underlying ventricular fibrillation (VF) waveform may be one of the factors responsible for the probabilistic nature of defibrillation. The heart appeared to be more susceptible to defibrillation at higher absolute VF voltages (AVFV). This study investigated in an open-chest canine model (n = 8), a newly developed system that analyzed the VF waveform in real-time, instantaneously determined the time to shock, and immediately delivered a fixed low energy DC shock. A two parameter tracking technique using a running long-term and short-term AVFV average was devised to automatically identify a high voltage peak area of the VF waveform, which has been hypothesized to represent a critical period susceptible to defibrillation. Using a DC shock estimated at the 50% success level, the performance using this technique in 58 defibrillation trials was compared to the performance of the conventional method of shocking at a fixed time (random shock method) in 62 trials. Patch size, electrode location, and discharge voltage were kept constant while VF duration, transmyocardial resistance (TMR), energy delivered, and AVFV at the point of shock were measured. Shock energy and current, TMR, and VF duration were similar with both shock methods. A significantly higher AVFV was observed for trials performed with the peak shock method (0.66 ± 0.02 mV) as compared to trials performed with the random shock method (0.25 ± 0.09 mV) (P < 0.003). Using lead II as the only sensing lead, the success rate was increased in 6 of 8 dogs (75%) with the new method. One animal showed identical performance, and one animal a worse performance. The overall increase in success rate was 24% using a single ECG lead (range 0%-100%; P < 0.04). Our data document that using this algorithm a period of high VF voltage can be detected in realtime. The improved success in the majority of animals supports the hypothesis that a critical period susceptible to defibrillation exists during VF. However, the high AVFV detected using a single ECG lead did not translate to an improved success rate in all animals. This suggests that other factors in addition to the VF voltage measured on a single lead of the ECG are important in characterizing this critical period. 相似文献
53.
F. Sartucci G. Orlandi U. Bonuccelli D. Borghetti L. Murri C. Orsini L. Domenici V. Porciatti 《Neurological sciences》2006,26(6):395-401
Abstract Idiopathic Parkinson’s disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms
(PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are
not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green
(R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients
(mean age: 62±7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1±8.3
years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G,
B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not
significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and
luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for
B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early
IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing
MSA from IPD. 相似文献
54.
计算机自动定量诊断脑萎缩的初步研究 总被引:2,自引:0,他引:2
目的研究正常人群脑容积随年龄及性别的变化规律,提出计算机定量诊断脑萎缩的客观标准。方法利用最新提出的脑容积计算机自动定量算法,测量了脑萎缩组487例(男,310例,女,177例)和正常组1901例(男,993例,女,908例)的颅腔容积、脑容积和脑实质分数(BPF),并通过多项式曲线拟合技术,研究正常人BPF随年龄变化的函数关系。结果正常组颅腔容积为(1271322±128699)mm3,脑容积为(1211725±122077)mm3,BPF为(95.3471±2.3453)%;脑萎缩组颅腔容积为(1276900±125180)mm3,脑容积为(1203400±117760)mm3,BPF为(91.8115±2.3035)%。两组之间的颅腔容积和脑容积差异无统计学意义(P>0.05),而BPF差异具有统计学意义(P<0.001);BPF定量与年龄之间的二次多项式函数关系P(x)=-0.0008x2+0.0193x+96.9999能够较为准确表达正常人BPF随年龄变化的函数关系,其95%可信区间下限为y=-0.0008x2+0.0184x+95.1090。结论BPF与年龄之间函数关系的95%可信区间下限,可作为计算机自动定量诊断脑萎缩的客观标准。 相似文献
55.
56.
The experiment investigated the effects in healthy volunteers of a single dose of temazepam (30 mg, oral) on effortful and automatic processing, by measuring memory for information and its context. Effortful processing was impaired, as shown by significant impairments in free recall of an 18-item list, but automatic processing was spared, as evidenced by no impairments in recall of the frequency of presentation, the colour, size or form of the items. In a second task, temazepam significantly impaired both recognition and recency memory of 30 items, although these scores were not correlated. Temazepam caused significant sedation, measured by an objective test and by subjective ratings, but this did not correlate with the memory impairments. The pattern of results is discussed with reference to the hypothesis that the memory impairments resulting from benzodiazepines are due to a reduction in information processing resources and thus affect effortful processing more than automatic processing. 相似文献
57.
Nicole C. Naus Gregorius P. M. Luyten Theo Stijnen Paul T. V. M. De Jong 《Documenta ophthalmologica. Advances in ophthalmology》1995,90(1):53-59
In this study we wanted to investigate the post-operative astigmatism and visual acuity after phacoemulsification and conventional extracapsular cataract surgery. Patients operated between April and June 1993 (n=150) were retrospectively analyzed. The patients were examined prior to surgery and at day 1, at day 10, and in week 6 post-operatively. The difference between the post-operative log mean visual acuity in the Phaco group and in the CECCE group was significant after 1 and 10 days, however it was not significant (p=0.191) after 6 weeks. The mean astigmatism was significantly less in the Phaco group than in the CECCE group during the whole post-operative check-up period. This study suggests that Phaco results in a lower post-operative astigmatism and an earlier visual rehabilitation compared to the CECCE technique.Abbreviations Phaco
Phacoemulsification
- CECCE
Conventional extracapsular cataract extraction 相似文献
58.
59.
60.
M. Doyle B. L. W. Chapman G. Blackwell E. G. Walsh G. M. Pohost 《Magnetic resonance in medicine》1994,31(5):546-550
We introduce an image processing method which reduces white noise and random artifacts in sets of high resolution, time resolved images. At each pixel, the processing consists of: (1) the isolation of a time intensity curve (TIC), (2) Fourier transformation of each TIC, (3) application of a threshold to remove low intensity coefficients, (4) inverse transformation to generate noise reduced TICS which are recombined to form images with improved signal-to-noise ratio (SNR). Noise filtering by Fourier thresholding is demonstrated on a set of cardiac images, resulting in a reduction of the noise energy by approximately 90%. 相似文献