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21.
Pieter M. Groenendijk August A. B. Lycklama Nijeholt Theo J. Ouwerkerk Ubi van den Hombergh 《Neuromodulation》2007,10(4):363-368
Objective. We studied long‐term clinical efficacy of sacral neuromodulation (SNM) therapy in patients with refractory urgency incontinence (UI), urgency/frequency (UF) and voiding difficulty (VD), together with urodynamic data at baseline and six months postimplant. Materials and Methods. Twenty‐two patients were implanted with a neurostimulator after a positive response to a percutaneous nerve evaluation test defined as a greater than 50% improvement in symptoms. Results. At five‐year follow‐up, the number of incontinent episodes and pad usage per day decreased significantly in 10 out of 15 UI patients. Two of five UF patients were successfully treated with SNM; the number of daily voids for all UF patients decreased from 25 to 19 and average voided volume increased from 98 to 212 mL. One of the two VD patients was able to void to completion. Mean first sensation of filling at the six‐month urodynamic investigation for the UI and UF patients increased from 78 to 241 mL and 141 to 232 mL, respectively, and the maximum bladder capacity increased from 292 to 352 mL and 223 to 318 mL, respectively. Five of 22 patients underwent device explant and one patient still has an inactive stimulator implanted. Conclusion. SNM is an effective treatment modality that offers sustained clinical benefit in the majority of patients with refractory UI, UF, and VD that do not respond to other, more conservative therapies. 相似文献
22.
目的:探讨彩色多普勒多参数分析对乳腺良、恶性肿块鉴别诊断的价值。材料和方法:应用高频彩色多普勒对96例104个乳腺实质肿块进行扫查,观察肿块的彩色多普勒血流信号及多普勒血流频谱形态,与手术病理结果对照分析。结果:64.4%的良性肿块可检出血流信号,血流信号多为Ⅰ~Ⅱ级,良性肿块中血流频谱以低阻力搏动型及静脉型多见,91.1%的乳腺恶性肿块可检出血流信号,血流信号多为Ⅱ~Ⅲ级,恶性肿块的血流频谱形态较多样化,即同时有多种血流频谱,且以高阻力搏动型和湍流型为多见。结论:高频彩色多普勒超声多参数综合分析有助于临床对乳腺肿块的诊断及鉴别诊断。 相似文献
23.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
24.
目的 分析组织激肽释放酶基因 5’端启动子区域多态性在四川地区汉族人群中的分布。方法 应同PCR技术结合等位基因特异寡核苷酸片段分析的方法 (ASO)对 13 2例四川地区健康汉族人的组织激肽释放酶基因用十种探针进行检测 ,分析等位基因频率的分布。结果 组织激肽释放酶基因的A、B、C、D、E、H、K、P的频率分别为 2 2 .7%、9.8%、9.8%、3 .0 %、9.1%、2 3 .1%、16.3 %、6.1%。结论 在我国四川地区的健康汉族人群中 ,该位点确实存在多态性。 相似文献
25.
26.
Image processing is a critical part of obtaining high-quality digital radiographs. Fortunately, the user of these systems does not need to understand image processing in detail, because the manufacturers provide good starting values. Because radiologists may have different preferences in image appearance, it is helpful to know that many aspects of image appearance can be changed by image processing, and a new preferred setting can be loaded into the computer and saved so that it can become the new standard processing method.Image processing allows one to change the overall optical density of an image and to change its contrast. Spatial frequency processing allows an image to be sharpened, improving its appearance. It also allows noise to be blurred so that it is less visible. Care is necessary to avoid the introduction of artifacts or the hiding of mediastinal tubes. 相似文献
27.
Michael Bach Graham E. Holder 《Documenta ophthalmologica. Advances in ophthalmology》1996,92(3):193-202
The pattern electroretinogram was recorded to checkerboard stimuli with a wide range of check sizes and two stimulus field
sizes. Check sizes ranged from 0.25° to 7° (field size, 16°×14°) and 0.25° to 15° (field size, 32°×27°) in 14 and seven subjects,
respectively. Reversal rate was 4.5/s. For minimal intrusion of blink artifacts the interrupted stimulation technique was
employed. The P50 and N95 components of the pattern electroretinogram were evaluated separately. With both stimulus field
sizes amplitude of P50 and N95 was maximal between 0.75° and 1°. With smaller check sizes the amplitude dropped monotonically.
With larger check sizes field size played a role: with the 16°×14° field, P50 gradually dropped to 89% from 1° to 7°, which
was paralleled by N95 only up to 7°, where N95 dropped to 81% (p<0.05). With the 32°×27° field, there was no significant difference in size dependency between P50 and N95 for large checks,
both components staying constant from 1° to 15° We conclude that there is only minor large-check attenuation of the pattern
electroretinogram, especially with a large field. The apparent field-size dependency may explain previous discrepancies in
the literature. 相似文献
28.
正常闪光视网膜电图的频域分析 总被引:3,自引:0,他引:3
应用快速傅里叶转换技术对正常视网膜电图进行频域分析,发现其a、b波的优势频及能量集中在5-75Hz;与OPS波的分离点为77HZ,从而提出单纯记录a、b波及OPS波各自的较理想的通频带。 相似文献
29.
Peter Schnider MD Joachim Maly PhD Josef Grünberger PhD Susanne Aull MD Karl Zeiler MD Peter Wessely MD 《Headache》1995,35(5):269-272
A considerable proportion of headache patients fulfill the criteria of "drug abuse" (definition according to the International Headache Society [IHS] criteria). These patients exhibit markedly reduced vigilance and continuous performance, as shown by the results of critical flicker frequency (CFF) analysis.
The present study deals with the question whether this impairment of vigilance and continuous performance is reversible. Forty-eight headache patients with drug abuse were investigated three times by means of CFF analysis: immediately before (A), immediately after (B), and 3 weeks after having finished (C) inpatient drug withdrawal.
Immediately after withdrawal, a significant decrease of headache intensity was observed. The CFF values, however, remained unchanged at a depressed level, probably due to withdrawal medication and the initial sedative side effects of thymoleptic agents (given as prophylaxis).
Three weeks after withdrawal, however, the CFF values were significantly improved, and were now within a range not far from the normal values known from a healthy general population. Thus, even after many years of drug abuse, headache patients have a good chance to improve their vigilance and continuous performance and to reach normal or close to normal levels. 相似文献
The present study deals with the question whether this impairment of vigilance and continuous performance is reversible. Forty-eight headache patients with drug abuse were investigated three times by means of CFF analysis: immediately before (A), immediately after (B), and 3 weeks after having finished (C) inpatient drug withdrawal.
Immediately after withdrawal, a significant decrease of headache intensity was observed. The CFF values, however, remained unchanged at a depressed level, probably due to withdrawal medication and the initial sedative side effects of thymoleptic agents (given as prophylaxis).
Three weeks after withdrawal, however, the CFF values were significantly improved, and were now within a range not far from the normal values known from a healthy general population. Thus, even after many years of drug abuse, headache patients have a good chance to improve their vigilance and continuous performance and to reach normal or close to normal levels. 相似文献
30.
高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化 总被引:1,自引:0,他引:1
目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断. 相似文献