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81.
Antoine Feydy MD PhD Alexandre Krainik MD Bernard Bussel MD Marc A. Maier PhD 《Journal of neuroimaging》2004,14(1):49-53
The authors report the case of a 33-year-old woman who exhibited, at the age of 17, a left-sided hemiplegia, which was followed by good motor recovery, though with a permanent deficit in fine finger movements. She had a widespread loss of neural tissue in the right hemisphere (crossed cerebrocerebellar atrophy), including (1) marked atrophy and thinning of the precentral and postcentral gyri; (2) widespread deep white matter destruction, including the corticospinal tract; and (3) crossed cerebellar atrophy. Except over the supplementary motor area (SMA), transcranial magnetic stimulation did not elicit motor evoked potentials in the affected hand. Nevertheless, during opening and closing of the affected hand, functional magnetic resonance imaging showed an activation of the lesioned primary sensorimotor cortex (SMC), as well as of the intact SMA and the parietal areas, but not of the ipsilateral motor areas. The authors speculate that recovery was achieved by a motor command generated in the SMC and the parietal cortex, passing through corticospinal axons originating in the SMA. 相似文献
82.
HIROMI KUMON HIDEO OZAWA HIROYUKI NOSE HIDEKUNI OHTA KAZU NISHIGAKI 《International journal of urology》2004,11(8):628-633
BACKGROUND: We have developed velocity-flow urodynamics using Doppler sonography based on the hypothesis that microbubbles formed in the urethra are responsible for Doppler signals. In order to confirm this hypothesis derived from Bernoulli's principle, we investigated the simultaneous detection of cavitation noise and Doppler signals in an experimental system. METHODS: An experimental circuit was built in which a stenosis was created using a glass or silicon tube with tap water used as the sample fluid. Doppler signals, pressure before and after the stenosis, flow rate, flow velocity and cavitation noise were measured. Direct detection of cavitation with a high-speed charged-coupled device (CCD) camera was conducted in the glass tube. The relationship between cross-sectional area and flow velocity in terms of the detection of Doppler signals was analyzed in the silicon tube study. RESULTS: In the glass tube study, a high-speed CCD camera clearly detected masses of microbubbles associated with cavitation. The range of flow rates creating cavitation completely corresponded with those producing Doppler signals detected by ultrasonography. A similar correlation was observed in the silicon tube study, which showed that a low flow velocity of 41.5 cm/sec through a stenosis with a cross-sectional area of 20 mm(2) created Doppler signals at a flow rate of 8.3 mL/sec. CONCLUSION: The results of the present study confirmed that microbubbles created in flowing urine are responsible for Doppler signals. Measurement of velocity-flow urodynamics has great potential to become a non-invasive and reliable alternative to conventional pressure- flow urodynamic studies. 相似文献
83.
M. Bertolotto G. Serafini L. Dogliotti N. Gandolfo N. G. Gandolfo M. Belgrano F. Prefumo 《Abdominal imaging》2004,30(1):108-112
Cancer of the penis is a rare neoplasm in developed countries but worldwide represents a significant health problem. In this
study, the ultrasonographic features of primary and secondary malignant lesions of the penis are described. Squamous cell
carcinoma usually presents as a hypoechoic lesion with heterogeneous appearance. Invasions of the corpora cavernosa and the
corpus spongiosum are appreciable. B-cell lymphoma presents as a well-vascularized mass, a plaque, or ulcers in the penile
skin. Penile metastases result from hematogenous or lymphatic spreading of distant tumors or, more frequently, as penile infiltration
by tumors from adjacent organs. Diffuse corporeal or nodular involvement can result.
1Award-winning poster at the 10th European Symposium on Urogenital Radiology; Uppsala, Sweden, September 4•7, 2003. 相似文献
84.
85.
负压对缺血肢体血流动力学影响的实验研究 总被引:2,自引:0,他引:2
目的:观察负压对肢体动脉闭塞犬患肢血流动力学的影响。方法:犬15只,随机分治疗组10只和对照组5只。两组均采用切断犬后肢股动脉分支、动脉腔内置入螺旋状金属丝的方法,制作肢体缺血模型。在模型制作后2wk,治疗组行患肢负压治疗10d,对照组不做负压治疗。两组均于模型前、模型后2wk及治疗结束后,用彩色多普勒观察患肢股动脉血流动力学指标:收缩期最大流速(Vmax)、平均流速(Vmean)、阻力指数(R1)、搏动指数(P1)的变化。结果:治疗组在治疗后患肢股动脉Vmax、Vmean显著增加(P<0.001),RI、PI显著降低(P<0.01);对照组各指标无明显变化(P>0.05)。结论:负压对缺血肢体血流动力学表现为流速增加,阻力下降。 相似文献
86.
彩色多普勒超声在精索扭转诊断和鉴别诊断中的价值 总被引:8,自引:1,他引:7
目的 :应用彩色多普勒超声鉴别精索扭转和急性睾丸炎。 方法 :回顾性分析 13例急性睾丸疼痛病人的彩色多普勒血流显像 (CDFI)表现和治疗情况。 结果 :8例显示睾丸内血流信号稀疏或消失 ,诊断为精索扭转 ,其中 1例手法复位成功 ,7例手术探查并得以证实。其余 5例显示患侧睾丸血流信号丰富 ,诊断为急性睾丸炎或睾丸附睾炎 ,经抗生素治疗后症状好转 ,超声复查显示血流减少。 结论 :CDFI在精索扭转诊断和鉴别诊断中具有重要意义 ,可作为急性睾丸疼痛病人的首选检查方法 相似文献
87.
Andrew M Speer Mark W Willis Peter Herscovitch Margaret Daube-Witherspoon Jennifer Repella Shelton Brenda E Benson Robert M Post Eric M Wassermann 《Neuropsychopharmacology》2003,54(8):818-825
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1. 相似文献
88.
自杀基因联合中医药疗法治疗肿瘤的设想 总被引:8,自引:1,他引:7
自杀基因疗法是一种具有良好应用前景的肿瘤治疗新措施。但如何有效提高疗效是目前仍须解决的关键性问题。由于免疫机制在自杀基因疗法旁杀伤效应中的重要作用,激活荷瘤机体的免疫功能,改善自杀基因抗肿瘤作用的炎症免疫微环境,是提高肿瘤自杀基因疗法疗效的主要策略。中医中药在调节机体免疫状态方面具有肯定的作用,与其他方法比较具有明显优势。因而,将自杀基因疗法与中医中药联合应用,有可能起到提高肿瘤自杀基因疗法疗效,防止肿瘤复发的作用。提出了自杀基因联合中医药疗法治疗肿瘤的新设想,为肿瘤基因治疗提供了一种新的思路和模式。 相似文献
89.
正常人肺静脉管径及其血流频谱的研究 总被引:1,自引:0,他引:1
肺静脉血流和肺静脉管径的变化与左房压力及左心室舒张功能密切相关 [1 ,4 ] 。超声心动图可以直接、动态观察肺静脉内径及血流频谱变化 ,但是目前超声尚无健康人肺静脉内径正常值。我们应用彩色超声多普勒技术对正常人及孕周 2 4周以上的妊娠妇女进行肺静脉内径及血流频谱研究 ,以探索正常人肺静脉的显示率、内径正常值、血流频谱特点。观察高动力状态及呼吸对肺静脉管径和血流频谱的影响。1 材料与方法1.1 研究对象 16 9例排除心肺疾患的健康人分组进行研究。其中成年男性组 4 4例、成年女性组 4 6例、儿童组 14例、中期妊娠组 (中妊 … 相似文献
90.
William M. Chadduck H. Mark Crabtree James B. Blankenship James Adametz 《Child's nervous system》1991,7(1):27-30
Previous studies have demonstrated a high correlation between hydrocephalus and the resistive index (RI), as determined by transcranial Doppler ultrasonography. Measurements of RI, calculated by dividing the difference between the peak systolic velocity and the enddiastolic velocity by the peak systolic velocity, were attempted in 55 pediatric patients during evaluations for ventriculoperitoneal shunt malfunctions; values were obtained in 52. Indications of shunt malfunction included both clinical and radiographic evidence of increased intracranial pressure. Eleven patients, determined to have functional shunts both by clincal criteria and subsequent outcome, had RIs of 47±5 (average±1 standard deviation). Shunt malfunctions were confirmed in 41 patients. Prior to shunt revisions, these 41 patients has RIs of 71±10%; following revision, the RIs fell to 53±12%. Nine patients had had pre-malfunction RIs of 48±11% obtained during routine follow-ups; when they subsequently had shunt malfunctions, their RIs had significantly increased. Four of the 41 patients with shunt malfunctions had essentially normal RIs (52±7%), but had fluid tracking along the shunt; in these, RIs were essentially unaffected by shunt revision. For comparison, 119 pediatric patients with clinically functional ventriculoperitoneal shunts had RIs of 50±9%. The data, statistically significant with a P value of <0.001, showed a correlation between elevated RIs and shunt malfunction; thus, transcranial Doppler ultrasonography is a practical, non-invasive technique useful in the diagnosis of ventriculoperitoneal shunt malfunction.Presented at the Annual Meeting of the Pediatric Section of the American Association of Neurological Surgeons, Washington D.C., November 1989 相似文献