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1.
Claude Clément MD Roberto Ruiz MD Bogdan Costa-Foru MD Hubert Nicaise MD 《Annals of vascular surgery》1990,4(3):305-308
Extrinsic compression of the renal artery due to a fibromuscular band originating from the diaphragm was encountered in a 26-year-old patient who had systemic hypertension associated with stenosis and kinking of one of her renal arteries. After surgical decompression, the renal artery assumed a normal expansion with disappearance of hypertension. Six other cases of extrinsic compression of the renal artery have been found in the literature. Surgical treatment is mandatory in all cases because the mechanism that causes the lesion makes percutaneous transluminal angioplasty illusory. 相似文献
2.
CLOTBUST: Design of a Randomized Trial of Ultrasound-Enhanced Thrombolysis for Acute Ischemic Stroke 总被引:4,自引:0,他引:4
Andrei V. Alexandrov MD Anne W. Wojner PhD James C. Grotta MD 《Journal of neuroimaging》2004,14(2):108-112
BACKGROUND: Intravenous tissue plasminogen activator (TPA) therapy can be monitored with 2 MHz transcranial Doppler (TCD). This article describes the design of CLOTBUST (combined lysis of thrombus in brain ischemia using transcranial ultrasound and systemic TPA), the first prospective international multicenter randomized clinical trial of noninvasive externally applied ultrasound to enhance systemic thrombolysis in human stroke. SUBJECTS: Patients with acute ischemic stroke eligible for intravenous TPA therapy within 3 hours of symptom onset who have detectable middle cerebral artery occlusion on a prebolus TCD are included in this trial. All patients receive standard 0.9 mg/kg TPA therapy. Patients are randomized (1:1) to either 2 hours of continuous monitoring with TCD or placebo monitoring. FDA-approved portable diagnostic TCD equipment and standard headframes (Marc series, Spencer Technologies, Seattle, WA) are used. Output of TCD units is set at 100% power achievable at depths of insonation that display the worst TIBI flow grade signals. METHODS AND END-POINTS: Acute MCA occlusion on prebolus TCD is defined as thrombolysis in brain ischemia (TIBI) flow grades 0-3. Treating physicians are blinded to randomization assignment, and certified scorers measure stroke severity using the National Institute of Health Stroke Scale (NIHSS). Safety of continuous TCD monitoring is determined by rates of symptomatic (NIHSS score increase by 4+ points) intracerebral hemorrhage within 72 hours after initial symptom onset. Potential enhancement of TPA therapy will be determined using combined primary end-point of early complete recanalization on TCD (TIBI flow grades 4-5), dramatic recovery (NIHSS < or = 3 points), or decline in the NIHSS > or = 10 points repeatedly measured every 30 minutes within 2 hours after TPA bolus. Other end-points include recovery at 24 hours and 3 months, modified Rankin scores (mRS) are obtained at 90 days, and favorable outcome is determined as NIHSS or mRS scores 0-1. CONCLUSIONS: The aim of phase II CLOTBUST trial is to determine the rates of early complete recanalization and dramatic/early clinical recovery in TPA + TCD and TPA groups. The sample size is set at 126 patients since a medium effect size (.50) is anticipated for TPA + TCD group vs TPA alone to achieve combined primary end-point. 相似文献
3.
Sofya N Pchelina Andrei F Yakimovskii Olga N Ivanova Anton K Emelianov Andrei H Zakharchuk Alexander L Schwarzman 《Movement disorders》2006,21(12):2234-2236
Among mutations associated with autosomal dominant and sporadic Parkinson's disease (PD) the G2019S substitution in the leucine-rich repeat kinase 2 (LRRK2) gene is the most frequently identified. To estimate its frequency in Russia, we analyzed 208 patients with PD from the Northwestern region of Russia. Of these, 51 patients were probands from families with PD compatible with autosomal dominant inheritance. The control group represented 161 subjects without neurological disorders settled in the same region. The frequency of the G2019S mutation was greater in familial PD (2 [3.9%] of 51) than in sporadic PD (1 [0.6%] of 157). In addition, this mutation was found in the proband's father, who also had PD, in 1 PD family, and in 1 carrier without signs of PD at age 40 in another PD family. All carriers were heterozygous for the G2019S mutation and reported the Ashkenazi Jewish origin. The mutation was not found in the control group. 相似文献
4.
Residual Flow Signals Predict Complete Recanalization in Stroke Patients Treated With TPA 总被引:4,自引:0,他引:4
Lise A. Labiche MD Marc Malkoff MD Andrei V. Alexandrov MD 《Journal of neuroimaging》2003,13(1):28-33
BACKGROUND: Residual blood flow around thrombus prior to treatment predicts success of coronary thrombolysis. The authors aimed to correlate the presence of residual flow signals in the middle cerebral artery (MCA) with completeness of recanalization after intravenous tissue plasminogen activator (TPA). METHODS: The authors studied consecutive patients treated with intravenous TPA therapy who had a proximal MCA occlusion on pretreatment transcranial Doppler (TCD). Patients were continuously monitored for 2 hours after TPA bolus. Absent residual flow signals correspond to the thrombolysis in brain ischemia (TIBI) 0 grade, and the presence of residual flow signals was determined as TIBI 1-3 flow grades. Complete recanalization was defined as flow improvement to TIBI grades 4-5. RESULTS: Seventy-five patients with a proximal MCA occlusion had median pre-bolus NIHSS 16 (85% with > or = 10 points). TPA bolus was given at 141 +/- 56 minutes (median 120 minutes). Complete recanalization was observed in 25 (33%), partial in 23 (31%), and no early recanalization was seen in 27 (36%) patients within 2 hours after TPA bolus. Only 19% with absent residual flow signals (TIBI grade 0, n = 26) on pretreatment TCD had complete early recanalization. If pretreatment TCD showed the presence of any residual flow (TIBI 1-3, n = 49), 41% had complete recanalization within 2 hours of TPA bolus (P = .03). CONCLUSIONS: Patients with detectable residual flow signals before IV TPA bolus are twice as likely to have early complete recanalization. Those with no detectable residual flow signals have less than 20% chance for complete early recanalization with intravenous TPA and may be candidates for intra-arterial therapies. 相似文献
5.
A A Timofeev V A Znamenski? T G Vo?tsekhovskaia A I Gorban' N V Bogdan N A Kravets 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1990,(1):37-38
The use for local treatment in 45 patients with abscesses and phlegmons of lysozyme immobilized in polymethylsiloxane contributed to acceleration in wound cleaning of necrotic masses, active granulation and epithelization, reduction in duration of patients' treatment by 3-5 days. 相似文献
6.
Paulo R. Dellani Martin Glaser Paulo R. Wille Goran Vucurevic Axel Stadie Thomas Bauermann Andrei Tropine Axel Perneczky Aldo von Wangenheim Peter Stoeter 《Journal of digital imaging》2007,20(1):88-97
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation. 相似文献
7.
Chromophobe renal cell carcinoma with sarcomatoid transformation 总被引:2,自引:0,他引:2
We present a rare case of a chromophobe renal cell carcinoma that progressed to a high-grade spindle cell sarcoma. The tumor affected a 50-year-old man who had presented with right upper quadrant discomfort and hematuria and subsequently underwent a right radical nephrectomy. Microscopically, the tumor was composed of two distinct components, a chromophobe renal cell carcinoma and a sarcomatoid component. The sarcomatoid component had exhibited aggressive behavior by spreading to a regional lymph node. This case report shows that chromophobe carcinoma can develop a sarcomatoid transformation with a high propensity for invasive growth and metastasis. 相似文献
8.
Bogdan Karakašević 《Medical microbiology and immunology》1955,142(1):27-37
Ohne Zusammenfassung 相似文献
9.
10.
Vasili V. Korshak Anna P. Suprun Grigorii L. Slonimskii Andrei A. Askadskii Tatyana M. Birshtein Irina I. Vointseva Balakhanum B. Mustafayeva Oleg G. Nikolskii 《Macromolecular chemistry and physics.》1986,187(9):2153-2178
The influence of formation conditions on structure and properties of reaction products from two different macromolecules (paired polymers) such as polystyrene and poly(1,1,2-trichlorobutadiene) or polystyrene and poly(vinyl chloride) is investigated. Mechanical properties, molecular mobility, heat resistance, thermostability, and fire resistance are shown to be regulated over a wide range by changing the molecular weight of the initial polymers, their ratio in the reaction mixture, etc. The interaction of different macromolecules in solution to form paired polymers is analyzed theoretically and experimentally. An analysis of structure and properties of the resulting products by refractometry, viscometry, sedimentation velocity, statistical analysis, and others shows that paired polymers are systems of the “coil-in-coil” type held together by chemical bonds in the zones of mutual penetration. 相似文献