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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Krueger K Landwehr P Bendel M Nolte M Stuetzer H Bongartz R Zaehringer M Winnekendonk G Gossmann A Mueller RP Lackner K 《Radiology》2002,224(2):519-528
PURPOSE: To report an interim analysis of whether centered endovascular irradiation with the iridium 192 ((192)Ir) source immediately after percutaneous transluminal angioplasty (PTA) of de novo femoropopliteal stenoses lowers the restenosis rate. MATERIALS AND METHODS: Thirty patients undergoing PTA to treat femoropopliteal stenoses were randomized for prophylaxis against restenosis with centered endovascular irradiation with a (192)Ir source (a dose of 14 Gy 2 mm deep to the vessel wall, irradiation group) or no irradiation (control group). Angiographic follow-up was available for 22 patients at 6 months (irradiation group, n = 10) and 12 patients at 12 months (irradiation group, n = 6). Duplex sonography, treadmill testing, and interviews were performed the day before and the day after PTA and after 1, 3, 6, 9, and 12 months. Results of angiography, duplex sonography, treadmill testing, and interviews were evaluated with a t test and multivariate analysis of variance (clinical characteristics, chi(2) test). RESULTS: Baseline characteristics were comparable in the two groups. Interim analysis of the 6-month follow-up data revealed a trend toward a significantly lower restenosis rate in the irradiation group. The change in the degree of stenosis compared with that after PTA was -14.7% +/- 20.8 (mean +/- SD) in the irradiation group versus 37.7% +/- 27.3 in the control group (P =.001) and became even more marked at 12 months (-9.5% +/- 34.5 vs 45.5% +/- 40.7 [P =.03], respectively). The follow-up results of treadmill testing and interviews showed a nonsignificant benefit for the irradiation group. One thromboembolic complication occurred during irradiation. No side effects were observed during follow-up. CONCLUSION: Endovascular irradiation with a centered (192)Ir source immediately after PTA of de novo femoropopliteal stenoses reduces the restenosis rate. 相似文献
982.
Markus P. Henkel 《MedR Medizinrecht》2002,20(11):573-577
Ohne Zusammenfassung
RID="*"
ID="*"Zugleich Besprechung der Entscheidung des BGH v. 13.6.2002 – III ZR 186/01 –, MedR 2002, S.582 (in diesem Heft); dieses
wird im folgenden nach dem Urteilsumdruck zitiert.
Rechtsanwalt Markus P. Henkel, Gottfried-Keller-Stra?e 20, D-81245 München 相似文献
983.
Non-occlusive mesenteric ischemia (NOMI) compromises all forms of mesenteric ischemia with patent mesenteric arteries. It generally affects patients over 50 years of age suffering from myocardial infarction, congestive heart failure, aortic insufficiency, renal or hepatic disease and patients following cardiac surgery. Non-occlusive disease accounts for 20-30% of all cases of acute mesenteric ischemia with a mortality rate of the order of 50%. Acute abdominal pain may be the only early presenting symptom of mesenteric ischemia. Non-invasive imaging modalities, such as CT, MRI, and ultrasound, are able to evaluate the aorta and the origins of splanchnic arteries. Despite the technical evolution of those methods, selective angiography of mesenteric arteries is still the gold standard in diagnosing peripheral splanchnic vessel disease. In early non-occlusive mesenteric ischemia, as opposed to occlusive disease, there is no surgical therapy. It is known that mesenteric vasospasm persists even after correction of the precipitating event. Vasospasm frequently responds to direct intra-arterial vasodilator therapy, which is the only treatment that has been shown to be effective. 相似文献
984.
Zaehringer M Wedekind C Gossmann A Krueger K Trenschel G Landwehr P 《European radiology》2002,12(Z3):S18-S24
Two cases of aneurysmal re-rupture during intracranial angiography are presented. This event is accompanied by disastrous consequences with regard to the clinical condition of the patient, as is evident from the cases presented as well as from the literature. Acute alterations of intraluminal pressure as well as a time interval of less than 6 h seems to increase the risk of re-bleeding during angiography. The introduction of and the growing experience with CT and MR angiography may in the near future provide sufficient diagnostic information for surgical planning and thus help to overcome the risk of aneurysmal re-rupture during intra-arterial angiography. 相似文献
985.
Zorger N Manke C Lenhart M Finkenzeller T Djavidani B Feuerbach S Link J 《Journal of vascular and interventional radiology : JVIR》2002,13(4):355-359
PURPOSE: To evaluate the effect of different balloon inflation times on angiographic results in peripheral angioplasty. MATERIALS AND METHODS: Seventy-four infrainguinal arteriosclerotic lesions were randomized prospectively to undergo balloon dilation for 30 seconds (group I) or 180 seconds (group II). Each group consisted of 37 patients. Postinterventional angiograms were evaluated by two blinded readers. Dissections were graded as follows: 1 = no dissection; 2 = minor flap; 3 = extensive dissection membrane, not flow limiting; or 4 = flow-limiting flap. The rate of major-grade dissections (grades 3 and 4), residual stenosis (>30%), and further interventions were compared with the two-tailed chi(2) test. RESULTS: In group I, major dissections were noted in 16 patients (43%) compared with five patients (14%) in group II (P =.009). Residual stenoses were found in 12 patients (32%) in group I compared with five patients (14%) in group II (P =.096). The rate of additional interventions was significantly higher in group I than in group II (20 of 37 vs nine of 37; P =.017). CONCLUSION: A prolonged inflation time of 180 seconds improves the immediate angioplasty result of infrainguinal lesions compared to a short dilation strategy. Significantly fewer major dissections and a modest reduction of residual stenoses are observed. The requirement of costly and time-consuming further interventions is significantly reduced. 相似文献
986.
Huber ME Oelhafen ME Kozerke S Weber OM Boesiger P 《Journal of magnetic resonance imaging : JMRI》2002,15(2):210-214
PURPOSE: To acquire the center of k-space while extending three-dimensional free-breathing navigator-gated coronary magnetic resonance (MR) angiography by an initial single breath-hold. MATERIALS and METHODS: This approach was successfully applied in eight healthy adult subjects. Resulting images were compared with conventionally acquired free-breathing navigator-gated MR angiograms. RESULTS: The acquisition of k-space center during the single breath-hold resulted in a 26% increase (P < 0.05) of signal-to-noise ratio. Visible length of the right coronary artery, as well as contrast-to-noise ratio between the blood and the myocardial muscle, were identical. CONCLUSION: The breath-hold extension was shown to be a valuable technique that may be combined with first-pass contrast-enhanced MR imaging. 相似文献
987.
988.
Schmidt M Fischer E Dietlein M Michel O Weber K Moka D Stennert E Schicha H 《European journal of nuclear medicine and molecular imaging》2002,29(12):1571-1580
Paragangliomas or glomus tumours of the head and neck region are rare somatostatin receptor-expressing neuroendocrine tumours. Precise preoperative diagnosis is of special importance in order to adequately weigh the potential benefit of the operation against the inherent risks of the procedure. In this study, the clinical value of somatostatin receptor imaging was assessed in 19 patients who underwent somatostatin receptor scintigraphy because of known or suspected paraganglioma of the head and neck region. The results were compared with the results of computed tomography and/or magnetic resonance imaging, histology and clinical follow-up. [(111)In-DTPA- D-Phe(1)]-octreotide scintigraphy was performed 4-6 and 24 h after i.v. injection of 140-220 MBq (111)In-octreotide. Whole-body and planar images as well as single-photon emission tomography images were acquired and lesions were graded according to qualitative tracer uptake. Somatostatin receptor imaging was positive in nine patients, identifying paragangliomas for the first time in three patients and recurrent disease in six patients. In one patient, a second, previously unknown paraganglioma site was identified. Negative results were obtained in ten patients. These patients included one suffering from chronic hyperplastic otitis externa, one with granuloma tissue and an organised haematoma, one with an acoustic neuroma, one with an asymmetric internal carotid artery, two with ectasia of the bulbus venae jugularis and one with a jugular vein thrombosis. In two patients with a strong family history of paraganglioma, individual involvement could be excluded. In only one patient did somatostatin receptor imaging and magnetic resonance imaging yield false negative results in respect of recurrent paraganglioma tissue. It is concluded that somatostatin receptor scintigraphy provides important information in patients with suspected paragangliomas of the head and neck region and has a strong impact on further therapeutic management. 相似文献
989.
Rittmeister ME Noble PC Bocell JR Alexander JW Conditt MA Kohl HW 《Acta orthopaedica Scandinavica》2002,73(1):65-71
We tested in vitro 15 Poly-L-lactic acid and 14 titanium interference screws in male human cadaver tibia-hamstring constructs. Elongation of the graft, displacement of the screw in the tibial tunnel, and slippage at the graft/screw interface were measured as outcomes with an infrared optical system. All constructs failed by slippage of the graft past the interference screw. On average, graft slippage accounted for 92% of total construct laxity at 5mm total construct elongation, whereas permanent stretching of the midsubstance of the graft accounted for only 8%. Movement of the interference screw in the tibial canal was minimal, averaging 0.01 (0-0.5) mm at construct failure. Inadequacy of isolated tibial interference screw fixation of soft tissue grafts may be overcome if early failure at the graft/screw interface is prevented. 相似文献
990.
Glypican-3 expression is markedly decreased in human gastric cancer but not in esophageal cancer 总被引:2,自引:0,他引:2
Zhu Z Friess H Kleeff J Wang L Wirtz M Zimmermann A Korc M Büchler MW 《American journal of surgery》2002,184(1):78-83
BACKGROUND: Deregulation of the expression of glypican-3, a heparan sulfate proteoglycan, has been demonstrated in several human cancers. METHODS: In the present study, glypican-3 mRNA expression was analyzed by Northern blotting and in situ hybridization in 20 normal and 41 cancerous esophageal specimens as well as in 15 normal and 32 cancerous gastric tissues. RESULTS: Glypican-3 mRNA was expressed in both normal and esophageal cancer tissues without a significant difference between normal and cancerous tissues, and without a correlation with histological type, tumor stage, tumor grade, or patient survival. Moderate to strong glypican-3 mRNA signals were found in the cytoplasm of squamous epithelial cells of the normal esophagus. In both squamous and adenocarcinomas of the esophagus glypican-3 mRNA signals were also moderately to strongly present in the cytoplasm of the cancer cells. In gastric tissues, glypican-3 mRNA was present in 53% of normal gastric tissue samples, but was below the detection level in all examined gastric cancer samples. Glypican-3 mRNA signals were moderately to strongly present in the cytoplasm of gastric mucosal epithelial cells, but were only very faintly present in some cancer cells. CONCLUSIONS: Glypican-3 may be involved in the growth control of normal esophageal and gastric epithelial cells. Furthermore, our results suggest that glypican-3 may play a tumor suppressor role in gastric but not in esophageal cancer. 相似文献