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排序方式: 共有3453条查询结果,搜索用时 15 毫秒
41.
Urban O Vitek P Fojtik P Kliment M Janik D Chalupa J Albin A 《Hepato-gastroenterology》2008,55(82-83):351-355
BACKGROUND/AIMS: Laterally spreading tumors (LST) are flat elevated neoplastic lesions with diameters equal to or greater than 10 mm. The treatment results of 138 lesions in 131 patients are presented here as a part of a retrospective analysis. METHODOLOGY: Two gastroenterology centers participated in the study in the period from 1/2002-12/2006. During colonoscopy, each superficial lesion was classified according to the Paris endoscopic classification. Endoscopic mucosal resection (EMR) lift and cut was employed. Treatment was considered successful when both endoscopic and histo-pathological criteria of complete resection were fulfilled. RESULTS: A total of 138 LST in 131 patients were diagnosed. Average LST diameter was 25 mm. A total of 5 (3.6%) lesions in 4 patients were referred for primary surgery. One patient was treated with argon plasma coagulation only. EMR was attempted for 132/138 (95.7%) of all LST and was successful in 125 (90.6%) cases. Complications occured in 16/132 (12.1%) patients. Severe complications, defined as decession, emergency surgery, emergency endoscopy and transfusion of eryhrocyte concentrate occured in 5/132 (3.8%). One (0.7%) 69 year-old-male patient died on the third day following EMR due to complications of acute myocardial infarction. CONCLUSION: LST lesions could be efficiently treated with EMR lift and cut method with a reasonable rate of complications. 相似文献
42.
43.
Goure J Broz P Attree O Cornelis GR Attree I 《The Journal of infectious diseases》2005,192(2):218-225
Pathogenic Yersinia species and Pseudomonas aeruginosa share a similar type III secretion/translocation system. The translocation system consists of 3 secreted proteins, YopB/PopB, YopD/PopD, and LcrV/PcrV; the latter is known to be a protective antigen. In an in vitro assay, the translocation system causes the lysis of erythrocytes infected with wild-type (wt) P. aeruginosa. wt Y. enterocolitica is not hemolytic, but a multiknockout mutant deprived of all the effectors and of YopN ( Delta HOPEMN) is hemolytic. In the presence of antibodies against PcrV and Y. pestis LcrV, the hemolytic activity of P. aeruginosa was inhibited. Similarly, the hemolytic activity of Delta HOPEMN was inhibited in the presence of anti-LcrV antibodies. The assembly of the translocon, composed of PopB/D and YopB/D proteins, was disturbed in immunoprotected erythrocyte membranes, mimicking the phenotypes of V knockout mutants. Thus, protective antibodies against the V antigens of Yersinia species and P. aeruginosa act at the level of the formation of the translocon pore in membranes of infected host cells by blocking the function of LcrV/PcrV. The hemolysis assay could be adapted for high-throughput screening of anti-infectious compounds that specifically target the type III translocon. 相似文献
44.
Alan Bulava Petr Heinc Martin Hutyra Milan Kaminek Malvina Krivankova Marek Richter Jan Lukl 《Journal of interventional cardiac electrophysiology》2006,16(2):117-122
A sixty-year-old man with previous history of coronary artery disease was admitted due to progressive worsening of dyspnoea at exertion (NYHA III functional class) and no angina. Coronary angiography confirmed occlusion of the right coronary artery which was naturally bypassed by homocollaterals with TIMI 3 flow to the peripheral branches. The lesion was not technically suitable for percutaneous angioplasty. The left coronary artery was without stenosis. On echocardiography, both the left ventricle and the left atrium were dilated and hemodynamically significant mitral regurgitation was present. Surface ECG showed a left bundle branch block with repeated runs of monomorphic ventricular ectopic beats (PVC). Radiofrequency catheter ablation of the focus in the posteroseptal region of the left ventricle underneath the mitral valve was performed using electroanatomical mapping system. After the procedure, mitral regurgitation decreased and reverse remodeling of the left ventricle and the left atrium occurred with concomitant significant clinical improvement of the patient. The authors discuss several treatment strategies: mitral valve repair surgery combined with revascularization, implantation of a biventricular ICD system or elimination of the focus of monomorphic VT runs by radiofrequency catheter ablation as a possible causal approach in the treatment of PVC-induced cardiomyopathy. 相似文献
45.
Gurpreet Singh Dhillon Shohreh Honarbakhsh Antonio Di Monaco Ann Elizabeth Coling Kernerov Lenka Francesca Pizzamiglio Ross J. Hunter Rodney Horton Moussa Mansour Andrea Natale Vivek Reddy Massimo Grimaldi Petr Neuzil Claudio Tondo Richard J. Schilling 《Journal of cardiovascular electrophysiology》2020,31(6):1259-1269
46.
Arnot Vespalec Josef Novk Alena Kohoutkov Petr Vosynek Jan Podrouek David karoupka Tom Zikmund Josef Kaiser David Palouek 《Materials》2020,13(22)
3D concrete printing technology (3DCP) is a relatively new technology that was first established in the 1990s. The main weakness of the technology is the interface strength between the extruded layers, which are deposited at different time intervals. Consequently, the interface strength is assumed to vary in relation to the time of concrete casting. The proposed experimental study investigated the behavior of a hardened concrete mixture containing coarse aggregates that were up to 8 mm in size, which is rather unusual for 3DCP technology. The resulting direct tensile strength at the layer interface was investigated for various time intervals of deposition from the initial mixing of concrete components. To better understand the material behavior at the layer interface area, computed tomography (CT) scanning was conducted, where the volumetric and area analysis enabled validation of the pore size and count distribution in accordance with the layer deposition process. The analyzed CT data related the macroscopic anisotropy and the resulting crack pattern to the temporal and spatial variability that is inherent to the additive manufacturing process at construction scales while providing additional insights into the porosity formation during the extrusion of the cementitious composite. The observed results contribute to previous investigations in this field by demonstrating the causal relationships, namely, how the interface strength development is determined by time, deposition process, and pore size distribution. Moreover, in regard to the printability of the proposed coarse aggregate mixture, the specific time interval is presented and its interplay with interface roughness and porosity is discussed. 相似文献
47.
New-generation oxide dispersion-strengthened (ODS) alloys with a high volume fraction of nano-oxides of 5% are intended to become the leading creep- and oxidation-resistant alloys for applications at 1100–1300 °C. Hot consolidation of mechanically alloyed powders by intensive plastic deformation followed by heat treatment of the alloys are the key aspects for achieving top creep properties, typically ensured by a coarse-grained microstructure strengthened with homogeneously dispersed, very stable yttrium nano-oxides. The rotary swaging method proves to be favourable for hot consolidation of the new-generation ODS alloy presented. Compared to specimens consolidated by hot rolling, consolidation by hot rotary swaging predetermines the formation of coarse grains with a very high aspect ratio during subsequent secondary recrystallization. Such a grain morphology increases the creep strength of the new-generation ODS alloy considerably. 相似文献
48.
Atrial fibrillation (AF) ablation is a complex procedure that requires transseptal puncture and extensive manipulation with catheter(s) in the left atrium and pulmonary veins. Individual anatomy of these structures contributes to a challenge of AF ablation. The proximity of surrounding structures, such as esophagus, further increases risk of complications of this procedure. Increased risk of intracardiac thrombosis associated with AF is another factor that may complicate management of these patients. For all these reasons, imaging techniques play increasingly important role. Preprocedural imaging becomes important not only to rule out thrombus but also for assessment of anatomy of the PVs and left atrium, left atrial size and the extent of a substrate. Various forms of imaging help significantly during the procedure both with identification of anatomy and with catheter navigation. Many studies have shown increased efficacy, safety and decreased fluoroscopy times. After the procedure, imaging techniques such as echocardiography, CT or MR imaging are useful to diagnose potential complications. This paper briefly reviews clinical utility of different imaging tools for ablation of AF. 相似文献
49.
Endoglin (CD 105, TGF-β receptor III) is a homodimeric transmembrane glycoprotein that plays a regulatory role in TGF-β signaling. Its functional role in the context of atherosclerosis has yet to be defined and should be stated here. Therefore, we focused on the role of endoglin in atherosclerosis in both humans and experimental animals. Endoglin expression was demonstrated in atherosclerotic vessels predominantly in endothelial cells and smooth muscle cells in various types of blood vessels in mice and humans, suggesting its participation in atherogenesis. Endoglin expression was also related to the expression of eNOS in endothelium, repair of the vessel wall, plaque neoangiogenesis, production of collagen and stabilization of atherosclerotic lesions. In addition, increased levels of soluble endoglin were associated with hypercholesterolemia, atherosclerosis, acute myocardial infarction and were related to inhibition of TGF-β signaling in the vessel wall. Moreover, soluble endoglin levels were significantly lowered after a series of extracorporeal eliminations in patients with familial hypercholesterolemia. Additionally, statin treatment decreased levels of soluble endoglin and increased its expression in aorta, which was related to reduced atherosclerosis in mice. In conclusion, we propose that measurement of soluble endoglin might give information about progression of the atherosclerotic process or the efficacy of therapeutic interventions, which is the task that must be answered in clinical trials. 相似文献
50.
Krone N Reisch N Idkowiak J Dhir V Ivison HE Hughes BA Rose IT O'Neil DM Vijzelaar R Smith MJ MacDonald F Cole TR Adolphs N Barton JS Blair EM Braddock SR Collins F Cragun DL Dattani MT Day R Dougan S Feist M Gottschalk ME Gregory JW Haim M Harrison R Olney AH Hauffa BP Hindmarsh PC Hopkin RJ Jira PE Kempers M Kerstens MN Khalifa MM Köhler B Maiter D Nielsen S O'Riordan SM Roth CL Shane KP Silink M Stikkelbroeck NM Sweeney E Szarras-Czapnik M Waterson JR Williamson L Hartmann MF Taylor NF 《The Journal of clinical endocrinology and metabolism》2012,97(2):E257-E267