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排序方式: 共有498条查询结果,搜索用时 23 毫秒
1.
Nevo N. Goldstein A. L. Staierman M. Eran N. Carmeli I. Rayman S. mnouskin Y. 《Hernia》2022,26(6):1491-1499
Hernia - The minimally invasive surgical repair of combined inguinal and ventral hernias often requires shifting from one approach or plane to another. The traditional enhanced-view totally... 相似文献
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Shahar Cohen Sarit Soffer-Hirschberg Shirly Partouche Benny Hovav Michael Gurevich Vadym Mezhybovsky Vladimir Tennak Sigal Eisner Eviatar Nesher Eytan Mor Eli Atar 《Artificial organs》2020,44(10):1073-1080
Perfusion decellularization has been proposed as a promising method for generating nonimmunogenic organs from allogeneic or xenogeneic donors. Several imaging modalities have been used to assess vascular integrity in bioengineered organs with no consistency in the methodology used. Here, we studied the use of fluoroscopic angiography performed under controlled flow conditions for vascular integrity assessment in bioengineered kidneys. Porcine kidneys underwent ex vivo angiography before and after perfusion decellularization. Arterial and venous patencies were defined as visualization of contrast medium (CM) in distal capillaries and renal vein, respectively. Changes in vascular permeability were visualized and quantified. No differences in patency were detected in decellularized kidneys compared with native kidneys. However, focal parenchymal opacities and significant delay in CM clearance were detected in decellularized kidneys, indicating increased permeability. Biopsy-induced leakage was visualized in both groups, with digital subtraction angiography revealing minimal CM leakage earlier than nonsubtracted fluoroscopy. In summary, quantitative assessment of vascular permeability should be coupled with patency when studying the effect of perfusion decellularization on kidney vasculature. Flow-controlled angiography should be considered as the method of choice for vascular assessment in bioengineered kidneys. Adopting this methodology for organs premodified ex vivo under normothermic machine perfusion settings is also suggested. 相似文献
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Quantitation of basal dyssynchrony and acute resynchronization from left or biventricular pacing by novel echo-contrast variability imaging 总被引:4,自引:0,他引:4
Kawaguchi M Murabayashi T Fetics BJ Nelson GS Samejima H Nevo E Kass DA 《Journal of the American College of Cardiology》2002,39(12):2052-2058
OBJECTIVES: This study sought to test a novel echocardiographic method based on contrast variability imaging (CVI), to quantify cardiac dyssynchrony and magnitude of resynchronization achieved by left ventricular (LV) and biventricular (BiV) pacing therapy. BACKGROUND: Left ventricular or BiV pacing is a promising new therapy for patients with heart failure and intraventricular conduction delay. However, precise quantitation of the extent of resynchronization achieved remains scant. METHODS: Ten patients treated with BiV or LV pacing therapy were studied. Echo-contrast was infused slowly, and gated images were acquired before and during contrast appearance. The temporally normalized variance derived from 30 to 50 sequential beats was determined at each pixel to yield the CVI image-displaying improved wall delineation. Systolic regional fractional area of radial sectors was calculated with active and temporarily suspended (AAI) pacing. All analyses were performed blinded to both patient and treatment. RESULTS: Pacing increased septal inward motion from -20.4 +/- 9.6% to -30.5 +/- 14.0%, whereas lateral wall motion occurred earlier with no net magnitude change. Both spatial and temporal dyssynchrony in the LV declined nearly 40% with LV or BiV pacing (p < or = 0.001), and this correlated with increasing ejection fraction (31% to 39%; p < 0.02; p < 0.004 for correlation with dyssynchrony). CONCLUSIONS: The new imaging and regional dyssynchrony analysis methods provide quantitative assessment of resynchronization analogous to that previously obtained only by tagged magnetic resonance imaging. This could provide a useful noninvasive method for both identifying candidates and following long-term therapy. 相似文献
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Taizo Murabayashi Barry Fetics David Kass Erez Nevo Boris Gramatikov Ronald D Berger 《Journal of electrocardiology》2002,35(1):19-25
Beat-to-beat QT interval variability (QTV) quantifies lability in ventricular repolarization. We hypothesized that myocardial ischemia destabilizes ventricular repolarization and increases QTV. We analyzed 2-hour 2-lead digitized electrocardiogram records of 68 patients in the European ST-T Database. All patients had ischemic episodes during the 2-hour record, annotated by the developers of the database. We determined the normalized QTV (QTVnorm), QT variability index (QTVI), and normalized heart rate variability (HRVnorm) for each 5-minute epoch by automated analysis. QTVnorm was greater during ischemic episodes than during nonischemic episodes (1.41 +/- 0.77 vs. 0.88 +/- 0.23, P <.0001). There was no significant difference in HRVnorm between ischemic and nonischemic episodes (1.22 +/- 0.63 vs. 0.94 +/- 0.18, not significant). The QTVI was higher during ischemic episodes than during nonischemic episodes (0.14 +/- 0.31 vs. -0.051 +/- 0.12, P <.0001). Acute ischemia is associated with labile ventricular repolarization, which manifests as enhanced beat-to-beat QT interval variability. The association between ischemic repolarization liability and arrhythmic risk deserves further study. 相似文献
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Domestication quantitative trait loci in Triticum dicoccoides,the progenitor of wheat 总被引:7,自引:0,他引:7 下载免费PDF全文
Peng J Ronin Y Fahima T Röder MS Li Y Nevo E Korol A 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(5):2489-2494
Wild emmer wheat, Triticum dicoccoides, is the progenitor of modern tetraploid and hexaploid cultivated wheats. Our objective was to map domestication-related quantitative trait loci (QTL) in T. dicoccoides. The studied traits include brittle rachis, heading date, plant height, grain size, yield, and yield components. Our mapping population was derived from a cross between T. dicoccoides and Triticum durum. Approximately 70 domestication QTL effects were detected, nonrandomly distributed among and along chromosomes. Seven domestication syndrome factors were proposed, each affecting 5-11 traits. We showed: (i) clustering and strong effects of some QTLs; (ii) remarkable genomic association of strong domestication-related QTLs with gene-rich regions; and (iii) unexpected predominance of QTL effects in the A genome. The A genome of wheat may have played a more important role than the B genome during domestication evolution. The cryptic beneficial alleles at specific QTLs derived from T. dicoccoides may contribute to wheat and cereal improvement. 相似文献
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Improved regional left ventricular function after successful satellite cell grafting in rabbits with myocardial infarction 总被引:3,自引:0,他引:3
Blatt A Robinson D Cotter G Efrati S Simantov Y Bar I Kaluski E Krakover R Sidenko S Evron Z Lipa L Posternak N Nevo Z Vered Z 《European journal of heart failure》2003,5(6):751-757
OBJECTIVE: To evaluate whether satellite cells injected into infarct areas in rabbits remain viable during 6 weeks follow-up and can improve cardiac function as assessed by echocardiography. METHODS: Myocardial infarction was induced in 16 New Zealand white rabbits, by ligation of the marginalis sinistra artery. Tissue from gluteus muscle biopsies was dissected into small pieces and cultured. Within 2-3 weeks the cells were expanded by 2-3 orders of magnitude and were fluorescent labeled. Single cell pellets for resuspension at >10(6)/1 ml were directly injected into the infarct areas in 8 rabbits. In 8 additional rabbits, 1 ml saline was injected (control). Regional left ventricular function was assessed weekly by 2-D echocardiography until animals were sacrificed. Analysis was performed blind and independently by two experienced echocardiographers, based on the American Society of Echocardiography scheme. RESULTS AND DISCUSSION: Six treated and five control rabbits completed the study. One week after the artery occlusion, left ventricular function scoring did not differ between groups, mean 8.7+/-1.6 vs 8.3+/-1.9 (P=0.74). At 6 weeks post-injection, echocardiographic score was significantly better in the treated group, mean 2.6+/-0.9 vs 6.9+/-2.1 (P=0.002). The treated group showed significant gradual segmental improvement between the first week up to week 6. After sacrifice, macro and microscopic transmural areas showed typical changes of myocardial infarction. Histochemical staining identified viable grafted cells in high density 6 weeks post-transplantation in all grafted hearts. CONCLUSION: Autologous satellite cells (skeletal myofiber), can be successfully grafted into rabbit hearts following myocardial infarction and may induce improved regional left ventricular function. 相似文献