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排序方式: 共有536条查询结果,搜索用时 15 毫秒
531.
Transition of a cancer patient from curative to palliative stage is one of the most difficult and challenging phases of cancer care both from patient and physician point of view. Most of the time the treating surgeons are expected to facilitate this transition but due to a number of reasons surgeons often fail to fulfill this crucial responsibility. This article highlights the various issues involved in the transition phase from a surgeons perspective. 相似文献
532.
Sander CJ Verfaillie Sandeep SV Golla Tessa Timmers Hayel Tuncel Chris WJ van der Weijden Patrick Schober Robert C Schuit Wiesje M van der Flier Albert D Windhorst Adriaan A Lammertsma Bart NM van Berckel Ronald Boellaard 《Journal of cerebral blood flow and metabolism》2021,41(3):569
Accumulation of amyloid beta (Aβ) is one of the pathological hallmarks of Alzheimer’s disease (AD), which can be visualized using [18F]florbetapir positron emission tomography (PET). The aim of this study was to evaluate various parametric methods and to assess their test-retest (TRT) reliability. Two 90 min dynamic [18F]florbetapir PET scans, including arterial sampling, were acquired (n = 8 AD patient, n = 8 controls). The following parametric methods were used; (reference:cerebellum); Logan and spectral analysis (SA), receptor parametric mapping (RPM), simplified reference tissue model2 (SRTM2), reference Logan (rLogan) and standardized uptake value ratios (SUVr(50–70)). BPND+1, DVR, VT and SUVr were compared with corresponding estimates (VT or DVR) from the plasma input reversible two tissue compartmental (2T4k_VB) model with corresponding TRT values for 90-scan duration. RPM (r2 = 0.92; slope = 0.91), Logan (r2 = 0.95; slope = 0.84) and rLogan (r2 = 0.94; slope = 0.88), and SRTM2 (r2 = 0.91; slope = 0.83), SA (r2 = 0.91; slope = 0.88), SUVr (r2 = 0.84; slope = 1.16) correlated well with their 2T4k_VB counterparts. RPM (controls: 1%, AD: 3%), rLogan (controls: 1%, AD: 3%) and SUVr(50–70) (controls: 3%, AD: 8%) showed an excellent TRT reliability. In conclusion, most parametric methods showed excellent performance for [18F]florbetapir, but RPM and rLogan seem the methods of choice, combining the highest accuracy and best TRT reliability. 相似文献
533.
ERIK WISSNER M.D. S YAMKUMAR DIVAKARA MENON M.D. ANDREAS METZNER M.D. BAS SCHOONDERWOERD M.D. Ph.D. DIETER NUYENS M.D. HISAKI MAKIMOTO M.D. QINGYING ZHANG M.D. SHIBU MATHEW M.D. ALEXANDER FUERNKRANZ M.D. ANDREAS RILLIG M.D. ROLAND RICHARD TILZ M.D. KARL‐HEINZ KUCK M.D. Ph.D. FEIFAN OUYANG M.D. 《Journal of cardiovascular electrophysiology》2012,23(11):1179-1184
Long‐Term Outcome After Substrate‐Based Ablation of LPF VT During SR . Background: Catheter ablation of left posterior fascicular (LPF) ventricular tachycardia (VT) is commonly performed during tachycardia. This study reports on the long‐term outcome of patients undergoing ablation of LPF VT targeting the earliest retrograde activation within the posterior Purkinje fiber network during sinus rhythm (SR). Methods: This study retrospectively analyzed 24 consecutive patients (8 female; mean age 26 ± 11 years) referred for catheter ablation of electrocardiographically documented LPF VT. Programmed stimulation was performed to induce tachycardia, while mapping and ablation was aided by use of a 3D electroanatomical mapping system. Catheter ablation targeted the earliest potential suggestive of retrograde activation within the posterior Purkinje fiber network (retro‐PP) recorded along the posterior mid‐septal left ventricle during SR if LPF VT was noninducible. Results: Overall, 21/24 (87.5%) patients underwent successful catheter ablation in SR targeting the earliest retro‐PP, while 3/24 (12.5%) patients were successfully ablated during tachycardia. In none of the patients, ablation resulted in LPF block. No procedure‐related complications occurred. After a median follow‐up period of 8.9 (4.8–10.9) years, 22/24 (92%) patients were free from recurrent VT. Conclusion: In patients presenting with LPF VT, ablation of the earliest retro‐PP along the posterior mid‐septal LV during SR results in excellent long‐term outcome during a median follow‐up period of almost 9 years. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1179–1184, November 2012) 相似文献
534.
535.
Fiona Heeman Denise Visser Maqsood Yaqub Sander Verfaillie Tessa Timmers Yolande AL Pijnenburg Wiesje M van der Flier Bart NM van Berckel Ronald Boellaard Adriaan A Lammertsma Sandeep SV Golla 《Journal of cerebral blood flow and metabolism》2023,43(3):369
Alzheimer’s disease is characterized by regional reductions in cerebral blood flow (CBF). Although the gold standard for measuring CBF is [15O]H2O PET, proxies of relative CBF, derived from the early distribution phase of amyloid and tau tracers, have gained attention. The present study assessed precision of [15O]H2O derived relative and absolute CBF, and compared precision of these measures with that of (relative) CBF proxies. Dynamic [15O]H2O, [18F]florbetapir and [18F]flortaucipir PET test-retest (TrT) datasets with eleven, nine and fourteen subjects, respectively, were included. Analyses were performed using an arterial input model and/or a simplified reference tissue model, depending on the data available. Relative CBF values (i.e. K1/K1′ and/or R1) were obtained using cerebellar cortex as reference tissue and TrT repeatability (i.e. precision) was calculated and compared between tracers, parameters and clinical groups. Relative CBF had significantly better TrT repeatability than absolute CBF derived from [15O]H2O (r = −0.53), while best TrT repeatability was observed for [18F]florbetapir and [18F]flortaucipir R1 (r = −0.23, r = −0.33). Furthermore, only R1 showed, better TrT repeatability for cognitively normal individuals. High precision of CBF proxies could be due to a compensatory effect of the extraction fraction, although changes in extraction fraction could also bias these proxies, but not the gold standard. 相似文献
536.