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991.
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G. Shi 《International journal of hyperthermia》2013,29(6):625-636
The design and performance of annular antenna arrays with reflectors is presented. Arrays with three shapes of reflectors are analysed and simulated. These include the corner reflector, the circular reflector and the elliptical reflector. Power-density distributions within the annular arrays with and without reflectors are obtained by using the FDTD method. Also, the image theory method is used to verify the FDTD results in one case. By comparing the power-density distribution pattern of all four of the array designs (three with different reflectors, one without reflector), it is readily seen in each case that the array with reflectors yields better power-efficiency than the array without reflectors and the elliptical reflector yields the best performance. Comparisons of each array are made using 4, 6 and 8 antennae in the annular array. By using the optimized results of the elliptical reflector, the requirement for the input-power level to each antenna is greatly reduced. 相似文献
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To summarize the clinicopathological features, therapeutic regimens, and outcomes for patients with primary testicular lymphoma (PTL), we retrospectively reviewed the medical records of 13 patients diagnosed with PTL between 2001 and 2012 at our hospital. Average age at diagnosis was 62.2 ± 13.9 years, and all patients presented with painless testicular swelling. Diffuse large B-cell lymphoma was the dominant histotype (69.2 %). All 13 patients were treated with inguinal orchiectomy and received chemotherapy and/or radiotherapy. Complete follow-up data were available for 10 patients with an average follow-up duration of 28.4 ± 30.9 months. Seven patients were evaluated as Ann Arbor stage I or II, and three as stage III or IV. Eight patients were found to have hypoechogenic and hypervascular signals in the testis on ultrasound examination. Complete remission was achieved in six patients, and four patients who were still undergoing chemotherapy during the last follow-up showed no signs of relapse. Of the 10 patients with complete follow-up records, three had relapses, which occurred in the CNS, epiglottis, and the nasal cavity. Time to relapse in these cases was 2, 7, and 11 months, respectively (3/10). The mean progression-free survival was 22.57 months (range 1.1–101.9 months). 相似文献
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The accuracy of metabolite concentrations measured using in vivo proton (1H) MRS is enhanced following correction for spin–spin (T2) relaxation effects. In addition, metabolite proton T2 relaxation times provide unique information regarding cellular environment and molecular mobility. Echo‐time (TE) averaging 1H MRS involves the collection and averaging of multiple TE steps, which greatly simplifies resulting spectra due to the attenuation of spin‐coupled and macromolecule resonances. Given the simplified spectral appearance and inherent metabolite T2 relaxation information, the aim of the present proof‐of‐concept study was to develop a novel data processing scheme to estimate metabolite T2 relaxation times from TE‐averaged 1H MRS data. Spectral simulations are used to validate the proposed TE‐averaging methods for estimating methyl proton T2 relaxation times for N‐acetyl aspartate, total creatine, and choline‐containing compounds. The utility of the technique and its reproducibility are demonstrated using data obtained in vivo from the posterior‐occipital cortex of 10 healthy control subjects. Compared with standard methods, distinct advantages of this approach include built‐in macromolecule resonance attenuation, in vivo T2 estimates closer to reported values when maximum TE ≈ T2, and the potential for T2 calculation of metabolite resonances otherwise inseparable in standard 1H MRS spectra recorded in vivo. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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目的 观察菊花总黄酮在体外条件下对泪腺上皮细胞中雄激素受体(Androgen Receptor,AR)的调控作用及对下游的核因子κB(Nuclear Factor kappa B,NF-κB)、转化生长因子-β1(transforming growth factor-beta1,TGF-β1)的表达影响。方法 以过氧化氢(H2O2)诱导泪腺上皮细胞凋亡,建立细胞模型,设立无雄激素培养空白对照组、含雄激素培养对照组、无雄激素培养黄酮治疗组。以MTT法摸索含药血清最佳干预加入量;免疫印迹实验(Western Blot)以及实时荧光定量PCR法(Quantitative Real-Time PCR,qPCR)检测泪腺上皮细胞中AR、NF-κB及TGF-β1的表达情况;并应用雄激素受体阻断剂氟他胺进行AR阻断后再次检测上述指标 。结果 MTT法检测后计算得出含药血清干预细胞的最终浓度为13.2%;无雄激素培养黄酮治疗组及含雄激素培养对照组中AR、NF-κB及TGF-β1的表达增强,与空白对照组对比有显著差异(P<0.01);无雄激素培养黄酮治疗组中NF-κB表达量比含雄激素培养对照组表达量低,两者间的差异有统计学意义。氟他胺及含药血清干预后,无雄激素培养黄酮治疗组及含雄激素培养对照组中AR及NF-κB的表达未见提高,无统计学意义。结论 菊花总黄酮对泪腺上皮细胞可能存在拟雄激素效应,从而使AR、NF-κB表达增加,并通过上调TGF-β1的表达,可能起到在泪腺局部的抗炎作用。 相似文献
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