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Qiang Liu Zhongbiao Xu Kaixuan Zhao W. Scott Hoge Xinyuan Zhang Yingjie Mei Qiqi Lu Thoralf Niendorf Yanqiu Feng 《NMR in biomedicine》2022,35(5):e4652
The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague–Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T2-weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T2-weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies. 相似文献
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【摘要】 目的 探讨经动脉栓塞术(transarterial embolization,TAE)治疗食管癌出血的有效性及安全性。方法 收集2018年1月至2020年12月行TAE治疗的14例食管癌出血患者的临床资料、技术成功率、临床成功率,严重并发症情况。评估TAE治疗的有效性及安全性。结果 14例患者中导管成功选择性插入靶动脉并行栓塞患者11例。9例患者接受治疗后未再出现出血征象。出血的主要责任血管为胃左动脉7例,支气管动脉6例和食管固有动脉6例。栓塞材料为微弹簧圈、明胶海绵颗粒及聚乙烯醇颗粒。常见不良反应有疼痛、发热,其中1例患者发生食管瘘。结论 对于内科治疗无效的食管癌出血,TAE可以起到良好的疗效。食管瘘作为术后的严重并发症,需特别注意预防。对于胸段食管癌及食管胃交界处癌,最常见的责任血管为胃左动脉、支气管动脉及食管固有动脉。 相似文献
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《结合医学学报(英文版)》2022,20(6):497-513
BackgroundFiliform needle acupuncture (FNA), the most classical and widely applied acupuncture method based on traditional Chinese medicine theory, has shown a promising effect in the treatment of allergic rhinitis (AR).ObjectiveTo evaluate the efficacy, safety, cost-effectiveness, and patient preference of FNA in the treatment of AR by comparing FNA with sham acupuncture, no treatment, and conventional medication.Search strategyEight electronic databases were systematically searched from inception to October 14, 2021. Additional studies were acquired from clinical trial registration platforms and reference lists.Inclusion criteriaRandomized controlled trials were included if they compared FNA with either sham acupuncture, no treatment or conventional medication for AR.Data extraction and analysisTwo researchers extracted data independently of each other using a predesigned data acquisition form, and results were cross-checked after completion. The primary outcome was symptom score (Total Nasal Symptom Score or Visual Analogue Scale), and the secondary outcomes were the AR control questionnaire, quality of life (QoL) score (Different versions of Rhinoconjunctivitis Quality of Life Questionnaire), medication score (use of rescue medication), mental health score, total IgE, adverse event rate, clinical economic indicators, and patient satisfaction score. Standardized mean difference (SMD) or mean difference (MD) with 95% confidence interval was used to calculate the effect size for continuous data, while risk ratio with 95% CI was used for dichotomous data.ResultsThirty studies were included in this review. Compared with sham acupuncture, FNA significantly reduced the symptom score (SMD: ?0.29 [?0.43, ?0.15]), AR’s impact on QoL (SMD: ?0.23 [?0.37, ?0.08]) and medication score (SMD: ?0.3 [?0.49, ?0.11]). Compared with no treatment, FNA dramatically reduced the symptom score (SMD: ?0.8 [?1.2, ?0.39]) and AR’s impact on QoL (SMD: ?0.82 [?1.13, ?0.52]). There were no increased rates of adverse events with FNA compared to sham acupuncture and no treatment. FNA increased patient satisfaction and may be cost-effective. Most pieces of evidence from the above two comparisons were of high confidence. Moreover, FNA significantly outperformed conventional medication in reducing the symptom score (SMD: ?0.48 [?0.85, ?0.1]) and displayed a lower rate of adverse events, but the quality of evidence was very low.ConclusionFNA is an effective and safe intervention for AR and can help with symptom relief, QoL improvement, reducing medication usage, and increasing patient satisfaction. Further studies are needed to verify its cost-effectiveness and superiority over conventional medication and the best therapeutic strategies. 相似文献