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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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Matthias Knefel PhD Elisabeth L. Zeilinger PhD Simone Lubowitzki PhD Katharina Krammer MSc Matthias Unseld MD Rupert Bartsch MD Thorsten Fuereder MD Ulrich Jäger MD Barbara Kiesewetter MD Maria Krauth MD Markus Raderer MD Philipp B. Staber MD Peter Valent MD Alexander Gaiger MD 《Cancer》2023,129(21):3466-3475
Background
Survival in cancer patients is associated with a multitude of biological, social, and psychological factors. Although it is well established that all these factors add to overall mortality, it is not well understood how the predictive power of these parameters changes in a comprehensive model and over time.Methods
Patients who attended the authors’ outpatient clinic were invited to participate. The authors followed 5180 mixed cancer patients (51.1% female; mean age, 59.1 years [SD = 13.8]) for up to 16 years and analyzed biological (age, sex, cancer site, anemia), psychological (anxiety, depression), and social variables (marital status, education, employment status) potentially predicting overall survival in a Cox proportional hazards model.Results
The median survival time for the entire sample was 4.3 years (95% confidence interval, 4.0–4.7). The overall survival probabilities for 1 and 10 years were 76.8% and 38.0%, respectively. Following an empirical approach, the authors split the time interval into five periods: acute, subacute, short-term, medium-term, and long-term. A complex pattern of variables predicted overall survival differently in the five periods. Biological parameters were important throughout most of the time, social parameters were either time-independent predictors or tended to be more important in the longer term. Of the psychological parameters, only depression was a significant predictor and lost its predictive power in the long-term.Conclusions
The findings of this study allow the development of comprehensive patient-specific models of risk and resilience factors addressing biopsychosocial needs of cancer patients, paving the way for a personalized treatment plan that goes beyond biomedical cancer care. 相似文献25.
摘要:目的 探讨儿童肺炎克雷伯菌血流感染(Klebsiella pneumoniae bloodstream infection, KPBSI)临床特征及肺炎克雷伯
菌(Klebsiella pneumoniae, KP)对常用抗菌药物的敏感性,为儿童KPBSI合理治疗提供参考。方法 回顾性分析2014年1月至2019
年12月在重庆医科大学附属儿童医院住院的KPBSI患儿临床资料。结果 共纳入110例患儿,64例(58.2%)为院内感染,72例
(65.5%)有基础疾病,以血液系统肿瘤最多见。110例患儿PRISM Ⅲ评分为16.0(7.0~20.8),其中74例(67.3%)发生脓毒症,15例
(13.6%)发生脓毒性休克,18例(16.4%)发生呼吸衰竭,15例(13.6%)需有创机械通气,院内死亡共13例(11.8%)。KP菌株对阿米卡
星、碳青霉烯类抗菌药物敏感率>90%,对头孢噻肟、头孢曲松和头孢他啶的敏感率分别为58.3%、60.9%和70.9%,对头孢哌
酮/舒巴坦和哌拉西林/他唑巴坦的敏感率分别为59.5%和82.7%。检出ESBLs+菌株39株(39/86,45.3%),耐碳青霉烯类肺炎克雷
伯菌(CRKP)菌株10株(10/110,9.1%),ESBLs+KP菌株和CRKP在各年龄组间分布无统计学差异。结论 儿童KPBSI多见于有基
础疾病的患儿,脓毒症、脓毒性休克和呼吸衰竭发生率高;KP菌株对头孢他啶和哌拉西林/他唑巴坦敏感性较高,可经验性治
疗轻症KPBSI患儿。 相似文献
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Clinical Rheumatology - This study aimed to detect the expression of progranulin (PGRN) and elucidate associations with clinical features in dermatomyositis (DM) patients with anti-melanoma... 相似文献
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宫腔积液指宫腔内液体积存(积水、积血或积脓),是绝经后女性常见体征之一,常于超声检查时发现。持续宫腔积液患者,需宫腔镜检查寻找病因。本文报道1例以宫腔积液为首发症状,经宫腔镜检查确诊为胃型宫颈腺癌的患者。通过病例回顾并文献复习,以期为更多绝经后宫腔积液及宫颈病变的诊断提供参考,避免漏诊及误诊。1病例资料患者67岁,女,主因"绝经18年,不规则阴道出血2月"于2020年5月就诊于首都医科大学附属北京妇产医院妇科微创中心。 相似文献
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随着人类基因组测序、生物大数据信息分析、分子病理检测和人工智能辅助病理诊断等技术进步及其应用, 临床医学发展迈向精准诊疗时代。这一时代背景下, 传统诊断病理学迎来前所未有的历史机遇, 正在向"下一代诊断病理学(next-generation diagnostic pathology)"迈进。下一代诊断病理学以病理形态和临床信息为诊断基础, 以分子检测与生物信息分析、智慧制样与流程质控、智能诊断与远程会诊、病灶活体可视化与"无创"病理诊断等创新前沿交叉技术为主要特征, 以多组学和跨尺度整合诊断为病理报告内容, 实现对疾病的"最后诊断", 并预测疾病演进和结局、建议治疗方案和评估治疗反应, 形成新的疾病诊断"金标准"。未来, 需要激发病理学科创新活力, 加快下一代诊断病理学成熟和应用, 重塑病理学科理论和技术体系, 发挥诊断病理学在疾病"防、诊、治、养"等过程中的重要作用, 促进临床医学进一步发展, 服务健康中国战略。 相似文献
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Zyuz’kov G. N. Zhdanov V. V. Miroshnichenko L. A. Polyakova T. Yu. Stavrova L. A. Simanina E. V. Minakova M. Yu. Agafonov V. I. Churin A. A. 《Bulletin of experimental biology and medicine》2022,173(5):615-619
Bulletin of Experimental Biology and Medicine - The psychopharmacological effects of a stimulator of functions of progenitor cells of the nervous tissue STAT3 inhibitor (STAT3 Inhibitor XIV, LLL12)... 相似文献