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正目前,临床上对于直肠癌常用的影像评估方法有MRI、螺旋CT、PET-CT、直肠腔内超声(ERUS)等。而MRI作为首选检查方式,对肿瘤位置、浸润深度、淋巴结转移、血管侵犯、环周切缘及周围器官侵犯等方面的评估均具有明显优势~([1-2])。通过MRI诊断淋巴结的方法通常是影像科医师逐层浏览每一幅图像,从中识别淋巴结的形状、界限及密度来判断,这种传统方式耗时较长且存在主观偏倚,导致 相似文献
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目的通过Meta分析评价安宁疗护对社区临终患者生活质量的影响。方法计算机检索PubMed、CINAHL、ScienceDirect、MEDLINE、Cochrane Library、SAGE数据库、中国知网、维普中文科技期刊数据库、万方数据库和中国生物医学文献数据库中安宁疗护对社区临终患者的随机对照试验,由2名研究人员独立筛选文献并提取资料,对符合质量标准的随机对照试验进行Meta分析。结果共纳入7篇文献,包括1095名社区临终患者。Meta分析结果显示,安宁疗护可以改善社区临终患者的总体生活质量(SMD=0.48,95%CI0.07~0.88,P=0.02)和情绪功能(SMD=1.27,95%CI0.59~1.95,P<0.001),在改善生活质量的躯体功能、角色功能、认知功能和社会功能水平上差异无统计学意义(P>0.05)。结论安宁疗护能改善社区临终患者的总体生活质量和情绪功能,但对生活质量其他功能的改善情况还需要设计更加规范、多中心、大样本的随机对照试验进一步证实。 相似文献
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目的比较手术夹闭和介入栓塞治疗颅内未破裂动脉瘤的安全性和有效性。方法计算机检索1990至2018年颅内未破裂动脉瘤的所有临床对照研究。两名研究员分别纳入研究、提取数据、质量评价并应用Rev Man5. 0软件进行数据处理。结果最终纳入21篇文献,病例数109114例。Meta分析结果提示:手术夹闭组动脉瘤闭塞率为88. 2%,平均住院时间7. 7天,均高于介入栓塞组的65. 3%和4. 1天,P 0. 05。介入组患者的短期死亡率和致残率分别为0. 61%和2. 1%,均低于手术组的1. 27%和4. 7%,P 0. 05。介入组患者的1年期死亡率和致残率(2. 5%、2. 5%)均与手术组(2. 2%、1. 8%)无明显差异,P 0. 05。漏斗图未发现发表偏倚。敏感性分析结果一致。结论介入栓塞相比于手术夹闭可缩短患者的住院时间,降低患者的短期不良预后发生率。但是动脉瘤的闭塞率较低,1年期预后与手术夹闭无明显差异。据此推测手术夹闭患者的长期预后可能要好于介入栓塞,手术夹闭更适合于年轻患者。 相似文献
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《Brain stimulation》2022,15(2):337-351
BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity. 相似文献
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目的:采用网状Meta分析方法,将普萘洛尔联合其他治疗与各对照治疗措施进行对比。方法:以“普萘洛尔”,“血管瘤”为关键词检索CNKI、VIP、万方数据;以“propranolol”“hemangioma”为关键词检索Cochrane Library、Embase、pubmed。检索期限为建库至2019年6月1日。采用STATA14.0软件Network程序包进行数据分析。结果:共纳入18篇文献,涉及8项治疗措施,共纳入1469例血管瘤患者。网状Meta分析结果显示:4种联合治疗方式与单纯口服普萘洛尔相比疗效均优于单纯口服普萘洛尔治疗。普萘洛尔联合注射平阳霉素、普萘洛尔联合外用噻吗洛尔、普萘洛尔联合敷贴器的有效率均优于对应的注射平阳霉素、外用噻吗洛尔及敷贴器。各治疗措施的有效性排序为:普萘洛尔联合敷贴器>普萘洛尔联合外用噻吗洛尔>普萘洛尔联合口服糖皮质激素>普萘洛尔联合注射平阳霉素>敷贴器照射>外用噻吗洛尔>口服普萘洛尔>注射平阳霉素。结论:对于婴幼儿血管瘤的治疗,普萘洛尔联合治疗措施疗效均优于单纯的口服普萘洛尔治疗,其中普萘洛尔联合敷贴器的疗效最佳。 相似文献
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Tianying Yang Jiawei Li Yichen Jia Chunchen Yang Ruirui Sang Tongyu Zhu Ming Xu Ruiming Rong Cheng Yang 《Translational andrology and urology》2021,10(1):204
BackgroundIn the field of transplantation, inducing immune tolerance in recipients is of great importance. Blocking co-stimulatory molecule using anti-CD28 antibody could induce tolerance in a rat kidney transplantation model. Myeloid-derived suppressor cells (MDSCs) reveals strong immune suppressive abilities in kidney transplantation. Here we analyzed key genes of MDSCs leading to transplant tolerance in this model.MethodsMicroarray data of rat gene expression profiles under accession number in the Gene Expression Omnibus (GEO) database were analyzed. Running the LIMMA package in R language, the differentially expressed genes (DEGs) were found. Enrichment analysis of the DEGs was conducted in the Database for Annotation, Visualization and Integrated Discovery (DAVID) database to explore gene ontology (GO) annotation and their Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Their protein-protein interactions (PPIs) were provided by STRING database and was visualized in Cytoscape. Hub genes were carried out by CytoHubba.ResultsThree hundred and thirty-eight DEGs were exported, including 27 upregulated and 311 downregulated genes. The functions and KEGG pathways of the DEGs were assessed and the PPI network was constructed based on the string interactions of the DEGs. The network was visualized in Cytoscape; the entire PPI network consisted of 192 nodes and 469 edges. Zap70, Cdc42, Stat1, Stat4, Ccl5 and Cxcr3 were among the hub genes.ConclusionsThese key genes, corresponding proteins and their functions may provide valuable background for both basic and clinical research and could be the direction of future studies in immune tolerance, especially those examining immunocyte-induced tolerance. GSE28545相似文献
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