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排序方式: 共有480条查询结果,搜索用时 15 毫秒
101.
102.
目的完善造影中的摄影体位,显示最佳的造影效果。方法对50例泌尿系梗阻伴积水患者,在IVP中采取先传统仰卧位,必要时俯卧位的造影方法,对其先后两种方法的显影效果进行比较。结果先仰卧位再俯卧位摄影后,肾盂肾盏显影率提高20%,P<0.05;肾盂-输尿管连接部及各段显影率提高18%,P<0.05。结论排泄性尿路造影,必要时采取俯卧位摄影,能弥补传统造影体位的不足,使梗阻部位在仰卧前后位无法显示的解剖机构和病变满意显示出来,是泌尿系梗阻时,肾盂肾盏及解压后输尿管全程显影最好的补充体位。方法简便,值得常规鉴用。 相似文献
103.
Quantitative and qualitative analysis of both generated reactive oxygen species (ROS) and mitochondrial membrane potential cannot be detected simultaneously. We here introduce a simple, new double staining method. We have successfully used this for several years utilizing cerium for ROS detection and JC-1 staining to assess the mitochondrial membrane potential. The resultant signals on laser confocal images can be localized in the same cells and can easily quantify them. We used a confocal microscope along with our new, combined staining method to both visualize mitochondrial membrane potential (DeltaPsim) and imaged ROS. These were quantified by JC-1 staining and by cerium ions with reflectance in a method modified in our laboratory. To test this double labeling technique we used PC 12 cells subjected to 1 h hypoxia and 24h re-oxygenization. We are able to produce a quantitative analysis of red/green signals of JC-1 that reflected the energy state of the cells. Cerium reflectance correlates with the amount of ROS release in the same cells. Significant differences have been calculated after hypoxia and re-oxygenation in both modality of the cell staining. The red/green ratio was 18.2+/-9.3 (n=30) in normoxic cells versus 1.65+/-0.9 (n=30) in the hypoxia/re-oxygenation group (p<0.05). In the same randomly selected cells the average cerium reflectance signal intensity was 2.5+/-1.2 (n=30) in the control group while 5.8+/-3.1 (n=30) in the hypoxia/re-oxygenation group (p<0.05). This assay, by characterizing hypoxic injury and re-oxygenization induced ROS production, offers a qualitative and quantitative method to detect the consequences of oxidative stress in experimental conditions and to detect different cell protective strategies. 相似文献
104.
Jinlong Shi Author Vitae Zhigang Luo Author Vitae 《Computers in biology and medicine》2010,40(8):723-732
Gene expression data are the representation of nonlinear interactions among genes and environmental factors. Computing analysis of these data is expected to gain knowledge of gene functions and disease mechanisms. Clustering is a classical exploratory technique of discovering similar expression patterns and function modules. However, gene expression data are usually of high dimensions and relatively small samples, which results in the main difficulty for the application of clustering algorithms. Principal component analysis (PCA) is usually used to reduce the data dimensions for further clustering analysis. While PCA estimates the similarity between expression profiles based on the Euclidean distance, which cannot reveal the nonlinear connections between genes. This paper uses nonlinear dimensionality reduction (NDR) as a preprocessing strategy for feature selection and visualization, and then applies clustering algorithms to the reduced feature spaces. In order to estimate the effectiveness of NDR for capturing biologically relevant structures, the comparative analysis between NDR and PCA is exploited to five real cancer expression datasets. Results show that NDR can perform better than PCA in visualization and clustering analysis of complex gene expression data. 相似文献
105.
目的:评价可视化针刀治疗的可行性和安全性.方法:超声引导下对52例软组织损伤及骨关节疾病患者进行针刀治疗,采用疼痛视觉模拟评分法(VAS),观察治疗前后VAS评分变化,并采用改良HSS膝关节评分法、Constant-Murley肩功能评定标准对膝关节炎和肩周炎患者的关节功能进行评定比较.结果:治疗后患者VAS评分均较前明显改善(6.560±0.893 vs 1.058±0.857,P<0.05);1次治疗痊愈率达48.1% (25/52),总有效率达98.1%(51/52);治疗后HSS评分、Constant-Murley评分均明显提高(均P<0.05);随访均未见感染、神经损伤等并发症.结论:超声引导下针刀治疗软组织损伤和骨关节疾病安全、有效,值得临床推广. 相似文献
106.
目的:本文阐述了药物化学图形资源系统开发意义、设计方法及构建网络应用平台的全过程。方法:本系统以Eclipse-JAVA语言平台作为开发环境,以SQL Server 2005数据库作为图形数据存储工具,利用面向对象技术和图形处理技术,设计了基于B/S结构的"药物化学结构式图形资源系统"。结果:本系统实现了药物化学结构式图形及信息的分类存储、按药物的名称、性状等信息分类的快速检索及按药效分类的模糊查询等功能。结论:系统具有用户界面友好,使用便捷,内容丰富、支持多种查询方式等特点,为药学工作者带来了方便。 相似文献
107.
GOPubMed:基于GO和MeSH的信息检索与分析研究 总被引:7,自引:2,他引:5
GOPubMed是一种基于PubMed的结果可视化和后处理类型的智能搜索引擎.从工作原理、关键技术以及扩展功能3个方面对其性能进行解析.研究显示,GOPubMed利用基于语义网的语义分类工具--GO(Gene Ontology,基因本体)和MeSH,对PubMed检索结果进行分类,帮助用户快速地找出最相关的命中文献,实现语义网与生物医学信息检索的完美结合,并能对检索结果从多角度进行可视化统计分析. 相似文献
108.
Kim Nylund Svein Фdegaard Trygve Hausken Geir Folvik Gǖlen Arslan Lied Ivan Viola Helwig Hauser Odd-Helge Gilja 《World journal of gastroenterology : WJG》2009,15(11):1319-1330
In the last two decades, there has been substantial development in the diagnostic possibilities for examining the small intestine. Compared with computerized tomography, magnetic resonance imaging, capsule endoscopy and double-balloon endoscopy, ultrasonography has the advantage of being cheap, portable, flexible and user- and patient-friendly, while at the same time providing the clinician with image data of high temporal and spatial resolution. The method has limitations with penetration in obesity and with intestinal air impairing image quality. The flexibility ultrasonography offers the examiner also implies that a systematic approach during scanning is needed. This paper reviews the basic scanning techniques and new modalities such as contrast-enhanced ultrasound, elastography, strain rate imaging, hydrosonography, allergosonography, endoscopic sonography and nutritional imaging, and the literature on disease-specific findings in the small intestine. Some of these methods have shown clinical benefit, while others are under research and development to establish their role in the diagnostic repertoire. However, along with improved overall image quality of new ultrasound scanners, these methods have enabled more anatomical and physiological changes in the small intestine to be observed. Accordingly, ultrasound of the small intestine is an attractive clinical tool to study patients with a range of diseases. 相似文献
109.
110.
人淋巴结支架中血管三维结构重建的病理意义 总被引:1,自引:0,他引:1
淋巴结支架包括血管、淋巴管和网状支架。目前国内对人淋巴结支架三维结构的研究不多见。淋巴结内的血管具有特殊性,在整个支架系统中的作用相对重要一些,也是研究的重点。利用计算机重建其组织切片的三维结构,建立一个直观又清晰的血管三维关系图,为病理诊断及临床治疗提供可靠的依据。 相似文献