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原发性胸椎原始神经外胚层肿瘤的动态增强MRI表现 总被引:5,自引:0,他引:5
目的 初步探讨原始神经外胚层肿瘤(PNET)的动态增强MRI表现,以及对其诊断及鉴别诊断的价值。方法 用动态增强MRI方法对已手术和病理证实的2例胸椎PNET行3次MR检查并进行前瞻性研究。结果 在信号强度-时间和对比增强率.时间曲线上,2例PNET3次检查均表现为快升慢降型,即肿瘤早期就开始迅速增强,上升峰极陡,60~120s即达到高峰水平,然后保持平坦,3.5min内未见明显下降曲线。结论 动态增强MRI扫描能帮助对PNET进行早期诊断和鉴别诊断,从而为临床选择治疗方案及估计预后提供较为可靠的依据。 相似文献
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深部脑白质缺血影像表现与MTHFR基因多态性关系的探讨 总被引:1,自引:0,他引:1
目的:探讨MTHFR的纯合突变TT型基因是否为诱发皮层下深部脑白质缺血的危险因子,并证实皮层下深部脑白质缺血影像表现与MTHFR基因C/T多态性的关系。资料与方法:选择影像表现符合皮层下深部脑白质缺血诊断标准者30例,对照组30例为影像表现正常者,运用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-RFLP)检测两组MTHFR基因多态性。结果:采用χ^2检验,得出MTHFR基因纯合突变TT型在病变组与对照组比较差异有显著性(χ^2=5.0794,P<0.05),病变组TT型较对照组显著升高,说明MTHFR的纯合突变TT型可能是诱发深部脑白质缺血的危险因素。运用成组设计两样本比较的秩和检验,得出TT型和非TT型患者在影像表现的分级程度上有差别,携带TT型基因者影像表现分级重。结论:MTHFR纯合突变TT型基因是深部脑白质缺血发病的危险因子,且TT型基因与深部脑白质缺血的易感性和影像表现呈明显正相关。 相似文献
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多层螺旋CT与选择性冠状动脉造影对照研究及其临床应用 总被引:50,自引:2,他引:48
目的 评价冠状动脉多层螺旋CT血管造影(MSCTA)的临床应用价值。方法 25例患者均行冠状动脉MSCTA与选择性冠状动脉造影(SCA),分析右冠状动脉、左冠状动脉主干、前降支和回旋支的通畅性,狭窄发生的部位和严重程度。将MSCTA与SCA结果对照,初步评价MSCTA的临床应用价值。结果 71支MSCTA显示无狭窄的冠状动脉支中,68支与SCA一致;29支显示狭窄的动脉支中,19支与SCA一致。其阴性预测值和阳性预测值分别为95.8%和65.5%;敏感度、特异度和准确度分别为86.4%、87.2%、87,0%。结论 MSCTA作为微创性检查,是评价冠状动脉病变和变异的重要的筛选手段。 相似文献
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目的通过绘制时间信号强度曲线,探讨 MRI 快速序列动态增强在前列腺癌诊断及鉴别诊断中的价值。方法对5例无泌尿系症状健康对照者、13例经病理证实的前列腺癌及36例前列腺增生行 MR 平扫、动态增强及延迟扫描,测量并计算病灶和正常组织的相对信号强度值,并绘制正常周围带、前列腺癌与增生三者的时间信号强度曲线。结果正常周围带轻度强化,并缓慢上升至晚期达峰值;36例前列腺增生早期明显强化并逐渐上升至中晚期达峰值后缓慢下降;13例前列腺癌中9例早期明显强化,并快速下降,4例 T_2WI 像上弥漫性病灶呈现中晚期强化。结论正常周围带、前列腺癌及前列腺增生的动态强化方式明显不同,应用动态增强扫描可对前列腺癌的诊断与鉴别诊断起积极作用。 相似文献
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为了实现超声对比剂(也称超声造影剂)高效、合理、安全、规范化输注,国内相关医护专家总结了国内外文献证据及临床经验,按照循证医学原则充分讨论后,制订了该共识,旨在为我国超声对比剂安全输注的规范化和标准化提供参考意见。共识介绍了超声对比剂的应用现状和安全性、相关法规与流程,造影前、中、后的规范化护理,并提出16条推荐意见。提出目前国内批准上市使用的超声对比剂安全性高,建议医护人员根据最新说明书或专家共识进行配药和给药,并从造影室管理、风险预案、人员资质等方面予以规范。 相似文献
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ABSTRACT: BACKGROUND: Introducing a new method into family planning programs requires careful attention to ensure it meets an actual need and has a positive effect on program goals. The Standard Days Method(R) is a fertility awareness-based method of family planning that is being introduced into family planning programs in countries around the world. It is different from other methods offered by programs, and may bring new couples into family planning, and increase contraceptive prevalence. The study assesses the effect on contraceptive use and prevalence of Introducing Standard Days Method into existing family planning services in whole regions of India, Peru, and Rwanda. METHODS: In collaboration with the Ministry of Health, health providers were given a contraceptive update on all methods, then trained in counseling on Standard Days Method. Efforts were made to promote demand in the context of informed choice. Routine monthly service statistics in control and intervention areas were used to assess the effect of Standard Days Method introduction at the clinic level; baseline and endline household-based surveys were undertaken to obtain results at the community level (n > 3400 women at endline). RESULTS: Demand for the method is evident in countries with different levels of contraceptive prevalence. The method attracts couples new to family planning, and introducing it into services may increase overall contraceptive prevalence. CONCLUSIONS: Introducing Standard Days Method into existing family planning has the potential of benefiting men and women in diverse settings and populations. This study illustrates the critical role of evidence in scaling up a health innovation. 相似文献
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Repair of erosions in rheumatoid arthritis does occur. Results from 2 studies by the OMERACT Subcommittee on Healing of Erosions 总被引:4,自引:0,他引:4
Sharp JT Van Der Heijde D Boers M Boonen A Bruynesteyn K Emery P Genant HK Herborn G Jurik A Lassere M McQueen F Østergaard M Peterfy C Rau R Strand V Wassenberg S Weissman B;Subcommittee on Healing of Erosions of the OMERACT Imaging Committee 《The Journal of rheumatology》2003,30(5):1102-1107
The committee was charged with determining whether healing of erosions in rheumatoid arthritis (RA) occurs. Two exercises were performed: The first asked the committee members, as a panel of experts, to express agreement or disagreement with the presence of improvement and features of bone reaction to injury in images submitted by members as examples of healing. The second presented panel members with 28 pairs of serial images, 14 chosen to illustrate progression and 14 chosen to illustrate repair. Agreement was tested on 8 items: global judgment on which image in the pair was better, relative size of the erosion in the 2 images, judgment on which image was first, presence and extent of sclerosis, cortication, filling-in, remodeling, and reconstituting normal structure. Our results showed good agreement, among the 15 respondents, on global assessment of which image was better and which image showed the smaller erosion. Correct assignment of sequence was only slightly better than expected by chance (in 65% of the cases). Agreement was poor regarding the presence of morphologic features of bone repair. A majority of a panel of experts agreed on which 2nd images in a set of paired, serial images represented improvement and which showed progression based on global assessment of which was better and on size of erosion. Features of bone repair were not distinctive and did not enable the panel to deduce the correct sequence of the serial images. This study provides evidence that repair of bone damage in RA does occur, resulting in some degree of improvement, which was recognized by a majority of a panel of experts. 相似文献
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