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31.
Behcet’s disease is generally defined by oral and genital ulcers and uveitis. It is also known as a recurrent multisystemic and inflammatory disease. It is mostly seen in Mediterranean countries and the Far East.The aetiology of Behcet’s disease is associated with viral, toxic, bacterial and immunological factors. It was defined in 1963 as an auto-immune disease caused by auto-antibodies against the oral mucosa. Vascular involvement is 2–7% and it is usually seen in patients between the ages of 20 and 40 years.Behcet’s disease is a non-specific arterial and venous vasculitis.1-8 Proximal and distal anastomotic aneurysm formation after surgery is not rare one to 12 months postoperatively. Recurrent surgical interventions increase the risk of mortality and morbidity.9,10 Cardiovascular involvement in Behcet’s disease includes pericarditis, coronary arterial disease, cardiomyopathy and valvular dysfunction.11 The aim of this study was to report our experience of cardiovascular involvement with asymptomatic Behcet’s disease.  相似文献   
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Interactive 3D editing tools for image segmentation   总被引:4,自引:0,他引:4  
Segmentation is an important part of image processing, which often has a large impact on quantitative image analysis results. Fully automated operator independent segmentation procedures that successfully work in a population with a larger biological variation are extremely difficult to design and usually some kind of operator intervention is required, at least in pathological cases.We developed a variety of 3D editing tools that can be used to correct or improve results of initial automatic segmentation procedures. Specifically we will discuss and show examples for three types of editing tools that we termed: hole-filling (tool 1), point-bridging (tool 2), and surface-dragging (tool 3). Each tool comes in a number of flavors, all of which are implemented in a truly 3D manner. We describe the principles, evaluate efficiency and flexibility, and discuss advantages and disadvantages of each tool. We further demonstrate the superiority of the 3D approach over the time-consuming slice-by-slice editing of 3D datasets, which is still widely used in medical image processing today. We conclude that performance criteria for automatic segmentation algorithms may be eased significantly by including 3D editing tools early in the design process.  相似文献   
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Brain Imaging and Behavior - In many patients, ostensible idiopathic attention deficit-hyperactivity disorder (ADHD) may actually stem from covert prenatal alcohol exposure (PAE), a...  相似文献   
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目的:探讨基质金属蛋白酶‐9(MMP‐9)、白细胞介素‐6(IL‐6)和白细胞介素‐10(IL‐10)与脑动脉粥样硬化斑块不稳定性以及脑梗死的关系。方法选择急性脑血管病患者56例,其中反复短暂性脑缺血发作(TIA)16例,急性脑梗死40例。对照组为21例健康体检者。所有缺血性脑血管病患者均经头CT血管造影(CTA)检查或颈部血管超声证实存在不稳定斑块,且发病机制考虑与不稳定斑块破裂有关。采用ELISA方法检测各组血清MMP‐9、IL‐6和IL‐10水平并进行比较。结果急性脑梗死组患者血清中MMP‐9、IL‐10水平分别为(137.10±69.38)ng/mL和(39.16±32.82)pg/mL,TIA组患者血清中MMP‐9、IL‐10水平分别为(119.79±65.54)ng/mL和(33.00±21.36)pg/mL,均明显高于对照组〔分别为(65.42±36.81)ng/mL和(19.83±12.16)pg/mL〕;脑梗死组患者血清MMP‐9及IL‐10水平均高于TIA组(均P<0.05)。各组间IL‐6水平差异无统计学意义(均P>0.05)。结论MMP‐9和IL‐10水平升高可能与动脉粥样硬化不稳定斑块破裂以及脑梗死灶形成有关。  相似文献   
37.
deShazo  RD; Daul  CB; Andes  WA; Bozelka  BE 《Blood》1985,66(4):993-998
Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity.  相似文献   
38.
Breast cancer is the most common cause of cancer death in women in this country. Until recently, the traditional treatment has been radical surgery with or without radiation therapy for patients with primary breast cancer, and palliative endocrine therapy followed by chemotherapy for patients with advanced disease. These treatments have met with limited effectiveness in terms of eradicating the disease. Studies in the past decade have given cause for optimism for breast cancer patients. Adjuvant systemic therapy after local treatment appears promising for certain subsets of patients with primary breast cancer. The development of estrogen receptor assays has markedly changed our approach to the disease and improved patient care. Estrogen receptor is an important prognostic factor and is useful in planning appropriate therapy for patients with primary breast cancer as well as those with advanced disease. Further research is urgently needed to improve the dismal survival of certain women with this common malignancy.  相似文献   
39.
[目的]用荧光DDRT-PCR技术寻找低剂量环境化学污染物(ECPs)过氧化氢(H_2O_2)、甲醛(FA),三氯乙烯(TCE)诱导细胞适应性反应差异表达的基因,为进一步研究低剂量的环境化学污染物(ECPs)诱导机体的生物学效应及其机理提供科学依据。[方法]依据H_2O_2、FA、TCE对细胞毒性的剂量反应关系,建立适应性反应的模型。然后用荧光DDRT-PCR寻找对照组、低剂量组、高剂量组,适应性反应组差异表达的基因,并鉴定和验证部分差异表达的基因。[结果]按照对照组、低剂量组、高剂量组、适应性反应组处理细胞后,DDRT-PCR结果显示各处理组与对照组比较:H_2O_2有60个差异条带、FA有61个,TCE有52个。选择差异比较明显的条带进行2次PCR,然后通过进一步克隆、测序、同源性比较发现一些已知基因如BCL-2、EIF3S5、NDUFS4、RPS10等。[结论]低剂量环境化学污染物诱导机体的适应性反应可能有维持细胞稳态、抗氧化系统、DNA损伤修复级激活细胞信号分子等过程的参与。  相似文献   
40.
目的研究食管鳞癌患者外周血T淋巴细胞亚群的变化特点。方法采用流式细胞技术,对108例食管鳞癌患者(食管鳞癌组)术前检测其外周血T淋巴细胞亚群水平,并与50例健康献血者(对照组)对比,分析食管鳞癌患者T淋巴细胞亚群的变化特点。结果(1)与对照组比较,食管鳞癌组患者外周血CD3^+ 、NK细胞水平差异无统计学意义(P=0.890;P=0.320);CD4^+和CD8^+水平显著增高(P=0.001;P〈0.001),由于CD8^+增高的程度大于CDZ增高的程度,使得CDgCDs~较对照组降低(P〈0.001)。(2)早期食管鳞癌患者外周血CD4^+/CD8^+低于对照组,但差异无统计学意义(P=0.112);中晚期食管鳞癌患者CDgCDs~进一步降低,与对照组比较差异有统计学意义(P〈0.001),但与早期食管鳞癌患者相比,差异无统计学意义(P=0.218)。(3)有淋巴结转移食管鳞癌患者CD4^+和CD4^+/CD8^+均低于无淋巴结转移患者(P均〈0.001),CD8^+和NK细胞均高于无淋巴结转移患者,差异均有统计学意义(P=0.002;P=0.005)。结论食管鳞癌患者存在免疫功能低下,随着肿瘤的进展免疫功能进一步受到削弱;监测CD4^+/CD8^+的变化可作为食管鳞癌病情进展的标志之一。  相似文献   
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