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151.
CD33分子为一种跨膜受体,主要存在于血液、骨髓和淋巴细胞中.它属于免疫球蛋白超家族成员,并且是能够结合唾液酸的免疫球蛋白样的凝集素家族成员.在这一膜受体内部存在免疫受体酪氨酸抑制基序(ITIM).由于ITIM能够特异性的与酪氨酸磷酸酶shp-1和shp-2结合并向胞内传递抑制性信号,从而达到抑制细胞活性的目的,所以CD33分子主要在临床上作为一种靶位点用于急性骨髓系白血病(AML)的治疗.  相似文献   
152.
阐述了MVC模式的项目开发原理及优势,探讨了基于MVC模式的软件开发流程,并依据MVC的基本思想设计了一个Web应用系统——随书光盘发布系统的功能模型;最后将MVC模式应用于JSP,开发实现了该系统。  相似文献   
153.
目的:通过对4周负重游泳运动前、后小鼠脾脏CD4+CD25+Treg表达水平变化及相关细胞因子IL-2、IL-10和TGF-β1水平变化的分析,探讨和研究有氧耐力运动对小鼠脾脏CD4+CD25+Treg表达及细胞因子IL-2、IL-10和TGF-β的影响。方法:KM种雄性小鼠100只随机分为对照组(50只)和运动组(50只)。运动各组分别按运动方案进行45min的负重(5%体重)游泳运动每天1次,每周6次。分别于实验前、每周末次运动后24h,处死小鼠,摘取脾脏和胸腺、采集血样。计算脾指数和胸腺指数,流式细胞仪检测小鼠脾脏CD4+CD25+Treg的表达,ELISA法测定血清IL-2、IL-10和TGF-β含量。结果:在4周负重游泳运动过程中,运动组小鼠脾指数在第1周末增加并在随后2、3、4周表现出下降的趋势,胸腺指数表现为逐周减少。运动组小鼠脾脏CD4+CD25+Treg的表达率表现为逐周增高,运动3周组、4周组高于运动0周组和对照组(P<0.05)。运动2周组和3周组血清IL-2水平升高,高于对照组(P<0.05);运动3周组和4周组血清IL-10和TGF-β1水平高于对照组(P<0.05)。结论:4周有氧耐力游泳运动可延缓小鼠脾脏生长,加快胸腺萎缩,进而影响免疫器官的发育和功能。4周有氧耐力游泳运动可诱导小鼠T细胞活化,脾脏CD4+CD25+Treg表达水平提高,血清IL-10和TGF-β1水平升高,诱导免疫偏移。  相似文献   
154.
Celiac disease (CD) is a type of intestinal malabsorption syndrome, in which the patients are intolerant to the gliadin in dietary gluten, resulting in chronic diarrhea and secondary malnutrition. The disease is common in Europe and the United States, but only sporadic reports are found in East Asia including China. Is CD really rare in China? We examined 62 patients by capsule endoscopy for chronic diarrhea from June 2003 to March 2008. Four patients with chronic diarrhea and weight loss were diagnosed to have CD. Under the capsule endoscopy, we observed that the villi of the proximal small bowel became short, and that the mucous membrane became atrophied in these four patients. Duodenal biopsies were performed during gastroscopy and the pathological changes of mucosa were confirmed to be Marsh 3 stage of CD. A gluten free diet significantly improved the conditions of the four patients. We suspect that in China, especially in the northern area where wheat is the main food, CD might not be uncommon, and its under-diagnosis could be caused by its clinical manifestations that could be easily covered by the symptoms from other clinical situations, particularly when it came to subclinical patients without obvious symptom or to patients with extraintestinal symptoms as the initial manifestations.  相似文献   
155.
计算机网络的实验教学一直是该门课的教学难点,直观的教学平台很难搭建。OPNET是一款计算机网络仿真软件,目前在网络的性能研究,网络规划方面得到了广泛的应用,将网络仿真工具应用于计算机网络的教学,可以直观地了解网络的分层结构和网络的性能,通过对CSMA/CD协议的建模仿真过程的研究,表明网络软件仿真计算机网络的教学有很好的应用前景。  相似文献   
156.
屈亚文 《科教文汇》2011,(13):203-204
随书光盘成为继图书、期刊资源之外的又一重要的馆藏资源形式。随书光盘的管理和利用急切需要将它规范科学地著录。本文探讨光盘和图书一起著录时,如何能更有效、更简洁地显示光盘的信息,提出对图书数据的相关字段做相应处理的论点,在科学规范著录方面作了探索。  相似文献   
157.
This study aimed to explore the molecular mechanism in tumor invasion and metastasis. The expression of matrix metalloproteinase-2, −9 (MMP-2, MMP-9), tissue inhibitor-1 of matrix metalloproteinase (TIMP-1), cell adhesion molecule 44 variant 6 (CD44v6), HER2/neu and p53 was investigated in 154 patients with head and neck squamous cell carcinoma (SCC) by ABC and ImmunoMax immunohistochemical method. Their clinical relevance and correlation were analysed. The expression of MMP-2, MMP-9, TIMP-1, CD44v6, HER2/neu and p53 was found in cancer cells in 87.01%, 85.71%, 68.18%, 98.05%, 55.19% and 50.65% cases respectively. Linear regression and correlation analysis revealed that there was close positive relationship (P<0.05) between the expression of MMP-2 and MMP-9, TIMP-1 and CD44v6, HER2/neu and MMP-9, MMP-2 and p53. Up-regulation of MMP-2 was accompanied by advanced T stage (P<0.01). There was also a trend of MMP-2 expression being related with tumor metastasis. Increased expression of HER2/neu was found in patients with tumor recurrence (P<0.05). The expression of TIMP-1 was higher in laryngeal cancer than that in pharyngeal cancer, and higher in keratinizing and non-keratinizing SCC than that in basaloid SCC (P<0.05). These findings suggested that MMP-2 and MMP-9, HER2/neu and MMP-9, MMP-2 and p53 had a coordinate function in aggression of tumor; that MMP-2 had a more important function than MMP-9 in tumor invasion and metastasis; and that HER2/neu might serve as a biomarker for poor prognosis in HNSCC. Project supported by Lübeck Medical University, Germany  相似文献   
158.
结合大学化学教学的实际情况,应用CaussView对配合物的旋光异构现象进行了直观的解释,有利于学生形象地理解其空间结构,增强课堂教学的趣味性,激发学生的兴趣.  相似文献   
159.
Probability density function (PDF) method is proposed for analysing the structure of the reconstructed attractor in computing the correlation dimensions of RR intervals of ten normal old men.PDF contains important information about the spatial distribution of the phase points in the reconstructed attractor.To the best of our knowledge, it is the first time that the PDF method is put forward for the analysis of the reconstructed attractor structure.Numerical simulations demonstrate that the cardiac systems of healthy old men are about 6-6.5 dimensional complex dynamical systems.It is found that PDF is not symmetrically distributed when time delay is small, while PDF satisfies Gaussian distribution when time delay is big enough.A cluster effect mechanism is presented to explain this phenomenon.By studying the shape of PDFs, that the roles played by time delay are more important than embedding dimension in the reconstruction is clearly indicated.Results have demonstrated that the PDF method represents a promising numerical approach for the observation of the reconstructed attractor structure and may provide more information and new diagnostic potential of the analyzed cardiac system.  相似文献   
160.
分工与协作的多元化使得供应链成员间的关系呈现出网络化的趋势。为更合理地设计供应链网络,基于投入与产出的视角,利用柯布-道格拉斯函数,分析在资源优化配置条件下供应链资源投入成本与产出数量间的基本关系,在此基础上构建不同市场结构下的供应链网络竞争模型,指出竞争网络规模和供应链个体差异对网络均衡的影响。认为供应链网络规模的增加将导致供应链个体和供应链网络整体利润水平的降低,供应链个体转化能力的差异化却能缓解网络规模增加的不利。通过数值算例分析,验证所得出的结论。  相似文献   
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