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71.
从MIS系统的最新发展趋势出发,介绍了用ASP开发的B/S模式MIS系统的结构和性能。在此基础上,通过举例讲解几种具体的MIS信息安全隐患,就用ASP开发的B/S模式MIS系统的信息安全问题进行了简单分析和评价,并分别提供其原因及解决方法。最后总结出:用ASP开发的B/s模式MIS系统的信息安全问题的根源有两个:一是技术漏洞问题.另一是信息人的信息意识问题(最根本原因),并初步探讨了其对策。  相似文献   
72.
对四川省跳水队方敏、侯媛媛、陈莉、祝智佳4名国家级运动员完成三米板405B动作的运动学特征进行了研究,发现了川队运动员与伏明霞的技术差距,并提出了改进意见。  相似文献   
73.
The oxidative modification of lipoprotein especially low density lipoprotein (LDL) plays a key role in the initiation and progression of atherosclerosis. Serum apolipoproteinB (apoB) level is found to be an important marker for atherosclerosis. The present paper focuses on the measurement of serum apoB levels and the effect of Vitamin E, Vitamin C and reduced glutathione on the copper ion induced oxidation of LDL + VLDL (VLDL-Very Low Density Lipoprotein) lipoprotein fraction isolated from the serum of chronic renal failure (CRF) and renal transplanted patients. The level of apoB is significantly higher in the serum of transplanted patients when compared to CRF patients and normal subjects. The level of TBARS formed in oxidized LDL + VLDL lipoprotein fraction of CRF and renal transplanted patients are significantly increased than normal even in the presence of antioxidants but the level of TBARS produced, with antioxidants is comparatively lesser than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded that oxidation of LDL can be prevented at an earlier stage by Vitamin E supplementation. The supplementation with Glutathione serves as the best method of preventing the lipoprotein oxidation among the renal diseased patients.  相似文献   
74.
75.
从B2B的现状入手,指出中国非常需要B2B;从B2B企业的内部环境对B2B出现的问题加以分析,并提出了相关对策,最后对B2B给予了展望。  相似文献   
76.
E-commerce is growing rapidly in Brazil, led by information-intensive and transaction-intensive sectors such as finance, manufacturing, and retail/wholesale. However, Brazil's highly uneven income distribution is a major barrier for B2C diffusion. Government policies have emphasized promotional or enabling initiatives such as e-procurement, tax filings, and providing Internet access to social institutions. E-commerce legislation is just now being developed, and decisions on taxation are being negotiated in the context of international agreements. E-commerce raises issues for Brazil in terms of its relationship to the global economy. Although most online purchases involve imported goods, e-commerce also offers opportunities to participate in international value chains.  相似文献   
77.
梁一子  王自力  司崇占 《现代情报》2005,25(12):219-221
随着Internet的发展,传统的基于EDI的电子商务由于其成本过高,很大程度上限制了其应用范围,已经显露出越来越多的弊端。XML的出现.完全克服了EDI的缺点,再加上Java与XML的完美结合,极大地促进了电子商务尤其是B2B电子商务的发展。本文就如何利用Java与XML技术在基于XML的B2B电子商务的应用系统做了一些研究对应用系统中的关键技术作了阐述。  相似文献   
78.
Indian ethnicity by itself is a strong risk factor for development of CAD in Indian postmenopausal women due to lower HDL levels as compared to Whites and women of oriental origin. We evaluated and compared the short-term effects of menopause, estrogen replacement therapy and combined estrogen and progestin replacement therapy on various atherogenic indices. 40 postmenopausal women, both surgical and natural (20 each) were selected. 10 surgical postmenopausal women were given 0.625 mg conjugated estrogens daily for 6 months and 10 natural postmenopausal women were given 0.625 mg conjugated estrogen with 2.5 mg medroxyprogesterone acetate daily. 20 women were included in the control group and given placebo. Fasting venous blood samples were analyzed for extended lipid profile and calculated atherogenic indices before starting the therapy and after 1,3 and 6 months. LDL and Apolipoprotein B increased (p<0.05) and those of Apolipoprotein A1 and HDL decreased in the control groups. In both the study groups levels of serum cholesterol and LDL decreased (p<0.05) and those of HDL and Apolipoprotein A1 increased (p<0.01). LDL/HDL, Apo B/ApoA1, Total Cholesterol/HDL decreased significantly (p<0.05) in both the study groups compared to the control groups. The effect of estrogen alone was more significant as compared to combination therapy. Log Triglycerides (TG)/HDL ratio showed a decrease in women on estrogen alone but the difference was not significant. Our study confirms that short term HRT has a favorable effect on atherogenic indices in Indian postmenopausal women.  相似文献   
79.
目的 构建能在水稻胚乳中特异表达的幽门螺杆菌细胞毒素相关蛋白(CagA)和霍乱毒素B亚单位(CTB)的植物表达载体.方法 采用高保真PCR技术分别从质粒pGEM CTB和幽门螺杆菌基因组DNA中扩增出CTB和cagA基因,然后用PCR方法直接融合CTB基因和cagA基因.又用PCR法改造了水稻Wx启动子,在其3′端融合加入Ω序列和Kozak序列.通过一系列亚克隆最终将两个融合基因和NOS终止子插入根癌农杆菌双元载体pCAMBI A1300的表达框架内.结果 PCR验证和测序分析证明,CTB和cagA融合基因以正确的方向插入到载体pCAMBI A1300中,并位于水稻Wx启动子后.结论 成功构建CTB和cagA融合基因的植物表达载体,为幽门螺杆菌口服疫苗的研究奠定基础.  相似文献   
80.
对中国兰科植物新种云南巾唇兰Pennilabium yunnanense S.C.Chen&Y.B.Luo作了 描述和绘图。该新种与P.acuminatum(Ridley)Holttum较为接近,区别点在于具较小的花朵 ,直径仅3cm;花瓣白色且上面有深紫色斑点,以及唇瓣侧裂片顶端有流苏。  相似文献   
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