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881.
Liu Y Chen L Peng SY Chen ZX Hoang-Vu C 《Journal of Zhejiang University. Science. B》2005,6(9):913-918
Objectives: To explore the mechanism of development and aggressiveness in gastric carcinomas by investigating the expression and role of CD97 and its cellular ligand CD55 in gastric carcinomas. Methods: Tumor and corresponding normal mucosal tissue, collected from 39 gastric carcinoma patients, were examined by immunohistochemistry and RT-PCR for the expression of CD97 and CD55. Results: CD97stalk was strongly stained on scattered tumor cells or small tumor cell clusters at the invasion front of gastric carcinomas. The expression of CD97stalk was frequently observed in tumors of stage Ⅰ and T1 gastric carcinoma patients. The expression of CD97stalk between Stage Ⅰ and Stage Ⅱ, Ⅲ, Ⅳ specimens showed significant difference (P<0.05), between T1 and T2, T3, T4 specimens also showed significant difference (P<0.05). Specimens with tumor invasion depth limited in mucosa of T 1 specimens showed higher positive CD55 expression than specimens with the same tumor invasion depth in T2, T3, T4 specimens, the expression of CD55 between T1 and T2, T3, T4 specimens was significantly different (P<0.05).There was strong correlation between the distribution patterns of CD97stalk and CD55 on tumor tissues (r=0.73, P<0.05). Signet ring cell carcinomas frequently contained strong CD97stalk and CD55-staining. Conclusions: Our results suggest that CD97stalk is probably involved in the growth, invasion and aggressiveness of gastric carcinomas by binding its cellular ligand CD55. CD97stalk and CD55 could be useful as molecular markers for prognosis and therapy of gastric carcinoma patients. 相似文献
882.
Gillian Morrow Nigel Malin 《Early Years: An International Journal of Research and Development》2004,24(2):163-177
Parental involvement and participation, partnership with parents, and community‐focused development are important features of government initiatives such as the Sure Start project for children under four years of age and their families. A common feature of the rhetoric is ‘empowerment’ as a means of achieving this. This article describes the activity and development of the Parents Committee in one Sure Start programme and uses this to tease out different dimensions of empowerment. In particular, it highlights issues regarding developing empowerment and the dynamic tension between the growth of personal power and the changing symmetry of power relationships. A tentative model of the trajectory of developing empowerment is presented. This may raise challenges for professionals seeking to fulfill their professional role in a complex context and questions as to whether, or how, it might be possible to better prepare professionals for this dimension of their work. 相似文献
883.
884.
Thus far, it is unclear how students can learn most effectively from their own errors. In this study, reflections on the rationale behind self-made errors are assumed to enhance knowledge acquisition. In a field experiment with pre/post/follow-up design, the authors practiced fractions with 174 seventh- and eighth-grade students who were randomly assigned to one of two conditions: The students reflected on either the rationale behind their own errors or on the correct solution corresponding to their own errors. Students in the first condition group demonstrated a greater procedural knowledge at the posttest and at the follow-up test. Furthermore, at the follow-up test, these students demonstrated a higher conceptual knowledge. The implications for theory and school instruction are discussed. 相似文献
885.
为了研究温度场中非线性地基上矩形薄板受简谐激励的1/3次亚谐共振问题,应用弹性力学理论建立其动力学方程,应用Galerkin方法将其转化为非线性振动方程。利用非线性振动的多尺度分析方法求得系统1/3次亚谐共振的近似解,并进行数值计算。分析温度、地基系数、阻尼、几何参数、激励等对系统3次超谐共振的影响。得到了随参数变化响应曲线的变化规律。 相似文献
886.
周建萍 《湖州职业技术学院学报》2006,4(2):56-59
信用证是我国主要的国际贸易结算方式,但在实际操作过程中,出口企业和相关银行却面临种种风险。其中商业、融资、电子商务等环境下的风险可通过出口信用保险来化解。出口信用保险以其特有的作用给出口企业和银行在收汇过程中增加了一道安全网。发展和完善出口信用保险,有利于提高出口企业的国际竞争力,促进我国对外贸易的发展。 相似文献
887.
通过对《中国翻译》、《外国语》、《外语教学与研究》等著名学术期刊上的学术论文标题汉英翻译的研究 ,从汉语学术论文标题的语言表达形式、汉语学术论文标题的语法结构形式、主副标题结构形式等三个方面 ,归纳出一些常用的汉语学术论文标题翻译技巧和处理方法 ,以探求论文标题翻译之道。 相似文献
888.
P2P技术是目前计算机钟研究的热点问题,在文件交换、对等计算、协同工作、即时通讯、搜索引擎等诸多方面得到了广泛的应用和研究。叙述了P2P的基本概念、技术特性,分析了P2P模型与C/S模型的区别,讨论了P2P技术平台和主要应用,最后展望了P2P技术的发展前景。 相似文献
889.
野生食用蔬菜——臭菜风味成分分析 总被引:1,自引:0,他引:1
刘锡葵 《昆明师范高等专科学校学报》2006,28(4):5-7
采用水蒸气蒸馏的方法对云南特色野生食用木本蔬菜资源——臭菜(Acacia pennata)的香味成分进行了提取,并运用GC/MS技术对臭菜挥发油成分和组成进行了分析鉴定,从臭菜挥发油中分离鉴定33个化合物.臭菜挥发油含有大量的含硫化物,含量占挥发油总量的96.80%,主要成分噻啶thialdine含量高达79.51%,是臭菜的特征风味成分,与一般的野生蔬菜香味成分明显不同. 相似文献
890.
气相色谱-质谱联用法分析奶及乳制品中的脂肪酸 总被引:1,自引:1,他引:1
对奶及乳制品中脂肪酸的组成和含量进行测定.采用哥特里-罗兹法提取奶及乳制品中的脂肪油,氢氧化钾-甲醇溶液法甲酯化,以气相色谱-质谱联用仪进行了分析,结果表明奶及乳制品中的脂肪酸主要以碳8到碳24的脂肪酸为主,各脂肪酸在不同类型的奶及乳制品中含量也不相同. 相似文献