一类泛圈图

本文证明了如果G是2连通无爪图,G不是圈,n=|v(G)|>q,G的每个导出子图A都满足φ(a_1,a_2),且G中不存在W′作为其导出子图,则G是泛圈图。     

髓母细胞瘤中P53、bcl-2及Ki-67的表达及其意义

用免疫组化S P法检测 2 5例髓母细胞瘤中Ki 6 7、P53 及bcl 2基因的表达。结果表明 ,在 2 5例髓母细胞瘤中 ,bcl 2和P53 蛋白的阳性表达率分别为 72 % (18/ 2 5 )和 16 % (4/ 2 5 )。Ki 6 7阳性率平均为 (33.34± 4 .98) % ,其表达与组织学分型有关。说明在髓母细胞瘤中bcl 2蛋白与P53 蛋白可能参与调控细胞的凋亡     

平面三自由度并联机构的正解分析

文章分析了一般结构尺度的平面三自由度并联机构的正解。首先,建立了含有移动副的平面三自由度并联机构运动分析的方程,并将其化解为只含有从动件一个运动位置参数的代数方程(一元六次方程),通过优化迭代计算出六个解;其次,介绍了全为转动副的平面三自由度并联机构的解,可在含有移动副机构解的基础上进行分析;最后,给出了一个算例,说明了求解过程的可行性。     

日语中和“木”有关的表达方式

日本是森林大国，因此日语中和树木有关的表达方式极其丰富。本文拟就日语中和树木有关的表达方式做一个总结，强调了日本的“木”文化对日语表迭起到的作用以厦由此形成的特色．旨在将文化学习与语言学习有机地结合起来。     

ki67、Cytokeratin19在口腔粘膜扁平苔藓及口腔鳞癌上皮组织中表达的研究

目的研究口腔粘膜扁平苔藓及口腔鳞癌患者口腔粘膜上皮ki67,Cytokeratin19的表达,探讨012发病的可能机理及是否为癌前病变。方法用免疫组化SABC法检测20例口腔粘膜扁平苔藓患者口腔粘膜组织及30例OSCC13腔粘膜组织中ki67,Cytokeratin19的表达并行细胞计数,其中对Cytokeratin19的表达行半定量统计分析。结果（1）OLP与正常组中ki67中阳性表达率有显著差异,P〈0.05;（2）Cytokeratin19行半定量分析发现OLP组与OSCC组有显著差异,P〈0.05。结论（1）ki67,Cytokeratin19的异常表达可能是OLP,OSCC的发病原因。（2）Cytokertin19、ki67的高表达均提示OLP可能是一种癌前病变。（3）Cytokertin19、ki67可作为口腔鳞癌检测的指标。     

Characterization of the separate kinase domain of chicken liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase

The bifunctional enzvme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase consists of two dis tinct domains which catalyze the synthesis and hydrolysis of fructose-2, 6-bisphosphate, respectively. In this work the properties of the separate 6-phosphofructo-2-kinase domain were investigated. Purification of the expressed separate do main or isolation of this domain from purified glutathione S-transferase (GST) fusion protein with thrombin cleavage led to the loss of its kinase activity. Thus the domain in the GST-tagged form was characterized. The two forms of the do main with different lengths (amino acids 1 ～ 249 and 1 ～ 286) were very similar in kinetic property and could catalyze the formation of fructose-2,6-bisphosphate with a kcat 4-fold lower than that of the full-length enzyme. In addition, the domain was much more sensitive to guanidine inactivation and heat denaturation, and less stable at pH values below 7 than the full-length enzyme. The results suggest that the separate kinase domain of the bifunctional enzyme is far less perfect in structure in the absence of the bisphosphatase domain, though it still possesses the 6-phosphofructo-2-kinase activity.