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301.
302.
Chemotherapy and immunotherapy of malignant glioma: molecular mechanisms and clinical perspectives 总被引:5,自引:0,他引:5
Despite the considerable progress in modern tumor therapy, the prognosis for patients with glioblastoma, the most frequent
malignant brain tumor, has not been substantially improved. Although cytoreductive surgery and radiotherapy are the mainstays
of treatment for malignant glioma at present, novel cytotoxic drugs and immunotherapeutic approaches hold great promise as
effective weapons against these malignancies. Thus, great efforts are being made to enhance antitumoral efficacy by combining
various cytotoxic agents, by novel routes of drug administration, or by combining anticancer drugs and immune modulators.
Immunotherapeutic approaches include cytotoxic cytokines, targeted antibodies, and vaccination strategies. However, the success
of most of these experimental therapies is prevented by the marked molecular resistance of glioma cells to diverse cytotoxic
agents or by glioma-associated immunosuppression. One promising experimental strategy to target glioma is the employment of
death ligands such as CD95 (Fas/Apo1) ligand or Apo2 ligand (TRAIL). Specific proapoptotic approaches may overcome many of
the obvious obstacles to a satisfactory management of malignant brain tumors.
Received 8 March 1999; received after revision 27 May 1999; accepted 14 June 1999 相似文献
303.
新型涡流磁阻尼月球着陆器 总被引:1,自引:0,他引:1
针对三支撑月球着陆器摩擦式阻尼材料存在的真空冷焊问题,对非接触式涡流磁阻尼在月球着陆器上的应用进行了分析和试验.应用电磁学基本理论对涡流磁阻尼的基本特性进行了分析,得出了阻尼特性基本方程.使用DASP数据采集与分析软件,对新型涡流磁阻尼月球着陆器原理模型的缓冲特性进行了试验测试.结果表明,新型涡流磁阻尼月球着陆器具有较好的缓冲效果. 相似文献
304.
IntroductionNettle is a perennial root herd plant of Urticaceaefamily . There are 16 species of Urtica growing in China and6 of them growing in the Northen and Southwesten Chineseprovinces of Xinjiang , Gansu,Sichuan and Shaanxi . Alsointhe Northeast of China nettle abounds as a wild naturalresource . The basts of many Urtica plants stems are rich infibers , which are snowwhite , soft and can be used as atextile materials . The natural harl goods have many specialcharacteristics ,for ins… 相似文献
305.
《须溪词》遗民心态的变异及溯源 总被引:1,自引:0,他引:1
研究刘辰翁及其《须溪词》者众多,然而就刘辰翁志节言,一致认为是位出色的爱国者,对前朝的忠贞始终不渝,直到终老。其实检阅《须溪词》,刘辰翁的遗民心态也非全如此。刘辰翁《须溪词》的遗民思想、隐逸心态也是发展变化的。特别是他后期的某些心态相对全词的主体遗民思想而言,确实又带有变异的色彩。虽然这种现象比较微妙,不容易查考,也不能遮掩词人的总体精神风貌,但无疑也是当时词人的实际情感思想的表现,客观上为我们比较全面真实地研究刘辰翁《须溪词》的遗民心态提供了新的探测点,而这却正是历来评家所忽视的。 相似文献
306.
307.
甘蓝型杂交油菜"蜀杂9号"种子纯度的RAPD鉴定 总被引:4,自引:0,他引:4
通过50个随机引物对“蜀杂9号”亲本进行RAPD扩增,选出了两个能在父、母本间产生多态性扩增的随机引物S18和S31,在杂种F,代中验证了它们的特异性和稳定性,证明随机引物S18和S31能分别在F1代中稳定扩增出父本和母本的特异标记片段S18750与S31550.对该引物的RAPD-PCR的反应体系优化后,对“蜀杂9号”父、母本和杂种F1代的单株进行了随机检测,结果表明这两个RAPD标记配合使用能稳定可靠地鉴定甘蓝型杂交油菜“蜀杂9号”种子的纯度. 相似文献
308.
Expression of lysine-rich protein gene and analysis of lysine content in transgenic wheat 总被引:2,自引:0,他引:2
MENGChaomin CHENXuqing LIANGRongqi YANGFengping ZHANGLiquan ZHANGXiaodong CHENTianyou S.S.M.Sun 《科学通报(英文版)》2004,49(19):2053-2057
Expression vector pBPC102, which carries winged bean lysine-rich protein (wblrp) gene and dihydropicolinate synthase (DHDPS) gene, was transferred into hexaploid winter wheat cv. Jinghua No.l, Jing411, You899 and Yangnongl5 explants of immature inflorescence and immature embryos by particle bombardment. More than 100 transgenic plants were obtained under the selection of s-(2-aminoethyl)-L-cysteine (AEC). Confirmed transgenic plants of To and TI generation by PCR and PCR-Southern blotting analyses showed successful integration of wblrp gene into wheat genome. Analysis of transgenic plant lines of T2 by Northern dot-blotting showed good expression of wblrp gene in offspring seed. The content of free lysine in leaves, contents of bound lysine and total proteins in seeds of T2 transgenie wheat lines were determined and analyzed. Among 34 tested transgenic lines, levels of free lysine content in leaves of 9 transgenic lines are 2~3times higher than un-trans-formed wild-type cultivars. Among 17 analyzed transgenic lines, bound lysine content of 4 transgenic lines is more than 10% higher than that of wild-type cultivars. Our research suggests that introducing wblrp gene into wheat is an effective way to improve its nutrition quality. 相似文献
309.
Malaria results in up to 2.5 million deaths annually, with young children and pregnant women at greatest risk. The great
majority of severe disease is caused by Plasmodium falciparum. A characteristic feature of infection with P. falciparum is the accumulation or sequestration of parasite-infected red blood cells (RBCs) in various organs, such as the brain, lung
and placenta, and together with other factors is important in the pathogenesis of severe forms of malaria. Sequestration results
from adhesive interactions between parasite-derived proteins expressed on the surface of infected RBCs and a number of host
molecules on the surface of endothelial cells, placental cells and uninfected RBCs. Some receptors for parasite adhesion have
been implicated in particular malaria syndromes, such as intercellular adhesion molecule 1 in cerebral malaria and chondroitin
sulfate A and hyaluronic acid in placental infection. The principal parasite ligand and antigen on the RBC surface, P. falciparum erythrocyte membrane protein 1 encoded by a multigene family termed var, is clonally variant, enabling evasion of specific immune responses. An understanding of these host-parasite interactions
in the context of clinical disease and immunity may reveal potential targets to prevent or treat severe forms of malaria.
Received 25 June 2001; received after revision 22 August 2001; accepted 24 August 2001 相似文献
310.
基于我国《建筑结构设计统一标准》的极限状态设计原则,结构物不允许出现影响正常使用的外观变形,提出了刚架结构位移连续变更方法·用数值分析与递推公式相结合的方法,实现连续变更结构的变形极限状态函数的连续生成·重分析不必重新形成结构刚度矩阵,不必反复求逆矩阵,使得识别系统主要失效模式的方法得以简化,有效地提高了计算时效,并为刚度可靠性分析提供了新方法·算例验证了方法的正确性及实用性· 相似文献