首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   36篇
  免费   0篇
现状及发展   12篇
研究方法   5篇
综合类   19篇
  2017年   1篇
  2013年   4篇
  2012年   2篇
  2011年   1篇
  2008年   1篇
  2006年   2篇
  2005年   1篇
  2004年   2篇
  2003年   3篇
  2002年   4篇
  2000年   1篇
  1997年   1篇
  1996年   3篇
  1984年   1篇
  1977年   2篇
  1974年   2篇
  1973年   1篇
  1970年   3篇
  1967年   1篇
排序方式: 共有36条查询结果,搜索用时 15 毫秒
11.
2,6-Bis (diphenylphosphinomethyl) pyridine (PNP) reaction with Na2OsCl6 · 6H2O to give the five coordinated, sixteen-electron complex Os (PNP)Cl2. In the presence of formaldehyde, the reaction between Na2OsCl6· 6H2O and PNP proceeds rapidly in boiling ethanol to give the coordinately saturated Os(PNP)Cl2(CO). The IR spectrum of Os(PNP)Cl2(CO) shows a strong absorption band at 1 970 cm−1 assignable tov stretch. PNP reacts with RuCl2(PPh3)3 and RuCl2(DMSO)4 (DMSO=dimethyl sulfoxide) to give Ru(PNP)Cl2 (PPh3) and Ru(PNP)Cl2 (DMSO) respectively. The average Ru−Cl, Ru−P and Ru−N bond distance in Ru(PNP)Cl2(PPh3) determineby X-ray crystallography are 0.242, 0.236 and 0.216 nm, respectively. Li Zhaoying: born in July 1949, associate professor  相似文献   
12.
The recent advances in surgery and radiation therapy have significantly improved the prognosis of patients with primary cancer, and the major challenge of cancer treatment now is metastatic disease development. The 5-year survival rate of cancer patients who have distant metastasis at diagnosis is extremely low, suggesting that prediction and early detection of metastasis would definitely improve their prognosis because suitable patient therapeutic management and treatment strategy can be provided. Cancer cells from a primary site give rise to a metastatic tumor via a number of steps which require the involvement and altered expression of many regulators. These regulators may serve as biomarkers for predicting metastasis. Over the past few years, numerous regulators have been found correlating with metastasis. In this review, we summarize the findings of a number of potential biomarkers that are involved in cadherin–catenin interaction, integrin signaling, PI3K/Akt/mTOR signaling and cancer stem cell identification in gastrointestinal cancers. We will also discuss how certain biomarkers are associated with the tumor microenvironment that favors cancer metastasis.  相似文献   
13.
14.
In 1914, the physics discipline had reached a very similar stage of development in Australia and Japan. A generation later the paths of development had considerably diverged. A systematic comparison of the evolution of physics in the two countries during these years identifies factors—political, economic and cultural—that led to this divergence, but it also uncovers a number of underlying parallels.  相似文献   
15.
好氧颗粒污泥是一种全新概念的污水生物处理技术。介绍了好氧颗粒污泥技术的理论基础,包括好氧污泥形成机理及理化特性研究,探讨了影响好氧颗粒污泥形成的因素以及工业应用的方向和前景。  相似文献   
16.
Summary 2 populations of cells were found in the Deiters' nucleus responsive to direct electrical stimulation of the ipsilateral saccule. Only those Deiters' neurons activated monosynaptically from the saccule could be driven antidromically from the oculomotor nucleus. Such an intracellular study provides strong evidence for a tri-neuronal arc in the sacculo-ocular reflex for vertical eye movements.Acknowledgment. This study was supported by the Medical Faculty Research Grant No. 377/004/03, University of Hong Kong.  相似文献   
17.
'Fimbriae' in the fungus Ustilago violacea   总被引:2,自引:0,他引:2  
H Poon  A W Day 《Nature》1974,250(5468):648-649
  相似文献   
18.
Lu BC  Yu P  Poon DP 《Nature》1970,225(5238):1128-1129
  相似文献   
19.
20.
Immune control of HIV-1 after early treatment of acute infection   总被引:66,自引:0,他引:66  
Virus-specific T-helper cells are considered critical for the control of chronic viral infections. Successful treatment of acute HIV-1 infection leads to augmentation of these responses, but whether this enhances immune control has not been determined. We administered one or two supervised treatment interruptions to eight subjects with treated acute infection, with the plan to restart therapy if viral load exceeded 5,000 copies of HIV-1 RNA per millilitre of plasma (the level at which therapy has been typically recommended) for three consecutive weeks, or 50,000 RNA copies per ml at one time. Here we show that, despite rebound in viraemia, all subjects were able to achieve at least a transient steady state off therapy with viral load below 5,000 RNA copies per ml. At present, five out of eight subjects remain off therapy with viral loads of less than 500 RNA copies per ml plasma after a median 6.5 months (range 5-8.7 months). We observed increased virus-specific cytotoxic T lymphocytes and maintained T-helper-cell responses in all. Our data indicate that functional immune responses can be augmented in a chronic viral infection, and provide rationale for immunotherapy in HIV-1 infection.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号