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   273篇
  免费   18篇
  2022年   1篇
  2021年   3篇
  2020年   1篇
  2019年   1篇
  2018年   6篇
  2017年   3篇
  2016年   7篇
  2015年   14篇
  2014年   9篇
  2013年   14篇
  2012年   19篇
  2011年   24篇
  2010年   18篇
  2009年   13篇
  2008年   13篇
  2007年   17篇
  2006年   20篇
  2005年   15篇
  2004年   19篇
  2003年   15篇
  2002年   12篇
  2001年   3篇
  2000年   3篇
  1999年   5篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1994年   1篇
  1992年   2篇
  1990年   1篇
  1989年   2篇
  1988年   4篇
  1987年   1篇
  1986年   4篇
  1985年   1篇
  1984年   1篇
  1982年   1篇
  1980年   1篇
  1975年   2篇
  1974年   2篇
  1972年   3篇
  1968年   2篇
  1965年   2篇
  1949年   1篇
  1941年   1篇
排序方式: 共有291条查询结果,搜索用时 15 毫秒
41.
Development of various vaccines for prostate cancer (PCa) is becoming an active research area. PCa vaccines are perceived to have less toxicity compared with the available cytotoxic agents. While various immune-based strategies can elicit anti-tumour responses, DNA vaccines present increased efficacy, inducing both humoural and cellular immunity. This immune activation has been proven effective in animal models and initial clinical trials are encouraging. However, to validate the role of DNA vaccination in currently available PCa management paradigms, strong clinical evidence is still lacking. This article provides an overview of the basic principles of DNA vaccines and aims to provide a summary of preclinical and clinical trials outlining the benefits of this immunotherapy in the management of PCa.  相似文献   
42.
43.
The role of nitric oxide (NO) produced by adherent spleen cells in the systemic immunosuppression developing in tumor-bearing hosts was investigated. After therapeutic immunization of rats carrying an intrahepatic colon carcinoma, H1D2, the spleen cell antitumor immune responsiveness was analyzed. Compared to parallel immunized tumor-free rats, tumor-bearing rats (TB rats) had a greatly reduced proliferative T-cell response to wild-type tumor stimulator cells. The TB rats had a depressed proliferative response to anti-CD3 and to the superantigen SEA. TB rats with small tumors had a stronger response to IL-18-producing H1D2 stimulator cells than to wild type H1D2 cells. This was not the case with TB rats carrying larger tumors. Also the IFN-gamma production and cytotoxicity against the wild-type tumor cells and the NK sensitive YAC cells were depressed in spleen cells of TB rats after 5-day restimulation with wild-type tumor cells. A part of this immunosuppression was mediated by adherent spleen cells, mostly consisting of macrophages. An important mode of action appears to involve their production of an enhanced level of nitric oxide, since the competitive nitric oxide synthase (NOS) inhibitor L-NAME could partially counteract the suppression in vitro. We conclude that NOS inhibitors in combination with immunostimulatory cytokines, such as IL-18, could be useful tools to enhance anti-tumor immune responses in TB rats and therefore to increase the efficiency of immunotherapies.  相似文献   
44.
45.
Modern therapy cures 80% of all children with brains tumors, but may also cause long-lasting side effects, so called late effects. Radiotherapy is particularly prone to cause severe late effects, such as intellectual impairment. The extent and nature of the resulting cognitive deficits may be influenced by age, treatment and gender, where girls suffer more severe late effects than boys. The reason for this difference between boys and girls is unknown, but very few experimental studies have addressed this issue. Our aim was to investigate the effects of ionizing radiation on the corpus callosum (CC) in both male and female mice. We found that a single dose of 8 Gray (Gy) to the brains of postnatal day 14 mice induced apoptosis in the CC and reduced the number of proliferating cells by one third, as judged by the number of phospho-histone H3 positive cells 6 h after irradiation (IR). BrdU incorporation was reduced (62% and 42% lower in females and males, respectively) and the number of oligodendrocytes (Olig2+ cells) was lower (43% and 21% fewer in females and males, respectively) 4 months after IR, so the lack of developing and differentiated cells was more pronounced in females. The number of microglia was unchanged in females but increased in males at this late time point. The density of microvessel profiles was unchanged by IR. This single, moderate dose of 8 Gy impaired the brain growth to some extent (8.1% and 0.4% lower brain/body weight ratio in females and males, respectively) but the CC growth was even more impaired (31% and 19% smaller in females and males, respectively) 4 months after IR compared with non-irradiated mice. In conclusion, this is the first study to our knowledge demonstrating that IR to the young rodent brain affects white matter development more in females than in males.  相似文献   
46.
Rod outer segment membrane is analyzed using the spin resonance label technique by means of two probes. The solubility of the first label,2,2,6,6-tetramethylpiperidin-1-oxyl, is correlated with the membrane fluidity which is measured using a stearic acid spin probe. The two values are compared to the solubility-fluidity relationship which characterizes a model system in which all lipids are in a fluid state. The analysis leads to the conclusion that only two thirds of the membrane lipids are fluid. This conclusion is reinforced by the observation that partial lipid removal leaves rigid lipids associated with the rhodopsin molecules.  相似文献   
47.

Background  

There is a growing awareness of the importance of intracellular events in determining the outcome of infectious disease. To improve the understanding of such events, like phagosome maturation, we set out to develop a versatile technique for phagosome isolation that is rapid and widely applicable to different pathogens.  相似文献   
48.
49.
Populations of metazoan microfauna (nematodes, rotifers and tardigrades) are patchily distributed on mountain outcrops penetrating the ice sheet (nunataks) in continental Antarctica. The abundance and fauna composition of microscopic animals vary greatly also among samples from similar types of habitats. Occurrence of similar seemingly habitable sites without microfauna and sites with various combinations of animal taxa indicates that stochastic colonization processes as well as local environmental factors and historical factors influence faunal composition in a specific habitable patch. The abundance of nematodes, rotifers and tardigrades in various combinations of co-occurrence was analyzed. One objective was to investigate if biotic interactions structuring these simple communities could be observed. The 368 samples analysed originate from three kinds of habitats, viz. mosses, ornithogenic soils and fellfield soils, obtained from 14 nunataks in Dronning Maud Land, East Antarctica. It is suggested that high population densities of any of the three animal groups, when they were found alone and lower densities, when they coexisted with other taxa could indicate the presence of competition or predation. However, the great variability in microfauna densities for similar habitable patches made it difficult to find significant differences among population densities in samples with varying complexity.  相似文献   
50.
We have previously identified a new gene with sequence homology to the WASP-family of actin regulators denoted WAFL (WASP and FKBP-like). Here we report a possible biological function for WAFL, by demonstrating an association to early endosomes via its central coiled-coil domain. Further we show by functional and structural studies that WAFL is associated with both microtubules and the actin filament system, the two means of transport of early endosomes. In addition, WAFL interacts with WASP-interacting protein (WIP) and actin, thus linking WAFL to actin dynamics. The use of RNAi depletion of WAFL shows that WAFL-deficient cells display delayed transport of endosomal cargo. Our findings are compatible with a model whereby WAFL is involved in the transport of early endosomes at the level of transition between microfilament-based and microtubule-based movement.  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