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   164篇
  免费   4篇
  国内免费   1篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   2篇
  2018年   2篇
  2017年   1篇
  2016年   2篇
  2015年   1篇
  2014年   7篇
  2013年   12篇
  2012年   10篇
  2011年   4篇
  2010年   4篇
  2009年   7篇
  2008年   9篇
  2007年   3篇
  2006年   4篇
  2005年   6篇
  2004年   7篇
  2003年   3篇
  2002年   2篇
  2001年   1篇
  2000年   1篇
  1999年   10篇
  1998年   4篇
  1997年   3篇
  1995年   3篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   1篇
  1989年   2篇
  1988年   2篇
  1987年   3篇
  1986年   3篇
  1985年   5篇
  1983年   2篇
  1982年   3篇
  1980年   7篇
  1979年   2篇
  1978年   2篇
  1976年   3篇
  1975年   1篇
  1974年   1篇
  1973年   3篇
  1971年   2篇
  1959年   1篇
  1951年   1篇
  1950年   1篇
  1930年   1篇
排序方式: 共有169条查询结果,搜索用时 15 毫秒
91.
Pulmonary intravascular macrophages (PIMs) are present in ruminants and horses. These species are highly sensitive to acute lung inflammation compared with non-PIM-containing species such as rats and humans. There is evidence that rats and humans may also recruit PIMs under certain conditions. We investigated precise contributions of PIMs to acute lung inflammation in a calf model. First, PIMs were recognized with a combination of in vivo phagocytic tracer Monastral blue and postembedding immunohistology with anti-CD68 monoclonal antibody. Second, gadolinium chloride depleted PIMs within 48 h of treatment (P < 0.05). Finally, PIMs contain TNF-alpha, and their depletion reduces cells positive for IL-8 (P < 0.05) and TNF-alpha (P < 0.05) and histopathological signs of acute lung inflammation in calves infected with Mannheimia hemolytica. The majority of IL-8-positive inflammatory cells in lung septa of infected calves were platelets. Platelets from normal cattle contained preformed IL-8 that was released upon in vitro exposure to thrombin (P < 0.05). These novel data show that PIMs, as the source of TNF-alpha, promote recruitment of inflammatory cells including IL-8-containing platelets to stimulate acute inflammation and pathology in lungs. These data may also be relevant to humans due to our ability to recruit PIMs.  相似文献   
92.
Neurochemical Research - Neuroinflammation is characterized by reactive microglia and astrocytes (collectively called gliosis) in the central nervous system and is considered as one of the main...  相似文献   
93.
Sulfonation is an important conjugation reaction required for a range of biological processes including phase II metabolism, whereby sulfo-conjugation renders a compound more hydrophilic to aid its excretion. The major enzyme responsible for xenobiotic sulfonation is the widely expressed cytosolic sulfotransferase SULT1A1. The SULT1A1 crystal structure has provided insights into this enzyme's substrate specificity and catalytic function, including its role in the sulfonation of endogenous substrates such as oestrogens. Contrary to its metabolic role, SULT1A1 can also bioactivate compounds; it is known to sulfonate pro-carcinogens such as hydroxymethyl polycyclic aromatic hydrocarbons leading to highly reactive intermediates capable of forming DNA adducts, potentially resulting in mutagenesis. Given the role of SULT1A1 in these diverse functions and the discovery of allelic variants with differing catalytic activities, this enzyme has been the focus of numerous polymorphic studies investigating the link between inter-individual SULT1A1 variance and the etiology of a variety of cancers.  相似文献   
94.
95.
Identification of disease-causing genes among a large number of candidates is a fundamental challenge in human disease studies. However, it is still time-consuming and laborious to determine the real disease-causing genes by biological experiments. With the advances of the high-throughput techniques, a large number of protein-protein interactions have been produced. Therefore, to address this issue, several methods based on protein interaction network have been proposed. In this paper, we propose a shortest path-based algorithm, named SPranker, to prioritize disease-causing genes in protein interaction networks. Considering the fact that diseases with similar phenotypes are generally caused by functionally related genes, we further propose an improved algorithm SPGOranker by integrating the semantic similarity of GO annotations. SPGOranker not only considers the topological similarity between protein pairs in a protein interaction network but also takes their functional similarity into account. The proposed algorithms SPranker and SPGOranker were applied to 1598 known orphan disease-causing genes from 172 orphan diseases and compared with three state-of-the-art approaches, ICN, VS and RWR. The experimental results show that SPranker and SPGOranker outperform ICN, VS, and RWR for the prioritization of orphan disease-causing genes. Importantly, for the case study of severe combined immunodeficiency, SPranker and SPGOranker predict several novel causal genes.  相似文献   
96.
97.

Background  

Automated microscopy technologies have led to a rapid growth in imaging data on a scale comparable to that of the genomic revolution. High throughput screens are now being performed to determine the localisation of all of proteins in a proteome. Closer to the bench, large image sets of proteins in treated and untreated cells are being captured on a daily basis to determine function and interactions. Hence there is a need for new methodologies and protocols to test for difference in subcellular imaging both to remove bias and enable throughput. Here we introduce a novel method of statistical testing, and supporting software, to give a rigorous test for difference in imaging. We also outline the key questions and steps in establishing an analysis pipeline.  相似文献   
98.
Natural selection can favor songbirds that desert nests containingeggs of the parasitic brown-headed cowbird (Molothrus ater).However, the high variability in desertion of parasitized nestswithin species is perplexing in light of the typically highcosts of parasitism. Because nest desertion can also be a responseto partial clutch predation, we first asked if Bell's vireos(Vireo bellii) deserted nests in response to the presence ofcowbird eggs (antiparasite response hypothesis) or to egg removalby predators and female cowbirds (egg predation hypothesis).Second, we asked whether variation in nest desertion was dueto intrinsic differences among individuals or to variation innest contents. We monitored a large number of nests (n = 494)and performed a clutch manipulation experiment to test thesehypotheses. The number of vireo eggs that remained in a nestwas a strong predictor of desertion both within and among pairs.Neither the presence of a single cowbird egg, which leads tonest failure for this host, nor the number of cowbird eggs receivedin a vireo nest influenced nest desertion. Furthermore, vireosdid not desert experimental nests when we immediately exchangedcowbird eggs for vireo eggs but deserted if we removed vireoeggs and replaced them with cowbird eggs the following morning.Desertion of parasitized nests by Bell's vireos can be almostentirely explained as a response to partial or complete clutchloss and does not appear to have been altered by selection frombrood parasitism.  相似文献   
99.
A series of phenazine-1-carboxamides were prepared, including variations in both chromophore substituents and the nature of the cationic side chain. The novel side-chain analogues were prepared from the corresponding phenazine-1-carboxylic acids via Schmidt conversion to the 1-amines and from the corresponding 1-halides. Structure-cytotoxicity relationships for these compounds in a panel of tumor cell lines showed that there is very limited scope for variation of the structure of the 1-carboxamide side chain, consistent with the recent structural model of how tricyclic carboxamides bind to DNA. There was generally little difference in IC(50)s between parent and P-glycoprotein expressing cell lines, suggesting that most of the compounds are not affected by the presence of this efflux pump.  相似文献   
100.
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