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   161篇
  免费   8篇
  国内免费   1篇
  2023年   1篇
  2021年   2篇
  2020年   2篇
  2019年   1篇
  2018年   5篇
  2017年   1篇
  2016年   1篇
  2015年   7篇
  2014年   7篇
  2013年   11篇
  2012年   14篇
  2011年   7篇
  2010年   11篇
  2009年   12篇
  2008年   4篇
  2007年   9篇
  2006年   6篇
  2005年   4篇
  2004年   14篇
  2003年   6篇
  2002年   2篇
  2001年   5篇
  2000年   5篇
  1999年   2篇
  1998年   9篇
  1997年   3篇
  1996年   3篇
  1994年   3篇
  1993年   1篇
  1991年   1篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1983年   3篇
  1982年   1篇
  1975年   1篇
排序方式: 共有170条查询结果,搜索用时 171 毫秒
111.
The aim of this study was to explore the effectiveness of different parts of J. curcas plant against some selected human pathogens as antimicrobial agent which are known to cause diseases and to check antioxidant and phytochemicals from different plant sections of J. curcas. Plant extracts were analyzed by quantification of antimicrobial and phytochemical compounds. This study reveals that 20% ethanol stem extract of J. curcas showed maximum antibacterial activity (40 ± 0.0 mm) against Klebsiella pneumonia. Water extract of root of J. curcas also inhibited E. coli (35.25 ± 0.35 mm). The growth of K. pneumonia and Agrobacterium tumifaciens were also ceased when ethanol extract of J. curcas root applied to check their potential as antimicrobial agent. The results also revealed that fungal species, Aspergillus niger, and Pencillium notatum noted the maximum antifungal activity in ethanol extract of flower and methanol extract of root (38.5 ± 0.7 mm) and (27.25 ± 0.35 mm) respectively. Phytochemicals and many secondary metabolites were present in J. curcas extracts such as alkaloids, steroids, tannins, glycosides, flavonoids, saponins, courmerin, and phenolic compounds. It also showed the highest density of color in the different parts of plant extract of J. curcas. Similarly, biochemical primary metabolites were observed at maximum amount of biochemical in different parts of J. curcas, and correlated with antimicrobial activity. The study concluded that J. curcas has great potential as antibacterial agent and cure various human pathogens.  相似文献   
112.
113.
Adult plant resistance (APR) to stripe rust in three European (Pegaso, Victo and Aztec) and four New Zealand cultivars (Weka, Kopara, Kokart and Takahe) was characterised using hybrid analysis and tests of allelism. In agreement with earlier work, the APR in most of these cultivars appeared to be controlled by two or more genes with additive effects. It was suggested that heavy selection pressure should be avoided in early generations in breeding programs utilising APR, because lines in which APR genes are heterozygous may display lower levels of resistance due to the incompletely dominant and interactive nature of many APRs. Such lines are capable of generating more resistant progenies following selfing. It was also demonstrated that it is possible to misclassify F2 plants as susceptible if APR genes are in a heterozygous condition, especially in the case of gene(s) conferring intermediate levels of resistance. The presence of a common APR gene in Kopara and Takahe, and perhaps Weka, was suggested because all shared a common parent in their pedigree and no susceptible plants were observed in F2 populations derived from intercrossing them. The difficulties inherent in conducting genetic studies on APRs and the need for large population sizes for such studies were emphasised.  相似文献   
114.
115.
Herein we describe a new rhynchocephalian taxon from the Middle Jurassic of Patagonia, Argentina, representing the first Jurassic record of the group in South America. The new taxon, consisting of a complete dentary, is ascribed to Sphenodontia based on the presence of a deep and wide Meckelian groove, long posterior process, well‐developed coronoid process, and acrodont teeth showing dental regionalization including successional, alternate hatchling, and additional series. This allocation is reinforced by a phylogenetic analysis that places the new taxon in a basal position within a clade of sphenodontians that excludes Diphydontosaurus and Planocephalosaurus. Additionally, the new taxon clusters within a Gondwanan clade with the Indian Godavarisaurus from the Jurassic Kota Formation, sharing the presence of recurved and relatively large posterior successional teeth that are ribbed and bear a peculiar anterolingual groove. This sister‐group relationship is intriguing from a palaeobiogeographical viewpoint, as it suggests some degree of endemism during the initial stages of the breakup of Pangaea. We also discuss the ontogenetic stage of the new taxon and provide insights on the evolution of successional dentition in rhynchocephalians. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 342–360.  相似文献   
116.
Since the early 2000s, the Aurora kinases have become major targets of oncology drug discovery particularly Aurora-A and Aurora-B kinases (AKA/AKB) for which the selective inhibition in cells lead to different phenotypes. In addition to targeting these Aurora kinases involved in mitosis, CDK1 has been added as a primary inhibition target in hopes of enhancing the cytotoxicity of our chemotypes harboring the pyrazolopyrimidine core. SAR optimization of this series using the AKA, AKB and CDK1 biochemical assays led to the discovery of the compound 7h which combines strong potency against the 3 kinases with an acceptable microsomal stability. Finally, switching from a primary amide to a two-substituted pyrrolidine amide gave rise to compound 15a which exhibited the desired AKA/CDK1 inhibition phenotype in cells but showed moderate activity in animal models using HCT116 tumor cell lines.  相似文献   
117.
118.

Objectives

To investigate the safety and immunogenicity of a booster BCG vaccination delivered intradermally in healthy, BCG vaccinated subjects and to compare with a previous clinical trial where BCG vaccinated subjects were boosted with a new TB vaccine, MVA85A.

Design

Phase I open label observational trial, in the UK. Healthy, HIV-negative, BCG vaccinated adults were recruited and vaccinated with BCG. The primary outcome was safety; the secondary outcome was cellular immune responses to antigen 85, overlapping peptides of antigen 85A and tuberculin purified protein derivative (PPD) detected by ex vivo interferon-gamma (IFN-γ) ELISpot assay and flow cytometry.

Results and Conclusions

BCG revaccination (BCG-BCG) was well tolerated, and boosting of pre-existing PPD-specific T cell responses was observed. However, when these results were compared with data from a previous clinical trial, where BCG was boosted with MVA85A (BCG-MVA85A), MVA85A induced significantly higher levels (>2-fold) of antigen 85-specific CD4+ T cells (both antigen and peptide pool responses) than boosting with BCG, up to 52 weeks post-vaccination (p = 0.009). To identify antigen 85A-specific CD8+ T cells that were not detectable by ex vivo ELISpot and flow cytometry, dendritic cells (DC) were used to amplify CD8+ T cells from PBMC samples. We observed low, but detectable levels of antigen 85A-specific CD8+ T cells producing IFNγ (1.5% of total CD8 population) in the BCG primed subjects after BCG boosting in 1 (20%) of 5 subjects. In contrast, in BCG-MVA85A vaccinated subjects, high levels of antigen 85A-specific CD8+ T cells (up to 14% total CD8 population) were observed after boosting with MVA85A, in 4 (50%) of 8 subjects evaluated.In conclusion, revaccination with BCG resulted in modest boosting of pre-existing immune responses to PPD and antigen 85, but vaccination with BCG-MVA85A induced a significantly higher response to antigen 85 and generated a higher frequency of antigen 85A-specific CD8+ T cells.

Trial Registration

ClinicalTrials.gov NCT00654316 NCT00427830  相似文献   
119.

Background  

Ran GTPase has multiple functions during the cell division cycle, including nucleocytoplasmic transport, mitotic spindle assembly and nuclear envelope formation. The activity of Ran is determined by both its guanine nucleotide-bound state and its subcellular localization.  相似文献   
120.

Background  

Many researchers have reported on the optimization of protease production; nevertheless, only a few have reported on the optimization of the production of organic solvent-tolerant proteases. Ironically, none has reported on thermostable organic solvent-tolerant protease to date. The aim of this study was to isolate the thermostable organic solvent-tolerant protease and identify the culture conditions which support its production. The bacteria of genus Bacillus are active producers of extra-cellular proteases, and the thermostability of enzyme production by Bacillus species has been well-studied by a number of researchers. In the present study, the Bacillus subtilis strain Rand was isolated from the contaminated soil found in Port Dickson, Malaysia.  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