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   235篇
  免费   19篇
电工技术   2篇
化学工业   73篇
金属工艺   10篇
机械仪表   4篇
建筑科学   15篇
能源动力   9篇
轻工业   35篇
水利工程   2篇
无线电   14篇
一般工业技术   35篇
冶金工业   20篇
原子能技术   2篇
自动化技术   33篇
  2023年   4篇
  2022年   4篇
  2021年   14篇
  2020年   7篇
  2019年   10篇
  2018年   4篇
  2017年   4篇
  2016年   8篇
  2015年   14篇
  2014年   6篇
  2013年   16篇
  2012年   24篇
  2011年   21篇
  2010年   16篇
  2009年   9篇
  2008年   20篇
  2007年   15篇
  2006年   9篇
  2005年   13篇
  2004年   8篇
  2003年   6篇
  2002年   3篇
  2001年   4篇
  2000年   2篇
  1999年   3篇
  1998年   4篇
  1997年   2篇
  1995年   3篇
  1993年   1篇
排序方式: 共有254条查询结果,搜索用时 46 毫秒
91.
Four studies examined gender differences in self-construals and the role of social comparison in generating these differences. Consistent with previous research, Study 1 (N=461) showed that women define themselves as higher in relational interdependence than men, and men define themselves as higher in independence/agency than women. Study 2 (N=301) showed that within-gender social comparison decreases gender differences in self-construals relative to a control condition, whereas between-genders comparison increases gender differences on both relational interdependence and independence/agency. Studies 3 (N=169) and 4 (N=278) confirmed these findings and showed that changing self-construal changes gender differences in social dominance orientation. Across the 4 studies, strong evidence for the role of in-group stereotyping as mediator of the effect of gender on self-construal was observed on the relational dimension but not on the agentic dimension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
93.
94.
The increasing resistance of Plasmodium falciparum to the most commonly used antimalarial drugs makes it necessary to identify new therapeutic targets. The telomeres of the parasite could constitute an attractive target. They are composed of repetitions of a degenerate motif ((5')GGGTTYA(3'), where Y is T or C), different from the human one ((5')GGGTTA(3')). In this report we investigate the possibility of targeting Plasmodium telomeres with G-quadruplex ligands. Through solution hybridisation assays we provide evidence of the existence of a telomeric 3' G-overhang in P. falciparum genomic DNA. Through UV spectroscopy studies we demonstrate that stable G-quadruplex structures are formed at physiological temperature by sequences composed of the degenerate Plasmodium telomeric motif. Through a FRET melting assay we show stabilisation of Plasmodium telomeric G-quadruplexes by a variety of ligands. Many of the tested ligands display strong quadruplex versus duplex selectivity, but show little discrimination between human and Plasmodium telomeric quadruplexes.  相似文献   
95.
Biological Functions and Metabolism of Oleoylethanolamide   总被引:2,自引:0,他引:2  
The present review is focused on the metabolism and the emerging roles of oleoylethanolamide (OEA) with emphasis on its effects on food intake control and lipid metabolism. The biological mechanism of action, including a non-genomic effect mediated through peroxisome proliferator-activated receptor alpha (PPAR-alpha) and transient receptor potential vanilloid type 1 (TRPV1) receptor, is discussed. The research related to fatty acid ethanolamides has been focused until recently on anandamide and its interaction with cannabinoid receptor subtype 1. The roles of other N-acyl ethanolamine fatty acid derivatives have been neglected until it was demonstrated that OEA can modulate food intake control through interaction with PPAR-alpha. Further investigations demonstrated that OEA modulates lipid and glucose metabolism, and recent study confirmed that OEA is an antagonist of TRVP1. It has been demonstrated that OEA has beneficial effects on health by inducing food intake control, lipid beta-oxidation, body weight loss and analgesic effects. The investigation of the mechanism of action revealed that OEA activates PPAR-alpha and stimulates the vagal nerve through the capsaicin receptor TRPV1. Pre-clinical studies showed that OEA remains active when administered orally.  相似文献   
96.
European corn borer larvae detect and avoid feeding in the presence of phytoecdysteroids (PEs) such as 20-hydroxyecdysone (20E). Therefore, we hypothesized that females would have taste receptors similar to larvae and avoid laying eggs in the presence of 20E. We found female-specific taste sensilla on the tarsi that respond to 20E at concentrations as low as 10−6 M, a threshold comparable to that of larvae. However, in choice tests, females laid a similar number of eggs on 20E-treated and on nontreated artificial substrates (filter paper, glass, and nylon), although they spent significantly more time in behavioral sequences related to substrate assessment when 20E was present. In contrast, when given a choice between maize plants (eight leaves) sprayed with 20E or only the solvent, females laid 70% fewer eggs on the treated than on control plants. These observations suggest that other chemical cues of plant origin must be present at the same time as 20E for females to modify their oviposition behavior.  相似文献   
97.
98.
Aurora kinases play an essential role in mitotic progression and are potentially druggable targets in cancer therapy. We identified benzo[e]pyridoindoles (BePI) as powerful aurora kinase inhibitors. Their efficiency was demonstrated both in enzymatic inhibition studies and in cell culture assays. New BePI molecules were synthesized, and a structure–activity relationship study was conducted with the aim of improving the activity and solubility of the lead compound. Tetracyclic BePI derivatives are characterized by a particular curved shape, and the presence of an oxo group on the pyridine ring was found to be required for aurora kinase B inhibition. New hydrosoluble benzo[e]pyridoindolones were subsequently designed, and their efficacy was tested by a combination of cell‐cycle analysis and time‐lapse experiments in live cells. The most active BePI derivative, 13 b , inhibited the cell cycle, drove cells to polyploidy, and eventually induced apoptosis. It exhibited high antiproliferative activity in HeLa cells with an IC50 value of 63 nM . Relative to compounds tested in clinical trials, this antiproliferative potency places 13 b among the top 10 aurora kinase inhibitors. Our results justify further in vivo evaluation in preclinical animal models of cancer.  相似文献   
99.
Technical renewable poly(l ‐lactide) (PLA)‐based blends represent an elegant way to achieve attractive properties for engineering applications. Recently, the miscibility between PLA and poly(methyl methacrylate) (PMMA) gave rise to new formulations with enhanced thermo‐mechanical properties but their high brittleness still remains a challenge to be overcome. This work here focuses on rubber‐toughened PLA/PMMA formulations for injection‐molding processes upon the addition of a commercially available ethylene‐acrylate impact modifier (BS). The miscibility between PLA and PMMA is not altered by the presence of BS but the incorporation of BS (17% by weight) into a PLA/PMMA matrix could enhance both ductility and toughness of PLA/PMMA blends for PMMA content up to 50 wt %. An optimum range of particle sizes (dn ~0.5 µm) of the dispersed domains for high impact toughness is identified. These bio‐based ternary blends appear as promising alternatives to petro‐sourced blends such as ABS‐based blends in engineering injection‐molding parts. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43402.  相似文献   
100.
Raw milk, raw milk cheeses, and raw ground meat have been implicated in Escherichia coli O157:H7 outbreaks. Developing methods to detect these bacteria in raw milk and meat products is a major challenge for food safety. The aim of our study was to develop a real-time PCR assay to detect E. coli O157:H7 in raw milk cheeses and raw ground meat. Well-known primers targeting a mutation at position +93 of the uidA gene in E. coli O157:H7 were chosen, and a specific TaqMan-minor groove binder probe was designed. This probe targets another mutation, at position +191 of the uidA gene in E. coli O157:H7. The first step in the study was to evaluate the specificity of this probe with 156 different O157:H7/NM strains and 48 non-O157:H7/NM strains of E. coli. The sensitivity of the method was evaluated by pre- and postinoculation of cheeses and meat enrichments with different E. coli O157:H7 strains. All the E. coli O157:H7 isolates tested were positive, and none of the other bacteria were detected. Our results indicate that this method is sensitive enough to detect 10(2) E. coli O157:H7 isolates per ml of cheese or meat enrichment broth (24 h at 41.5° C) and is more sensitive than the International Organization for Standardization reference method. We can conclude that this new real-time PCR protocol is a useful tool for rapid, specific, and sensitive detection of E. coli O157:H7 in raw milk and raw ground meat products.  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