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   328篇
  免费   17篇
  2023年   3篇
  2022年   13篇
  2021年   24篇
  2020年   8篇
  2019年   14篇
  2018年   12篇
  2017年   7篇
  2016年   9篇
  2015年   16篇
  2014年   13篇
  2013年   27篇
  2012年   28篇
  2011年   32篇
  2010年   16篇
  2009年   11篇
  2008年   12篇
  2007年   17篇
  2006年   17篇
  2005年   12篇
  2004年   14篇
  2003年   16篇
  2002年   12篇
  2001年   6篇
  2000年   1篇
  1998年   2篇
  1994年   1篇
  1993年   1篇
  1987年   1篇
排序方式: 共有345条查询结果,搜索用时 421 毫秒
11.
Plasmonics - Effect of different gold (Au) grating structures on light absorption in solar cell is investigated by finite elemental analysis using COMSOL multiphysics-RF module. The geometry of the...  相似文献   
12.
13.
Cluster Computing - In this study, a secure and coordinated blockchain based energy trading system for Electric Vehicles (EVs) is presented. The major goals of this study are to provide secure and...  相似文献   
14.
Eicosanoids are crucial downstream signals in the insect immune responses. Phospholipase A2 (PLA2) catalyzes phospholipids, the initial step in eicosanoid biosynthesis. In mammals, the biological roles of Ca2+-independent Phospholipase A2 (iPLA2) have been extensively studied; however, only a few studies have attempted to explore iPLA2 functions in insects. In this study, we identified two iPLA2 genes (designated as BmiPLA2A and BmiPLA2B) in the silkworm, Bombyx mori. BmiPLA2A had a 2427 base pair (bp) open reading frame (ORF) that coded for a protein with 808 amino acids. In contrast, BmiPLA2B had a 1731 bp ORF that coded for a protein with 576 amino acids. Domain analysis revealed that BmiPLA2A had six ankyrin repeat domains, but BmiPLA2B lacks these domains. BmiPLA2A and BmiPLA2B were transcribed widely in various tissues and developmental stages with different expression patterns. The administration of 20-hydroxyecdysone increased their expression levels in the epidermis and hemocytes. Furthermore, challenged with virus, fungus, Gram-negative bacteria, and Gram-positive bacteria induced the expression of BmiPLA2A and BmiPLA2B with variable degrees along with different time points. Our findings imply that BmiPLA2A and BmiPLA2B may have important biological roles in the development and innate immunity of B. mori.  相似文献   
15.
Biodiesel is considered as a potential alternative energy source, but problem exists with the quantity and quality of feedstock used for it. To improve the feedstock quality of biodiesel, a field experiment was conducted under natural conditions. Cultivar Thori of kasumbha was used in the experiment. Commercialized biofertilizers were applied at the rate of 20 kg per acre and chemical fertilizer (diammonium phosphate) was applied as half dose (15 kg/ha). Results indicated that number of leaf plant−1, leaf area, number of seeds capitulum−1 was significantly increased by biofertilizer treatment alone (BF) and combine treatment of biofertilizer and chemical fertilizer (BFCF). Agronomic traits such as plant height, no. of branches of a plant, no. of capitulum/plant was improved significantly by BF treatment over the control. Maximum 1000 seed weight (41%) and seed yield (23%) were recorded in half dose of chemical fertilizers treatment (CFH). Seed oil content and seed phenolics were significantly improved by BF and CF treatments while maximum biodiesel yield was recorded by BF treatment. Maximum oleic acid was recorded by BF treatment while other fatty acids being maximum in control except linoleic acid in BFCF treatment. Results for specific gravity were non-significant while acid value and free fatty acid contents were substantially reduced by BF treatment as compared to other treatments. Maximum value of iodine number was recorded in BFCF treatment while tocopherol contents were improved by BF treatment. It is inferred that biofertilizer treatment alone perform better as compared to other treatments and 50% chemical fertilizer can be replaced using biofertilizer which is a good approach for sustainable environmental-friendly agriculture.Keyword: Green energy, Biofuel, Biodiesel, Kasumbha, Biofertilizers, Fatty acid, NMR  相似文献   
16.
17.
We developed a SHIV/macaque model of transmission from infected dams to their infants. Ten pregnant dams were infected intravenously with 100 MID(50) of macaque-titered SHIV-SF162P3 during the second trimester. Nine infants were born; the seven surviving beyond day of birth suckled for 6 months. Four of nine infants were infected (transmission rate = 44.4%), with one infection in utero, and three intrapartum and/or immediately post-birth via suckling. Varying levels of binding and neutralizing antibodies were transplacentally transferred to infants. Passive antibodies were detected in plasma on the day of birth and persisted for 5 weeks. Infants infected at or after birth controlled acute and post-acute viremia. Exposure to maternal SHIV-SF162P3 during birth and suckling in the presence of autologous maternal neutralizing antibodies may have affected transmission or pathogenesis in the infants. This transmission model can allow investigation of key parameters involved in perinatal transmission of HIV.  相似文献   
18.
Structure-activity relationships of a novel series of fungal efflux pump inhibitors with respect to potentiation of the activity of fluconazole against strains of Candida albicans and Candida glabrata over-expressing ABC-type efflux pumps are systematically explored.  相似文献   
19.
Primary care practitioners recognize that genetics is relevant to their daily practice, for example, for detecting and managing the risk of multifactorial disorders and genetic reproductive risks, and, in future, for targeted drug therapy. However, they lack confidence in their ability to apply genetic approaches. In fact, genetics is already ingrained in current practice, and the development of appropriate guidelines and web-based information resources will help practitioners to make personalized genetic risk assessment a part of holistic, patient-oriented primary health care.  相似文献   
20.

Background  

ChaB is a putative regulator of ChaA, a Na+/H+ antiporter that also has Ca+/H+ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy.  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