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   1481414篇
  免费   27461篇
  国内免费   6919篇
电工技术   34322篇
综合类   6370篇
化学工业   268887篇
金属工艺   64122篇
机械仪表   41916篇
建筑科学   45722篇
矿业工程   11423篇
能源动力   50257篇
轻工业   109829篇
水利工程   14885篇
石油天然气   37671篇
武器工业   134篇
无线电   195953篇
一般工业技术   280267篇
冶金工业   151685篇
原子能技术   34021篇
自动化技术   168330篇
  2021年   15495篇
  2020年   11842篇
  2019年   14597篇
  2018年   15592篇
  2017年   14881篇
  2016年   21281篇
  2015年   17385篇
  2014年   28693篇
  2013年   87982篇
  2012年   34709篇
  2011年   46965篇
  2010年   42306篇
  2009年   50838篇
  2008年   44034篇
  2007年   41174篇
  2006年   44040篇
  2005年   38920篇
  2004年   40947篇
  2003年   40844篇
  2002年   40111篇
  2001年   36620篇
  2000年   35152篇
  1999年   33981篇
  1998年   40450篇
  1997年   36813篇
  1996年   33781篇
  1995年   29880篇
  1994年   28082篇
  1993年   27964篇
  1992年   26022篇
  1991年   23073篇
  1990年   23430篇
  1989年   22571篇
  1988年   21095篇
  1987年   19299篇
  1986年   18661篇
  1985年   22015篇
  1984年   22277篇
  1983年   20241篇
  1982年   19251篇
  1981年   19345篇
  1980年   17953篇
  1979年   18471篇
  1978年   17751篇
  1977年   17473篇
  1976年   18311篇
  1975年   16034篇
  1974年   15491篇
  1973年   15581篇
  1972年   13076篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
Mosquito-borne Zika virus (ZIKV) became a real threat to human health due to the lack of vaccine and effective antiviral treatment. The virus has recently been responsible for a global outbreak leading to millions of infected cases. ZIKV complications were highlighted in adults with Guillain–Barré syndrome and in newborns with increasing numbers of congenital disorders ranging from mild developmental delays to fatal conditions. The ability of ZIKV to establish a long-term infection in diverse organs including the kidneys has been recently documented but the consequences of such a viral infection are still debated. Our study aimed to determine whether the efficiency of ZIKV growth in kidney cells relates to glucose concentration. Human kidney HK-2 cells were infected with different ZIKV strains in presence of normal and high glucose concentrations. Virological assays showed a decrease in viral replication without modifying entry steps (viral binding, internalization, fusion) under high glucose conditions. This decrease replication was associated with a lower virus progeny and increased cell viability when compared to ZIKV-infected HK-2 cells in normal glucose concentration. In conclusion, we showed for the first time that an elevated glucose level influences ZIKV replication level with an effect on kidney cell survival.  相似文献   
142.
Multimedia Tools and Applications - Discovering the relevant web services for specific applications in the dynamically changing business world becomes very critical. Researchers have used many...  相似文献   
143.
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic...  相似文献   
144.
Mobile Networks and Applications - 5G/6G communication are first generation high speed wireless communication network which integrates the aerial data, terrestrial data and maritime data via...  相似文献   
145.
146.
Theoretical Foundations of Chemical Engineering - The effect of the electrolyte composition, mass-transfer conditions, pore diameter, interpore distance, and electric parameters on the formation of...  相似文献   
147.
Fluoro-substituted and heteroaromatic compounds are valuable intermediates for a variety of applications in pharma- and agrochemistry and synthetic chemistry. This study investigates the chemoenzymatic preparation of chiral alcohols bearing a heteroaromatic ring with an increasing degree of fluorination in α-position. Starting from readily available picoline derivatives prochiral α-halogenated acyl moieties were introduced with excellent selectivity and 64–95 % yield. The formed carbonyl group was subsequently reduced to the corresponding alcohols using the alcohol dehydrogenase from Lactobacillus kefir, yielding an enantiomeric excess of 95–>99 % and up to 98 % yield.  相似文献   
148.
Journal of Inorganic and Organometallic Polymers and Materials - This paper reports the performance of alizarin based SnO2 dye-sensitized solar cells. A novel template assisted method has been...  相似文献   
149.
Applied Composite Materials - Determining the impact behavior of adhesive joints allows the designing of high-strength joints. Therefore, the dynamic behavior of adhesive joints has recently become...  相似文献   
150.
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