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   1542667篇
  免费   27916篇
  国内免费   7034篇
电工技术   34514篇
综合类   6430篇
化学工业   271957篇
金属工艺   64863篇
机械仪表   43816篇
建筑科学   47370篇
矿业工程   11516篇
能源动力   50360篇
轻工业   118784篇
水利工程   15729篇
石油天然气   37697篇
武器工业   136篇
无线电   197601篇
一般工业技术   290655篇
冶金工业   180816篇
原子能技术   34095篇
自动化技术   171278篇
  2021年   15601篇
  2020年   11956篇
  2019年   14739篇
  2018年   16238篇
  2017年   15571篇
  2016年   21814篇
  2015年   17527篇
  2014年   28857篇
  2013年   88243篇
  2012年   36580篇
  2011年   49783篇
  2010年   43407篇
  2009年   51521篇
  2008年   46248篇
  2007年   43689篇
  2006年   45745篇
  2005年   40742篇
  2004年   42494篇
  2003年   42297篇
  2002年   41256篇
  2001年   38358篇
  2000年   36489篇
  1999年   35845篇
  1998年   50679篇
  1997年   42681篇
  1996年   37576篇
  1995年   32086篇
  1994年   29813篇
  1993年   29665篇
  1992年   26534篇
  1991年   23724篇
  1990年   23967篇
  1989年   23062篇
  1988年   21692篇
  1987年   19754篇
  1986年   19214篇
  1985年   22574篇
  1984年   22613篇
  1983年   20586篇
  1982年   19460篇
  1981年   19579篇
  1980年   18202篇
  1979年   18717篇
  1978年   17942篇
  1977年   18013篇
  1976年   19363篇
  1975年   16181篇
  1974年   15635篇
  1973年   15750篇
  1972年   13215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