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   1588736篇
  免费   27975篇
  国内免费   7061篇
电工技术   34705篇
综合类   6500篇
化学工业   275405篇
金属工艺   65545篇
机械仪表   45283篇
建筑科学   48128篇
矿业工程   11583篇
能源动力   50443篇
轻工业   123977篇
水利工程   16037篇
石油天然气   37858篇
武器工业   151篇
无线电   198873篇
一般工业技术   297582篇
冶金工业   204276篇
原子能技术   34283篇
自动化技术   173143篇
  2021年   15636篇
  2020年   12003篇
  2019年   14750篇
  2018年   17381篇
  2017年   16761篇
  2016年   22256篇
  2015年   17600篇
  2014年   28851篇
  2013年   88216篇
  2012年   37856篇
  2011年   51806篇
  2010年   44407篇
  2009年   52153篇
  2008年   47875篇
  2007年   45439篇
  2006年   46672篇
  2005年   41687篇
  2004年   43530篇
  2003年   43251篇
  2002年   41974篇
  2001年   39221篇
  2000年   37319篇
  1999年   37110篇
  1998年   57688篇
  1997年   46989篇
  1996年   40364篇
  1995年   33717篇
  1994年   31236篇
  1993年   31037篇
  1992年   26984篇
  1991年   24186篇
  1990年   24450篇
  1989年   23507篇
  1988年   22079篇
  1987年   20283篇
  1986年   19671篇
  1985年   22984篇
  1984年   22774篇
  1983年   20707篇
  1982年   19596篇
  1981年   19749篇
  1980年   18363篇
  1979年   18815篇
  1978年   18075篇
  1977年   18507篇
  1976年   20701篇
  1975年   16199篇
  1974年   15678篇
  1973年   15799篇
  1972年   13278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