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   1526970篇
  免费   28008篇
  国内免费   7098篇
电工技术   34823篇
综合类   6435篇
化学工业   271437篇
金属工艺   65400篇
机械仪表   43953篇
建筑科学   46576篇
矿业工程   11651篇
能源动力   50439篇
轻工业   114913篇
水利工程   15485篇
石油天然气   38140篇
武器工业   149篇
无线电   198153篇
一般工业技术   288516篇
冶金工业   171181篇
原子能技术   34277篇
自动化技术   170548篇
  2021年   15675篇
  2020年   12010篇
  2019年   14763篇
  2018年   17329篇
  2017年   16797篇
  2016年   22155篇
  2015年   17612篇
  2014年   28861篇
  2013年   88321篇
  2012年   36106篇
  2011年   49602篇
  2010年   43973篇
  2009年   52273篇
  2008年   45992篇
  2007年   43578篇
  2006年   44877篇
  2005年   40391篇
  2004年   41920篇
  2003年   41684篇
  2002年   40671篇
  2001年   37367篇
  2000年   35767篇
  1999年   35016篇
  1998年   46947篇
  1997年   40548篇
  1996年   36167篇
  1995年   31263篇
  1994年   29143篇
  1993年   29073篇
  1992年   26316篇
  1991年   23461篇
  1990年   23762篇
  1989年   22913篇
  1988年   21445篇
  1987年   19625篇
  1986年   18990篇
  1985年   22334篇
  1984年   22450篇
  1983年   20402篇
  1982年   19346篇
  1981年   19484篇
  1980年   18113篇
  1979年   18587篇
  1978年   17855篇
  1977年   17828篇
  1976年   18996篇
  1975年   16138篇
  1974年   15570篇
  1973年   15665篇
  1972年   13163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