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   1482956篇
  免费   27471篇
  国内免费   6921篇
电工技术   34328篇
综合类   6370篇
化学工业   269189篇
金属工艺   64139篇
机械仪表   41937篇
建筑科学   45768篇
矿业工程   11424篇
能源动力   50269篇
轻工业   109942篇
水利工程   14886篇
石油天然气   37676篇
武器工业   134篇
无线电   195968篇
一般工业技术   280426篇
冶金工业   152471篇
原子能技术   34025篇
自动化技术   168396篇
  2021年   15511篇
  2020年   11843篇
  2019年   14603篇
  2018年   15602篇
  2017年   14894篇
  2016年   21296篇
  2015年   17391篇
  2014年   28704篇
  2013年   88020篇
  2012年   34749篇
  2011年   47016篇
  2010年   42324篇
  2009年   50864篇
  2008年   44082篇
  2007年   41222篇
  2006年   44072篇
  2005年   38944篇
  2004年   40977篇
  2003年   40865篇
  2002年   40131篇
  2001年   36629篇
  2000年   35162篇
  1999年   34017篇
  1998年   40685篇
  1997年   36921篇
  1996年   33870篇
  1995年   29921篇
  1994年   28119篇
  1993年   28012篇
  1992年   26032篇
  1991年   23086篇
  1990年   23441篇
  1989年   22581篇
  1988年   21108篇
  1987年   19312篇
  1986年   18671篇
  1985年   22027篇
  1984年   22285篇
  1983年   20252篇
  1982年   19256篇
  1981年   19349篇
  1980年   17957篇
  1979年   18474篇
  1978年   17760篇
  1977年   17498篇
  1976年   18353篇
  1975年   16039篇
  1974年   15493篇
  1973年   15586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