全文获取类型
收费全文 | 8451篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
综合类 | 5篇 |
化学工业 | 33篇 |
金属工艺 | 5篇 |
建筑科学 | 3篇 |
轻工业 | 11篇 |
水利工程 | 1篇 |
石油天然气 | 3篇 |
武器工业 | 1篇 |
无线电 | 8篇 |
一般工业技术 | 11篇 |
冶金工业 | 8357篇 |
原子能技术 | 1篇 |
自动化技术 | 13篇 |
出版年
2020年 | 3篇 |
2016年 | 1篇 |
2014年 | 4篇 |
2013年 | 3篇 |
2012年 | 4篇 |
2011年 | 2篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 4篇 |
2007年 | 8篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 11篇 |
2003年 | 12篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 277篇 |
1998年 | 2676篇 |
1997年 | 1480篇 |
1996年 | 947篇 |
1995年 | 547篇 |
1994年 | 419篇 |
1993年 | 526篇 |
1992年 | 61篇 |
1991年 | 102篇 |
1990年 | 99篇 |
1989年 | 87篇 |
1988年 | 93篇 |
1987年 | 91篇 |
1986年 | 95篇 |
1985年 | 65篇 |
1984年 | 1篇 |
1983年 | 9篇 |
1982年 | 35篇 |
1981年 | 37篇 |
1980年 | 77篇 |
1979年 | 2篇 |
1978年 | 12篇 |
1977年 | 181篇 |
1976年 | 431篇 |
1975年 | 9篇 |
1963年 | 2篇 |
1955年 | 7篇 |
1954年 | 1篇 |
排序方式: 共有8453条查询结果,搜索用时 15 毫秒
81.
82.
B Elliott C Richardson J Winderbaum JA Nickoloff M Jasin 《Canadian Metallurgical Quarterly》1998,18(1):93-101
A new assay termed the dome disappearance method for classical swine fever virus (CSFV) using FS-L3 cells with serum-free culture medium was developed. The CSFV live vaccine GPE- strain grows well and shows a slight cytopathic effect (CPE) in FS-L3 cells. This CPE results in the disappearance of the unique fluid-filled multicellular domes on a single monolayer of FS-L3 cells. By using this phenomenon, dome disappearance, as a marker of infection, it was possible to determine the titers of CSFV and its neutralizing antibody. The virus titer determined by this method shows a good correlation with that determined by immunochemical and interference methods. Furthermore, the amount of neutralizing antibody measured by this method also correlated with that measured by the Exaltation of Newcastle Disease Virus (END) neutralizing method. The dome disappearance method developed in this experiment is a simple and safe procedure and has the great advantage that bovine serum, which may contain antibody against bovine viral diarrhea virus, is not necessary for the cultivation of FS-L3 cells. 相似文献
83.
Efficacies of the 5-hydroxytryptamine (serotonin) 5-HT3 receptor (5-HT3R) agonists 2-methyl-5-HT, dopamine, and m-chlorophenylbiguanide on 5-HT3R native to N1E-115 cells and on homopentameric 5-HT3R expressed in Xenopus oocytes were determined relative to that of 5-HT. Efficacies of 2-methyl-5-HT and dopamine on 5-HT3R native to differentiated N1E-115 cells are high (54 and 36%) as compared with their efficacies on homopentameric 5-HT3R-A(L) and 5-HT3R-A(S) receptors expressed in oocytes (4-8%). m-Chlorophenylbiguanide does not distinguish between 5-HT3R in N1E-115 cells and in oocytes. The distinct pharmacological profile of 5-HT3R native to differentiated N1E-115 cells is conserved when poly(A)+ mRNA from these cells is expressed in oocytes. The results indicate that, apart from the known 5-HT3R subunits, N1E-115 cells express additional proteins involved in 5-HT3R function. 相似文献
84.
85.
86.
在连铸实验装置上 ,以低熔点Pb Sn Bi合金和硅油分别模拟钢液和保护渣 ,对流动控制结晶器内钢液流动规律进行了实验研究。结果表明 ,流动控制结晶器能够控制弯月面的波动和水口区域的流动状态 ,对改善连铸坯表面及内部质量具有良好的作用。 相似文献
87.
88.
Björn Crüts Ludo van Etten Håkan Törnqvist Anders Blomberg Thomas Sandström Nicholas L Mills Paul JA Borm 《Particle and fibre toxicology》2008,5(1):4
Background
Ambient particulate matter and nanoparticles have been shown to translocate to the brain, and potentially influence the central nervous system. No data are available whether this may lead to functional changes in the brain. 相似文献89.
90.
Ken Donaldson Paul JA Borm Vincent Castranova Mary Gulumian 《Particle and fibre toxicology》2009,6(1):13
In vitro studies with particles are a major staple of particle toxicology, generally used to investigate mechanisms and better understand the molecular events underlying cellular effects. However, there is ethical and financial pressure in nanotoxicology, the new sub-specialty of particle toxicology, to avoid using animals. Therefore an increasing amount of studies are being published using in vitro approaches and such studies require careful interpretation. We point out here that 3 different conventional pathogenic particle types, PM10, asbestos and quartz, which cause diverse pathological effects, have been reported to cause very similar oxidative stress effects in cells in culture. We discuss the likely explanation and implications of this apparent paradox, and its relevance for testing in nanotoxicology. 相似文献