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   2327篇
  免费   44篇
  国内免费   4篇
电工技术   171篇
化学工业   519篇
金属工艺   31篇
机械仪表   57篇
建筑科学   25篇
矿业工程   2篇
能源动力   88篇
轻工业   208篇
水利工程   2篇
石油天然气   5篇
无线电   230篇
一般工业技术   327篇
冶金工业   497篇
原子能技术   76篇
自动化技术   137篇
  2023年   7篇
  2022年   27篇
  2021年   48篇
  2020年   16篇
  2019年   21篇
  2018年   26篇
  2017年   19篇
  2016年   33篇
  2015年   38篇
  2014年   44篇
  2013年   136篇
  2012年   77篇
  2011年   102篇
  2010年   73篇
  2009年   100篇
  2008年   102篇
  2007年   86篇
  2006年   71篇
  2005年   62篇
  2004年   56篇
  2003年   77篇
  2002年   62篇
  2001年   50篇
  2000年   37篇
  1999年   60篇
  1998年   196篇
  1997年   126篇
  1996年   97篇
  1995年   70篇
  1994年   46篇
  1993年   58篇
  1992年   24篇
  1991年   8篇
  1990年   18篇
  1989年   32篇
  1988年   15篇
  1987年   15篇
  1986年   24篇
  1985年   21篇
  1984年   18篇
  1983年   22篇
  1982年   12篇
  1981年   17篇
  1980年   17篇
  1978年   14篇
  1977年   22篇
  1976年   27篇
  1974年   9篇
  1973年   5篇
  1972年   5篇
排序方式: 共有2375条查询结果,搜索用时 0 毫秒
61.
KIT is a type-III receptor tyrosine kinase that contributes to cell signaling in various cells. Since KIT is activated by overexpression or mutation and plays an important role in the development of some cancers, such as gastrointestinal stromal tumors and mast cell disease, molecular therapies targeting KIT mutations are being developed. In acute myeloid leukemia (AML), genome profiling via next-generation sequencing has shown that several genes that are mutated in patients with AML impact patients’ prognosis. Moreover, it was suggested that precision-medicine-based treatment using genomic data will improve treatment outcomes for AML patients. This paper presents (1) previous studies regarding the role of KIT mutations in AML, (2) the data in AML with KIT mutations from the HM-SCREEN-Japan-01 study, a genome profiling study for patients newly diagnosed with AML who are unsuitable for the standard first-line treatment (unfit) or have relapsed/refractory AML, and (3) new therapies targeting KIT mutations, such as tyrosine kinase inhibitors and heat shock protein 90 inhibitors. In this era when genome profiling via next-generation sequencing is becoming more common, KIT mutations are attractive novel molecular targets in AML.  相似文献   
62.
针对亚洲文脉下的高密度城市环境,提出“亚洲城市主义”作为一种新的研究和设计模式,并提出“一席之地”的概念作为环境设计中的焦点。研究关注的是“街道社会生态”,特别是在某一时刻街道上循环的事物、活动和空间结构的一幕最小的互相依赖图景,称作“社会即景”,倡导为高密度城市环境作契合文化内涵的设计。  相似文献   
63.
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy.  相似文献   
64.
We have characterized the electronic structure of FeSe1−xTex for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe.  相似文献   
65.
In this paper we establish the exact solution for a hollow sphere with a rigid-plastic pressure-sensitive matrix and subjected to hydrostatic tension or compression. The matrix is assumed to obey to a parabolic Mises–Schleicher criterion. The closed-form expressions of the velocity field and of the stress field are provided. These exact solutions, expressed by means of the Lambert W function, allow to assess and discuss existing results.  相似文献   
66.
67.
This paper first reviews the earthquakes that occurred since 1995 and then outlines the significant lessons learnt from disasters. The discussion then goes into the induced development of engineering practices that were triggered by those disasters. It is clear that major development occurred in design philosophies, soil improvement, and facilities for research. The last section of this paper addresses the compound effects of earthquakes and rainfall that may make the extent of the disasters worse.  相似文献   
68.
69.
70.
The phase transformation behavior of a thermally grown oxide scale of FeO on pure-Fe and an Fe–2wt%Au alloy was investigated. Particular attention was paid to formation of a magnetite seam, which is the Fe3O4 layer formed at the FeO/alloy interface at an initial stage of the phase transformation, since it has important effects on the overall phase transformation of FeO scale. A thin Au(Fe) layer was found to develop on the Fe–Au alloy at the FeO/alloy interface after 32 min of oxidation at 750 °C in air. This Au(Fe) layer prevented formation of a magnetite seam and accelerated the FeO eutectoid reaction. The Au(Fe) layer acted as a “chemical diffusion barrier” for inward diffusion of Fe from the FeO to the alloy substrate across the FeO/alloy interface and prevented magnetite seam formation.  相似文献   
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