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   368篇
  免费   12篇
电工技术   9篇
化学工业   126篇
金属工艺   1篇
机械仪表   14篇
建筑科学   14篇
能源动力   23篇
轻工业   39篇
水利工程   1篇
无线电   36篇
一般工业技术   66篇
冶金工业   24篇
原子能技术   4篇
自动化技术   23篇
  2023年   2篇
  2022年   26篇
  2021年   23篇
  2020年   16篇
  2019年   6篇
  2018年   12篇
  2017年   11篇
  2016年   10篇
  2015年   8篇
  2014年   13篇
  2013年   28篇
  2012年   22篇
  2011年   19篇
  2010年   17篇
  2009年   22篇
  2008年   26篇
  2007年   7篇
  2006年   16篇
  2005年   9篇
  2004年   7篇
  2003年   7篇
  2002年   2篇
  2001年   3篇
  2000年   3篇
  1999年   9篇
  1998年   4篇
  1997年   5篇
  1996年   5篇
  1995年   6篇
  1994年   4篇
  1993年   2篇
  1992年   1篇
  1991年   2篇
  1990年   1篇
  1988年   2篇
  1987年   4篇
  1986年   1篇
  1985年   1篇
  1984年   3篇
  1983年   4篇
  1982年   2篇
  1981年   1篇
  1980年   2篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
  1972年   2篇
排序方式: 共有380条查询结果,搜索用时 0 毫秒
111.
Filamentous fungi possess the extraordinary ability to digest complex biomasses and mineralize numerous xenobiotics, as consequence of their aptitude to sensing the environment and regulating their intra and extra cellular proteins, producing drastic changes in proteome and secretome composition. Recent advancement in proteomic technologies offers an exciting opportunity to reveal the fluctuations of fungal proteins and enzymes, responsible for their metabolic adaptation to a large variety of environmental conditions. Here, an overview of the most commonly used proteomic strategies will be provided; this paper will range from sample preparation to gel-free and gel-based proteomics, discussing pros and cons of each mentioned state-of-the-art technique. The main focus will be kept on filamentous fungi. Due to the biotechnological relevance of lignocellulose degrading fungi, special attention will be finally given to their extracellular proteome, or secretome. Secreted proteins and enzymes will be discussed in relation to their involvement in bio-based processes, such as biomass deconstruction and mycoremediation.  相似文献   
112.
Parkinson’s disease is one of the most common neurodegenerative disorders worldwide, characterized by a progressive loss of dopaminergic neurons mainly localized in the substantia nigra pars compacta. In recent years, the detailed analyses of both genetic and idiopathic forms of the disease have led to a better understanding of the molecular and cellular pathways involved in PD, pointing to the centrality of mitochondrial dysfunctions in the pathogenic process. Failure of mitochondrial quality control is now considered a hallmark of the disease. The peroxisome proliferator-activated receptor gamma coactivator 1 (PGC-1) family acts as a master regulator of mitochondrial biogenesis. Therefore, keeping PGC-1 level in a proper range is fundamental to guarantee functional neurons. Here we review the major findings that tightly bond PD and PGC-1s, raising important points that might lead to future investigations.  相似文献   
113.
Alongside their function in primary haemostasis and thrombo-inflammation, platelets are increasingly considered a bridge between mental, immunological and coagulation-related disorders. This review focuses on the link between platelets and the pathophysiology of major depressive disorder (MDD) and its most frequent comorbidities. Platelet- and neuron-shared proteins involved in MDD are functionally described. Platelet-related studies performed in the context of MDD, cardiovascular disease, and major neurodegenerative, neuropsychiatric and neurodevelopmental disorders are transversally presented from an epidemiological, genetic and functional point of view. To provide a complete scenario, we report the analysis of original data on the epidemiological link between platelets and depression symptoms suggesting moderating and interactive effects of sex on this association. Epidemiological and genetic studies discussed suggest that blood platelets might also be relevant biomarkers of MDD prediction and occurrence in the context of MDD comorbidities. Finally, this review has the ambition to formulate some directives and perspectives for future research on this topic.  相似文献   
114.
115.
In this paper, we present a texture classification procedure that makes use of a blind deconvolution approach. Specifically, the texture is modeled as the output of a linear system driven by a binary excitation. We show that features computed from one-dimensional slices extracted from the two-dimensional autocorrelation function (ACF) of the binary excitation allows representing the texture for rotation-invariant classification purposes. The two-dimensional classification problem is thus reconduced to a more simple one-dimensional one, which leads to a significant reduction of the classification procedure computational complexity.  相似文献   
116.
Guest desorption procedures for s‐PS clathrate samples, leading to formation and regeneration of the nanoporous δ phase, are compared. An extraction procedure, based on supercritical carbon dioxide, allows an easy and fast recovery of the guest molecules operating under relatively mild conditions (90–200 bar, 40°C) and generates a completely empty δ form, also starting from the most stable s‐PS clathrate forms. In agreement with a previously proposed crystal structure of the nanoporous δ form, X‐ray diffraction patterns of δ form powders obtained by this procedure do not show the peak, which is reduced but still apparent in samples extracted with previous procedures based on boiling solvents. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2077–2082, 1999  相似文献   
117.
Galectins are soluble β-D-galactoside-binding proteins whose implication in cancer progression and disease outcome makes them prominent targets for therapeutic intervention. In this frame, the development of small inhibitors that block selectively the activity of galectins represents an important strategy for cancer therapy which is, however, still relatively underdeveloped. To this end, we designed here a rationally and efficiently novel diglycosylated compound, characterized by a selenoglycoside bond and the presence of a lipophilic benzyl group at both saccharide residues. The relatively high binding affinity of the new compound to the carbohydrate recognition domain of two galectins, galectin 3 and galectin 9, its good antiproliferative and anti-migration activity towards melanoma cells, as well as its anti-angiogenesis properties, pave the way for its further development as an anticancer agent.  相似文献   
118.
Currently, sustainability represents a primary issue for construction industry. New material and technological solutions are widely proposed and investigated to meet sustainability requirements and natural fibers represent one of the most studied materials. The work presented here investigated the mechanical behavior of a sustainable composite system made by pozzolanic mortar reinforced with hemp fiber grids. To improve the durability of the system and in particular of the fibers in the pozzolanic mortar environment a latex coating was used. The objective of the study was to investigate the mechanical behavior of the proposed composite system and assess the feasibility of using the system for structural retrofit applications on existing structures. A mechanical characterization of the fibers was conducted and the effectiveness of the latex coating in improving the durability of the fibers was investigated. The mechanical behavior of the composite system was studied, through a three-point bending test program.  相似文献   
119.
In this paper, a novel gate-level strategy for designing Carry-Select adders is proposed. The strategy is more general than the previously proposed techniques, and accounts for the dependence of multiplexer delay on its fan-out. Moreover the strategy is simple and systematic, and is helpful for designing Carry-Select adders with a pencil-and-paper approach. An approximate expression of the minimum delay achievable is derived to estimate performance before carrying out the design.The proposed strategy is validated in more than 1000 adders. Analysis confirms that the strategy leads to a delay which is minimal in most cases, and always within 5.7%.  相似文献   
120.
Summary Orientation and crystallinity of isotactic polypropylene moulded products have been investigated by means of infrared microscopy. The experimental techniques are described elsewhere [ 1-31]. The previous application to film casting products and the application in this work to injection-moulded products confirms their usefulness in polymer science. Orientation and crystallinity distributions obtained for different samples are reported and briefly discussed.  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