全文获取类型
收费全文 | 4193篇 |
免费 | 271篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 46篇 |
综合类 | 3篇 |
化学工业 | 1084篇 |
金属工艺 | 82篇 |
机械仪表 | 155篇 |
建筑科学 | 105篇 |
矿业工程 | 4篇 |
能源动力 | 204篇 |
轻工业 | 444篇 |
水利工程 | 37篇 |
石油天然气 | 12篇 |
无线电 | 336篇 |
一般工业技术 | 782篇 |
冶金工业 | 179篇 |
原子能技术 | 26篇 |
自动化技术 | 973篇 |
出版年
2024年 | 8篇 |
2023年 | 61篇 |
2022年 | 157篇 |
2021年 | 167篇 |
2020年 | 152篇 |
2019年 | 143篇 |
2018年 | 176篇 |
2017年 | 153篇 |
2016年 | 194篇 |
2015年 | 155篇 |
2014年 | 217篇 |
2013年 | 343篇 |
2012年 | 339篇 |
2011年 | 352篇 |
2010年 | 260篇 |
2009年 | 197篇 |
2008年 | 211篇 |
2007年 | 183篇 |
2006年 | 148篇 |
2005年 | 101篇 |
2004年 | 119篇 |
2003年 | 83篇 |
2002年 | 89篇 |
2001年 | 49篇 |
2000年 | 35篇 |
1999年 | 21篇 |
1998年 | 39篇 |
1997年 | 49篇 |
1996年 | 30篇 |
1995年 | 16篇 |
1994年 | 21篇 |
1993年 | 20篇 |
1992年 | 15篇 |
1991年 | 7篇 |
1990年 | 15篇 |
1989年 | 14篇 |
1988年 | 7篇 |
1987年 | 14篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 14篇 |
1983年 | 13篇 |
1982年 | 6篇 |
1981年 | 10篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 8篇 |
1976年 | 4篇 |
1974年 | 3篇 |
排序方式: 共有4472条查询结果,搜索用时 15 毫秒
1.
David Diaz Elisa Lopez-Dolado Sergio Haro Jorge Monserrat Carlos Martinez-Alonso Dimitrios Balomeros Agustín Albillos Melchor Alvarez-Mon 《International journal of molecular sciences》2021,22(2)
Our aim was to investigate the subset distribution and function of circulating monocytes, proinflammatory cytokine levels, gut barrier damage, and bacterial translocation in chronic spinal cord injury (SCI) patients. Thus, 56 SCI patients and 28 healthy donors were studied. The levels of circulating CD14+highCD16−, CD14+highCD16+, and CD14+lowCD16+ monocytes, membrane TLR2, TLR4, and TLR9, phagocytic activity, ROS generation, and intracytoplasmic TNF-α, IL-1, IL-6, and IL-10 after lipopolysaccharide (LPS) stimulation were analyzed by polychromatic flow cytometry. Serum TNF-α, IL-1, IL-6 and IL-10 levels were measured by Luminex and LPS-binding protein (LBP), intestinal fatty acid-binding protein (I-FABP) and zonulin by ELISA. SCI patients had normal monocyte counts and subset distribution. CD14+highCD16− and CD14+highCD16+ monocytes exhibited decreased TLR4, normal TLR2 and increased TLR9 expression. CD14+highCD16− monocytes had increased LPS-induced TNF-α but normal IL-1, IL-6, and IL-10 production. Monocytes exhibited defective phagocytosis but normal ROS production. Patients had enhanced serum TNF-α and IL-6 levels, normal IL-1 and IL-10 levels, and increased circulating LBP, I-FABP, and zonulin levels. Chronic SCI patients displayed impaired circulating monocyte function. These patients exhibited a systemic proinflammatory state characterized by enhanced serum TNF-α and IL-6 levels. These patients also had increased bacterial translocation and gut barrier damage. 相似文献
2.
Fabiana Piscitelli Roberto Coccurello Antonio Totaro Alessandro Leuti Giacomo Giacovazzo Roberta Verde Emanuela Rossi Michele Podaliri Vulpiani Nicola Ferri Roberto Giacominelli Stuffler Vincenzo Di Marzo Sergio Oddi Tiziana Bisogno Mauro Maccarrone 《European Journal of Lipid Science and Technology》2019,121(10)
3.
4.
5.
An intertwined supply network (ISN) is an entirety of interconnected supply chains (SC) which, in their integrity secure the provision of society and markets with goods and services. The ISNs are open systems with structural dynamics since the firms may exhibit multiple behaviours by changing the buyer-supplier roles in interconnected or even competing SCs. From the positions of resilience, the ISNs as a whole provide services to society (e.g. food service, mobility service or communication service) which are required to ensure a long-term survival. The analysis of survivability at the level of ISN requires a consideration at a large scale as resilience of individual SCs. The recent example of coronavirus COVID-19 outbreak clearly shows the necessity of this new perspective. Our study introduces a new angle in SC resilience research when a resistance to extraordinary disruptions needs to be considered at the scale of viability. We elaborate on the integrity of the ISN and viability. The contribution of our position study lies in a conceptualisation of a novel decision-making environment of ISN viability. We illustrate the viability formation through a dynamic game-theoretic modelling of a biological system that resembles the ISN. We discuss some future research areas. 相似文献
6.
7.
8.
Graded evolution of anisotropic microstructure during sintering from crystal-oriented powder compact
Shoko Baba Alexandre Maître Nicolas Pradeilles Guy Antou Nobuo Saito Satoshi Tanaka 《International Journal of Applied Ceramic Technology》2020,17(2):677-684
Anisotropic sintering, including shrinkage and grain growth, was examined for c-axis-oriented (Sr,Ca)2NaNb5O15 (SCNN) ceramics, which were prepared by colloidal processing under a magnetic field. In the c-axis-oriented SCNN powder compact, shrinkage and grain growth along the c-axis were higher than those along the a-axis. The anisotropic microstructural development was clearly associated with anisotropic sintering shrinkage. X-ray diffraction, scanning electron microscopy, and energy back scattering diffraction showed that the grain growth of oriented particles by including random grains contribute to the development of the oriented microstructure. Finally, the highly crystal-oriented SCNN ceramics with a densified microstructure were obtained through anisotropic sintering. These results clearly showed the potential to develop a well-defined anisotropic microstructure during sintering by designing and controlling the particle packing structure in a powder compact. 相似文献
9.
10.
Parameshvyas Laxminarayan Sergio A Alvarez Carolina Ruiz Majaz Moonis 《IEEE transactions on information technology in biomedicine》2006,10(3):440-450
We introduce a specialized association rule mining technique that can extract patterns from complex sleep data comprising polysomnographic recordings, clinical summaries, and sleep questionnaire responses. The rules mined can describe associations among temporally annotated events and questionnaire or summary data; e.g., the likelihood that an occurrence of a rapid eye movement (REM) sleep stage during the second 100 sleep epochs of the night is associated with moderate caffeine intake. We use chi2 analysis to ensure statistical significance of the mined rules at the level P < 0.05. Our results, obtained by mining sleep-related data from 242 human subjects, reveal clinically interesting associations among the polysomnographic and summary variables. Our experience suggests that association mining may also be useful for selection of variables prior to using logistic regression. 相似文献