全文获取类型
收费全文 | 3699篇 |
免费 | 292篇 |
国内免费 | 9篇 |
专业分类
电工技术 | 63篇 |
综合类 | 2篇 |
化学工业 | 1041篇 |
金属工艺 | 84篇 |
机械仪表 | 111篇 |
建筑科学 | 112篇 |
矿业工程 | 6篇 |
能源动力 | 133篇 |
轻工业 | 794篇 |
水利工程 | 33篇 |
石油天然气 | 19篇 |
无线电 | 215篇 |
一般工业技术 | 670篇 |
冶金工业 | 333篇 |
原子能技术 | 21篇 |
自动化技术 | 363篇 |
出版年
2024年 | 11篇 |
2023年 | 42篇 |
2022年 | 51篇 |
2021年 | 187篇 |
2020年 | 115篇 |
2019年 | 137篇 |
2018年 | 135篇 |
2017年 | 159篇 |
2016年 | 162篇 |
2015年 | 113篇 |
2014年 | 186篇 |
2013年 | 270篇 |
2012年 | 249篇 |
2011年 | 258篇 |
2010年 | 211篇 |
2009年 | 222篇 |
2008年 | 200篇 |
2007年 | 195篇 |
2006年 | 146篇 |
2005年 | 112篇 |
2004年 | 84篇 |
2003年 | 86篇 |
2002年 | 61篇 |
2001年 | 52篇 |
2000年 | 38篇 |
1999年 | 57篇 |
1998年 | 93篇 |
1997年 | 71篇 |
1996年 | 51篇 |
1995年 | 33篇 |
1994年 | 32篇 |
1993年 | 32篇 |
1992年 | 14篇 |
1991年 | 17篇 |
1990年 | 21篇 |
1989年 | 14篇 |
1988年 | 26篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1977年 | 4篇 |
1976年 | 7篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1964年 | 1篇 |
排序方式: 共有4000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
P. Carrasqueira H. Rocha J. M. Dias T. Ventura B. C. Ferreira M. C. Lopes 《International Transactions in Operational Research》2023,30(1):206-223
Radiation therapy is a technology-driven cancer treatment modality that has experienced significant advances over the last decades, due to multidisciplinary contributions that include engineering and computing. Recent technological developments allow the use of noncoplanar volumetric modulated arc therapy (VMAT), one of the most recent photon treatment techniques, in clinical practice. In this work, an automated noncoplanar arc trajectory optimization framework designed in two modular phases is presented. First, a noncoplanar beam angle optimization algorithm is used to obtain a set of noncoplanar irradiation directions. Then, anchored in these directions, an optimization strategy is proposed to compute an optimal arc trajectory. The computational experiments considered a pool of twelve difficult head-and-neck tumor cases. It was possible to observe that, for some of these cases, the optimized noncoplanar arc trajectories led to significant treatment planning quality improvements, when compared with coplanar VMAT treatment plans. Although these experiments were done in a research environment treatment planning software (matRad), the conclusions can be of interest for a clinical setting: automated procedures can simplify the current treatment workflow, produce high-quality treatment plans, making better use of human resources and allowing for unbiased comparisons between different treatment techniques. 相似文献
10.
Shamila Vibhushan Manuela Bratti Juan Eduardo Montero-Hernndez Alaa El Ghoneimi Marc Benhamou Nicolas Charles Eric Daugas Ulrich Blank 《International journal of molecular sciences》2021,22(1)
A sizable part (~2%) of the human genome encodes for proteases. They are involved in many physiological processes, such as development, reproduction and inflammation, but also play a role in pathology. Mast cells (MC) contain a variety of MC specific proteases, the expression of which may differ between various MC subtypes. Amongst these proteases, chymase represents up to 25% of the total proteins in the MC and is released from cytoplasmic granules upon activation. Once secreted, it cleaves the targets in the local tissue environment, but may also act in lymph nodes infiltrated by MC, or systemically, when reaching the circulation during an inflammatory response. MC have been recognized as important components in the development of kidney disease. Based on this observation, MC chymase has gained interest following the discovery that it contributes to the angiotensin-converting enzyme’s independent generation of angiotensin II, an important inflammatory mediator in the development of kidney disease. Hence, progress regarding its role has been made based on studies using inhibitors but also on mice deficient in MC protease 4 (mMCP-4), the functional murine counterpart of human chymase. In this review, we discuss the role and actions of chymase in kidney disease. While initially believed to contribute to pathogenesis, the accumulated data favor a more subtle view, indicating that chymase may also have beneficial actions. 相似文献