全文获取类型
收费全文 | 3982篇 |
免费 | 270篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 48篇 |
综合类 | 4篇 |
化学工业 | 900篇 |
金属工艺 | 43篇 |
机械仪表 | 76篇 |
建筑科学 | 134篇 |
矿业工程 | 11篇 |
能源动力 | 156篇 |
轻工业 | 630篇 |
水利工程 | 37篇 |
石油天然气 | 9篇 |
无线电 | 372篇 |
一般工业技术 | 569篇 |
冶金工业 | 204篇 |
原子能技术 | 38篇 |
自动化技术 | 1023篇 |
出版年
2024年 | 1篇 |
2023年 | 31篇 |
2022年 | 41篇 |
2021年 | 171篇 |
2020年 | 105篇 |
2019年 | 132篇 |
2018年 | 143篇 |
2017年 | 152篇 |
2016年 | 177篇 |
2015年 | 127篇 |
2014年 | 228篇 |
2013年 | 333篇 |
2012年 | 303篇 |
2011年 | 314篇 |
2010年 | 236篇 |
2009年 | 242篇 |
2008年 | 239篇 |
2007年 | 202篇 |
2006年 | 122篇 |
2005年 | 118篇 |
2004年 | 96篇 |
2003年 | 111篇 |
2002年 | 74篇 |
2001年 | 47篇 |
2000年 | 46篇 |
1999年 | 48篇 |
1998年 | 81篇 |
1997年 | 57篇 |
1996年 | 50篇 |
1995年 | 36篇 |
1994年 | 36篇 |
1993年 | 32篇 |
1992年 | 14篇 |
1991年 | 14篇 |
1990年 | 15篇 |
1989年 | 15篇 |
1988年 | 11篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1969年 | 1篇 |
排序方式: 共有4254条查询结果,搜索用时 15 毫秒
1.
Raquel Cano Jos L. Prez Liss Angarita Dvila ngel Ortega Yosselin Gmez Nereida Josefina Valero-Cedeo Heliana Parra Alexander Manzano Teresa Isabel Vliz Castro María P. Díaz Albornoz Gabriel Cano Joselyn Rojas-Quintero Maricarmen Chacín Valmore Bermúdez 《International journal of molecular sciences》2021,22(9)
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disorder, affecting around 25% of the population worldwide. It is a complex disease spectrum, closely linked with other conditions such as obesity, insulin resistance, type 2 diabetes mellitus, and metabolic syndrome, which may increase liver-related mortality. In light of this, numerous efforts have been carried out in recent years in order to clarify its pathogenesis and create new prevention strategies. Currently, the essential role of environmental pollutants in NAFLD development is recognized. Particularly, endocrine-disrupting chemicals (EDCs) have a notable influence. EDCs can be classified as natural (phytoestrogens, genistein, and coumestrol) or synthetic, and the latter ones can be further subdivided into industrial (dioxins, polychlorinated biphenyls, and alkylphenols), agricultural (pesticides, insecticides, herbicides, and fungicides), residential (phthalates, polybrominated biphenyls, and bisphenol A), and pharmaceutical (parabens). Several experimental models have proposed a mechanism involving this group of substances with the disruption of hepatic metabolism, which promotes NAFLD. These include an imbalance between lipid influx/efflux in the liver, mitochondrial dysfunction, liver inflammation, and epigenetic reprogramming. It can be concluded that exposure to EDCs might play a crucial role in NAFLD initiation and evolution. However, further investigations supporting these effects in humans are required. 相似文献
2.
Zia Muhammad Yousuf Irfan Otero Pablo Siddiqui Atif Poncela Javier 《Wireless Personal Communications》2021,116(2):1171-1193
Wireless Personal Communications - Underwater Wireless Sensor Networks (UWSNs) are playing a vital role in exploring the unseen underwater (UW) natural resources. However, performance evaluation of... 相似文献
3.
4.
5.
6.
Marta Gabasa Marselina Arshakyan Alejandro Llorente Lourdes Chuli-Peris Irina Pavelescu Antoni Xaubet Javier Pereda Jordi Alcaraz 《International journal of molecular sciences》2020,21(22)
Pro-inflammatory cytokines like interleukin-1β (IL-1β) are upregulated during early responses to tissue damage and are expected to transiently compromise the mechanical microenvironment. Fibroblasts are key regulators of tissue mechanics in the lungs and other organs. However, the effects of IL-1β on fibroblast mechanics and functions remain unclear. Here we treated human pulmonary fibroblasts from control donors with IL-1β and used Atomic Force Microscopy to unveil that IL-1β significantly reduces the stiffness of fibroblasts concomitantly with a downregulation of filamentous actin (F-actin) and alpha-smooth muscle (α-SMA). Likewise, COL1A1 mRNA was reduced, whereas that of collagenases MMP1 and MMP2 were upregulated, favoring a reduction of type-I collagen. These mechanobiology changes were functionally associated with reduced proliferation and enhanced migration upon IL-1β stimulation, which could facilitate lung repair by drawing fibroblasts to sites of tissue damage. Our observations reveal that IL-1β may reduce local tissue rigidity by acting both intracellularly and extracellularly through the downregulation of fibroblast contractility and type I collagen deposition, respectively. These IL-1β-dependent mechanical effects may enhance lung repair further by locally increasing pulmonary tissue compliance to preserve normal lung distension and function. Moreover, our results support that IL-1β provides innate anti-fibrotic protection that may be relevant during the early stages of lung repair. 相似文献
7.
8.
Bill Robert Fleck Martin Troya Javier Mayerhofer Tanja Wimmer Manuel 《Software and Systems Modeling》2019,18(2):1017-1046
Software and Systems Modeling - Many model transformation scenarios require flexible execution strategies as they should produce models with the highest possible quality. At the same time,... 相似文献
9.
Antonio Camarano Javier Narciso Donatella Giuranno 《Journal of the European Ceramic Society》2019,39(14):3959-3970
Reactivity between SiC and Ir as a function of SiC-crystallinity was investigated by diffusion bonding technique under a vacuum and over the temperature range of 1200–1450 °C. As reaction products, various Ir-silicides and free unreacted-C were detected. Reactivity is strongly affected by the temperature and SiC-crystallinity involving a series of interactions, from “no reaction” to “massive exothermic reactions”. In particular, interfacial phenomena are more pronounced by the presence of defects and grain boundaries.Solid state reactions result in formation of fine C-precipitates rearranged in a quasi-periodic microstructure. On the contrary, clustering of highly ordered C-precipitates (C-graphitized) occurs after “massive reactions” take place.A relationship between the degree of graphitization (from 1 to multi-layers of graphene), temperature and SiC crystallinity was found by Raman spectroscopy. 2D-layering phenomenon is enhanced in polycrystalline SiC at high temperature. 相似文献
10.