全文获取类型
收费全文 | 2325篇 |
免费 | 110篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 11篇 |
综合类 | 1篇 |
化学工业 | 385篇 |
金属工艺 | 26篇 |
机械仪表 | 38篇 |
建筑科学 | 130篇 |
矿业工程 | 11篇 |
能源动力 | 35篇 |
轻工业 | 421篇 |
水利工程 | 13篇 |
石油天然气 | 15篇 |
无线电 | 102篇 |
一般工业技术 | 285篇 |
冶金工业 | 618篇 |
原子能技术 | 3篇 |
自动化技术 | 347篇 |
出版年
2023年 | 16篇 |
2022年 | 23篇 |
2021年 | 36篇 |
2020年 | 26篇 |
2019年 | 44篇 |
2018年 | 39篇 |
2017年 | 43篇 |
2016年 | 45篇 |
2015年 | 38篇 |
2014年 | 63篇 |
2013年 | 178篇 |
2012年 | 79篇 |
2011年 | 140篇 |
2010年 | 112篇 |
2009年 | 95篇 |
2008年 | 126篇 |
2007年 | 127篇 |
2006年 | 113篇 |
2005年 | 91篇 |
2004年 | 74篇 |
2003年 | 77篇 |
2002年 | 79篇 |
2001年 | 44篇 |
2000年 | 47篇 |
1999年 | 43篇 |
1998年 | 42篇 |
1997年 | 37篇 |
1996年 | 44篇 |
1995年 | 30篇 |
1994年 | 51篇 |
1993年 | 40篇 |
1992年 | 24篇 |
1991年 | 12篇 |
1990年 | 34篇 |
1989年 | 33篇 |
1988年 | 24篇 |
1987年 | 28篇 |
1986年 | 29篇 |
1985年 | 22篇 |
1984年 | 27篇 |
1983年 | 22篇 |
1982年 | 13篇 |
1981年 | 15篇 |
1980年 | 13篇 |
1979年 | 11篇 |
1978年 | 11篇 |
1977年 | 17篇 |
1976年 | 11篇 |
1975年 | 11篇 |
1974年 | 7篇 |
排序方式: 共有2441条查询结果,搜索用时 31 毫秒
1.
Nitsa Buaron Antonella Mangraviti Francesco Volpin Ann Liu Mariangela Pedone Eric Sankey Dina Aranovich Itay Adar Fausto J. Rodriguez Abraham Nyska Riki Goldbart Tamar Traitel Henry Brem Betty Tyler Joseph Kost 《Advanced functional materials》2021,31(44):2100643
Treating neuroinflammation-related injuries and disorders through manipulation of neuroinflammation functions is being heralded as a new therapeutic strategy. In this study, a novel pectic galactan (PG) polysaccharide based gene therapy approach is developed for targeting reactive gliosis in neuroinflammation. Galectin-3 (Gal-3) is a cell protein with a high affinity to β-galactoside sugars and is highly expressed in reactive gliosis. Since PG carries galactans, it can target reactive gliosis via specific carbohydrate interaction between galactan and Gal-3 on the cell membrane, and therefore can be utilized as a carrier for delivering genes to these cells. The carrier is synthesized by modifying quaternary ammonium groups on the PG. The resulting quaternized PG (QPG) is found to form complexes with plasmid DNA with a mean diameter of 100 nm and have the characteristics required for targeted gene therapy. The complexes efficiently condense large amounts of plasmid per particle and successfully bind to Gal-3. The in vivo study shows that the complexes are biocompatible and safe for administration and can selectively transfect reactive glial cells of an induced cortical lesion. The results confirm that this PG-based delivery system is a promising platform for targeting Gal-3 overexpressing neuroinflammation cells for treating neuroinflammation-related injuries and neurodegenerative diseases. 相似文献
2.
3.
A historical review of licensing among industrial/organizational (I/O) psychologists demonstrates that the American Psychological Association (APA) policy on such licensing is inconsistent. Arguments for and against licensure for this group are presented. Job analysis and APA data are drawn upon to show that few I/O activities may pose the personal risk that would seem to require the protection of a license. Alternatives are discussed for changes in present APA policy and state licensing requirements. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
5.
Due to their small size, mammalian oocytes and embryos pose unique problems during preparation for transmission electron microscopy. This paper outlines a method which combines protein embedding with centrifugation to locate the specimens on the face of a Beem capsule mould. This method facilitates both the processing of oocytes with minimal loss and rapid location of the specimens within the block for simultaneous sectioning, staining and examination. 相似文献
6.
Reviews available research on the meaning and measurement of denial and strategies for treating maladaptive denial, with special reference to its occurrence in traumatic head injuries. Questionnaire or interview measures, rather than behavioral indices, are used to assess denial. Denial may be manifested with respect to past, present, or future status; and it may have both positive and negative consequences for coping, motivation, and rehabilitation. Where denial limits a patient's functioning or recovery, several treatment strategies are possible. Intervention should involve a balance between supportive and confrontational elements, with a focus on behaviors rather than verbalizations. Computer feedback, videotaping, focused group therapy, and supervised activities are possible interventions for confronting maladaptive forms of denial. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Ann R Thryft 《电子设计技术》2008,15(7):78-78,80,82,84,86
数年来,具有10Gbps速度的下一代以太网一直处于即将成为主流的状况。一段时间以来,网络的某些区域已在使用光学技术,并且随着流量的增加,对10GbE数据速率的需求正在增长。但是,需要一种比上一代以太网复杂许多的技术,用于在100m长的铜缆上运行10GbE。这一要求导致了昂贵的MAC(媒体访问控制器)和交换芯片,以及昂贵而又不方便的PHY层接口芯片,由此限制了快速LAN用于那些覆盖数据中心内较短距离的高性能应用。 相似文献
8.
9.
10.
To examine the separate effects of viscosity and sweetness on astringency, aqueous solutions of grape seed tannin (GST) were thickened with carboxymethyl cellulose (CMC) from 2 to 45 cP (experiment 1) or sweetened with 0 to 1.8 g/L aspartame (experiment 2). Trained subjects continuously rated astringency and bitterness in duplicate. Subjects were categorized by the salivary flow induced by citric acid and ability to taste n-propyl thiouracil (PROP). In experiment 1, maximum intensity and total duration of astringency were significantly decreased as viscosity rose, although time to maximum intensity of astringency was not affected. Maximum intensity and total duration of bitterness were not significantly affected by increasing viscosity; however, the onset of bitterness was significantly delayed. In experiment 2, increasing sweetness had no affect on any astringency parameter, although maximum intensity of bitterness was significantly decreased. Neither PROP nor salivary flow-status had any effect on perception of bitterness or astringency in either experiment. 相似文献