全文获取类型
收费全文 | 1270篇 |
免费 | 84篇 |
专业分类
电工技术 | 7篇 |
综合类 | 4篇 |
化学工业 | 443篇 |
金属工艺 | 12篇 |
机械仪表 | 22篇 |
建筑科学 | 53篇 |
能源动力 | 17篇 |
轻工业 | 163篇 |
水利工程 | 11篇 |
石油天然气 | 1篇 |
无线电 | 61篇 |
一般工业技术 | 209篇 |
冶金工业 | 213篇 |
自动化技术 | 138篇 |
出版年
2024年 | 1篇 |
2023年 | 23篇 |
2022年 | 71篇 |
2021年 | 93篇 |
2020年 | 45篇 |
2019年 | 45篇 |
2018年 | 35篇 |
2017年 | 42篇 |
2016年 | 36篇 |
2015年 | 51篇 |
2014年 | 38篇 |
2013年 | 70篇 |
2012年 | 80篇 |
2011年 | 101篇 |
2010年 | 75篇 |
2009年 | 67篇 |
2008年 | 82篇 |
2007年 | 69篇 |
2006年 | 55篇 |
2005年 | 34篇 |
2004年 | 39篇 |
2003年 | 35篇 |
2002年 | 26篇 |
2001年 | 23篇 |
2000年 | 16篇 |
1999年 | 11篇 |
1998年 | 18篇 |
1997年 | 12篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 1篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 7篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有1354条查询结果,搜索用时 0 毫秒
1.
Nicole Jacqueline Jensen Helena Zander Wodschow Malin Nilsson Jrgen Rungby 《International journal of molecular sciences》2020,21(22)
Under normal physiological conditions the brain primarily utilizes glucose for ATP generation. However, in situations where glucose is sparse, e.g., during prolonged fasting, ketone bodies become an important energy source for the brain. The brain’s utilization of ketones seems to depend mainly on the concentration in the blood, thus many dietary approaches such as ketogenic diets, ingestion of ketogenic medium-chain fatty acids or exogenous ketones, facilitate significant changes in the brain’s metabolism. Therefore, these approaches may ameliorate the energy crisis in neurodegenerative diseases, which are characterized by a deterioration of the brain’s glucose metabolism, providing a therapeutic advantage in these diseases. Most clinical studies examining the neuroprotective role of ketone bodies have been conducted in patients with Alzheimer’s disease, where brain imaging studies support the notion of enhancing brain energy metabolism with ketones. Likewise, a few studies show modest functional improvements in patients with Parkinson’s disease and cognitive benefits in patients with—or at risk of—Alzheimer’s disease after ketogenic interventions. Here, we summarize current knowledge on how ketogenic interventions support brain metabolism and discuss the therapeutic role of ketones in neurodegenerative disease, emphasizing clinical data. 相似文献
2.
3.
4.
5.
6.
7.
8.
Claudia Stewart Nicole Lum Robert Hill Robert Stephens Paul Rudnick Lynn Rassmussen 《Journal of The Association for Laboratory Automation》2003,8(2):64-65
Primer walking of cloned DNA is a standard research tool. It has been used in the past to determine the sequence of individual clones of interest. With the expansion of DNA sequencing capacity the need to be able to walk larger numbers of clones has become necessary. Our laboratory is a mid-sized genomics facility. In conjunction with the Advanced Biomedical Computing Center (ABCC) we have developed methods for automating the primer selection, DNA sequencing, contig assembly and sequence analysis for clones arrayed in microtiter format. This approach has allowed us to walk 475 clones (five microtiter plates) selected from a cDNA library. 相似文献
9.
Preexposing rats to the context facilitates subsequent contextual fear conditioning. This effect depends on the hippocampus (J. W. Rudy, R. M. Barrientos, & R. C. O'Reilly, 2002). The authors report that inactivating the basolateral region of the amygdala (BLA) by injecting muscimol, a GABAA agonist, before or after preexposure reduced this effect. In contrast, bilateral injections of anisomycin, a protein synthesis inhibitor, into BLA did not impair the consolidation of the context memory. However, when injected after fear conditioning, anisomycin impaired consolidation of both contextual and auditory-cue fear conditioning. Results are consistent with 2 ideas about the amygdala's contribution to memory: (a) It modulates memory formation in other regions of the brain, and (b) it is a storage site for cue-shock associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Ahluwalia Jasjit S.; Nollen Nicole; Kaur Harsohena; James Aimee S.; Mayo Matthew S.; Resnicow Ken 《Canadian Metallurgical Quarterly》2007,26(2):214
Objectives: Examine the effectiveness of an intervention to increase fruits and vegetables (FV) consumption among smokers. Design: Cluster-randomized trial of 20 public housing developments; 10 randomly assigned to an FV intervention and 10 to a smoking cessation intervention. Main outcome measures: Usual (past 7 days) and past 30 days change in daily FV intake at 8 weeks and 6 months postbaseline. Results: Greater increases were seen in the FV group. At Week 8 and Month 6, the FV group had consumed 1.58 (p = .001) and 0.78 (p = .04), respectively, more daily FV servings in the past 7 days than the cessation group. At the same time points, the FV group had consumed 3.61 (p = .01) and 3.93 (p = .01), respectively, more FV servings in the past 30 days than the cessation group. Completing more motivational interviewing sessions (p = .02) and trying more recipes (p = .02) led to significantly greater increases at Month 6 among FV participants. Conclusions: Motivational interviewing counseling and lifestyle modification through trying out healthy recipes may be effective in helping a high-risk population increase their FV intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献