全文获取类型
收费全文 | 1145篇 |
免费 | 62篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 13篇 |
综合类 | 1篇 |
化学工业 | 414篇 |
金属工艺 | 6篇 |
机械仪表 | 27篇 |
建筑科学 | 53篇 |
矿业工程 | 1篇 |
能源动力 | 43篇 |
轻工业 | 132篇 |
水利工程 | 6篇 |
石油天然气 | 1篇 |
无线电 | 76篇 |
一般工业技术 | 198篇 |
冶金工业 | 41篇 |
原子能技术 | 18篇 |
自动化技术 | 180篇 |
出版年
2024年 | 2篇 |
2023年 | 14篇 |
2022年 | 55篇 |
2021年 | 60篇 |
2020年 | 32篇 |
2019年 | 25篇 |
2018年 | 30篇 |
2017年 | 35篇 |
2016年 | 49篇 |
2015年 | 34篇 |
2014年 | 40篇 |
2013年 | 81篇 |
2012年 | 76篇 |
2011年 | 111篇 |
2010年 | 65篇 |
2009年 | 78篇 |
2008年 | 64篇 |
2007年 | 47篇 |
2006年 | 39篇 |
2005年 | 36篇 |
2004年 | 32篇 |
2003年 | 30篇 |
2002年 | 36篇 |
2001年 | 16篇 |
2000年 | 12篇 |
1999年 | 12篇 |
1998年 | 15篇 |
1997年 | 6篇 |
1996年 | 10篇 |
1995年 | 12篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 9篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1928年 | 2篇 |
1901年 | 1篇 |
排序方式: 共有1210条查询结果,搜索用时 15 毫秒
101.
Marzia Perluigi Rukhsana Sultana Giovanna Cenini Fabio Di Domenico Maurizio Memo William M. Pierce Raffaella Coccia D. Allan Butterfield 《Proteomics. Clinical applications》2009,3(6):682-693
Numerous studies have shown that neuronal lipids are highly susceptible to oxidative stress including in those brain areas directly involved in the neurodegenerative process of Alzheimer's disease (AD). Lipid peroxidation directly damages membranes and also generates a number of secondary biologically active products (toxic aldehydes)that are capable of easily attacking lipids, proteins, and DNA. Accumulating evidence has demonstrated regionally increased brain lipid peroxidation in patients with AD; however, extensive studies on specific targets of lipid peroxidation‐induced damage are still missing. The present study represents a further step in understanding the relationship between oxidative modification of protein and neuronal death associated with AD. We used a proteomics approach to determine specific targets of lipid peroxidation in AD brain, both in hippocampus and inferior parietal lobule, by coupling immunochemical detection of 4‐hydroxynonenal‐bound proteins with 2‐D polyacrylamide gel electrophoresis and MS analysis. We identified 4‐hydroxynonenal‐bound proteins in the hippocampus and inferior parietal lobule brain regions of subjects with AD. The identified proteins play different biological functions including energy metabolism, antioxidant system, and structural proteins, thus impairing multiple molecular pathways. Our results provide further evidence for the role of lipid peroxidation in the pathogenesis of AD. 相似文献
102.
Contribution of irrigation and cultivars to volatile profile and sensory attributes of selected virgin olive oils produced in Tunisia 总被引:1,自引:0,他引:1
103.
104.
Francesco Di Girolamo Andrea Masotti Isabella Lante Margherita Scapaticci Cosima Damiana Calvano Carlo Zambonin Maurizio Muraca Lorenza Putignani 《International journal of molecular sciences》2015,16(9):20896-20912
Extra virgin olive oil (EVOO) with its nutraceutical characteristics substantially contributes as a major nutrient to the health benefit of the Mediterranean diet. Unfortunately, the adulteration of EVOO with less expensive oils (e.g., peanut and corn oils), has become one of the biggest source of agricultural fraud in the European Union, with important health implications for consumers, mainly due to the introduction of seed oil-derived allergens causing, especially in children, severe food allergy phenomena. In this regard, revealing adulterations of EVOO is of fundamental importance for health care and prevention reasons, especially in children. To this aim, effective analytical methods to assess EVOO purity are necessary. Here, we propose a simple, rapid, robust and very sensitive method for non-specialized mass spectrometric laboratory, based on the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) coupled to unsupervised hierarchical clustering (UHC), principal component (PCA) and Pearson’s correlation analyses, to reveal corn oil (CO) adulterations in EVOO at very low levels (down to 0.5%). 相似文献
105.
Stefano Giovagnoli Aurelie Schoubben Maurizio Ricci 《Drug development and industrial pharmacy》2017,43(3):347-363
Not all of the issues impacting the success of tuberculosis (TB) treatment arise from pathogen-related disease characteristics. Nowadays, there is an increasing awareness that antibiotic treatment is not the only answer to the TB problem, promoting the search for alternative administration strategies and host-directed therapies. Among all the administration routes, being the lungs the main TB focus, inhalation is conceptually a logical solution to enhance treatment effectiveness and compliance. Nevertheless, research efforts and funding are almost entirely conveyed to conventional approaches. This review will critically evaluate the reasons constraining research in this field, providing some future perspectives. The most recent advances in inhalation approaches for TB will be discussed, either at the preclinical or clinical phase, illustrating the risk of failure and chances of success. 相似文献
106.
107.
108.
Functionalized carbon nanotubes are non-cytotoxic and preserve the functionality of primary immune cells 总被引:1,自引:0,他引:1
Dumortier H Lacotte S Pastorin G Marega R Wu W Bonifazi D Briand JP Prato M Muller S Bianco A 《Nano letters》2006,6(7):1522-1528
Carbon nanotubes are emerging as innovative tools in nanobiotechnology. However, their toxic effects on environment and health have become an issue of strong concern. In the present study, we address the impact of functionalized carbon nanotubes (f-CNTs) on cells of the immune system. We have prepared two types of f-CNTs, following the 1,3-dipolar cycloaddition reaction (f-CNTs 1 and 2) and the oxidation/amidation treatment (f-CNTs 3 and 4), respectively. We have found that both types of f-CNTs are uptaken by B and T lymphocytes as well as macrophages in vitro, without affecting cell viability. Subsequently, the functionality of the different cells was analyzed carefully. We discovered that f-CNT 1, which is highly water soluble, did not influence the functional activity of immunoregulatory cells. f-CNT 3, which instead possesses reduced solubility and forms mainly stable water suspensions, preserved lymphocytes' functionality while provoking secretion of proinflammatory cytokines by macrophages. 相似文献
109.
Bonifazi D Nacci C Marega R Campidelli S Ceballos G Modesti S Meneghetti M Prato M 《Nano letters》2006,6(7):1408-1414
Understanding and controlling the chemical reactivity of carbon nanotubes (CNTs) is a fundamental requisite to prepare novel nanoscopic structures with practical uses in materials applications. Here, we present a comprehensive microscopic and spectroscopic characterization of carbon nanotubes which have been chemically modified. Specifically, scanning tunneling microscopy (STM) investigations of short-oxidized single-walled carbon nanotubes (SWNTs) functionalized with aliphatic chains via amide reaction reveal the presence of bright lumps both on the sidewalls and at the tips. The functionalization pattern is consistent with the oxidation reaction which mainly occurs at the nanotube tips. Thermogravimetric analysis (TGA), steady-state electronic absorption (UV-vis-NIR), and Raman spectroscopic studies confirm the STM observations. 相似文献
110.
This paper focuses on the problem of key‐frames coding and proposes a new promising approach based on the use of fractals. The summary, made of a set of key‐frames selected from a full‐length video sequence, is coded by using a 3D fractal scheme. This allows the video presentation tool to expand the video sequence in a “natural” way by using the property of the fractals to reproduce the signal at several resolutions. This feature represents an important novelty of this work with respect to the alternative approaches, which mainly focus on the compression ratio without taking into account the presentation aspect of the video summary. In devising the coding scheme, we have taken care of the computational complexity inherent in fractal coding. Accordingly, the key‐frames are first wavelet transformed, and the fractal coding is then applied to each subband to reduce the search range. Experimental results show the effectiveness of the proposed approach. 相似文献