全文获取类型
收费全文 | 2037篇 |
免费 | 50篇 |
国内免费 | 225篇 |
专业分类
电工技术 | 8篇 |
综合类 | 39篇 |
化学工业 | 288篇 |
金属工艺 | 188篇 |
机械仪表 | 31篇 |
建筑科学 | 58篇 |
矿业工程 | 1篇 |
能源动力 | 3篇 |
轻工业 | 333篇 |
水利工程 | 2篇 |
石油天然气 | 6篇 |
武器工业 | 2篇 |
无线电 | 70篇 |
一般工业技术 | 102篇 |
冶金工业 | 1033篇 |
原子能技术 | 20篇 |
自动化技术 | 128篇 |
出版年
2023年 | 26篇 |
2022年 | 109篇 |
2021年 | 115篇 |
2020年 | 68篇 |
2019年 | 84篇 |
2018年 | 58篇 |
2017年 | 64篇 |
2016年 | 36篇 |
2015年 | 40篇 |
2014年 | 73篇 |
2013年 | 74篇 |
2012年 | 50篇 |
2011年 | 96篇 |
2010年 | 97篇 |
2009年 | 89篇 |
2008年 | 87篇 |
2007年 | 101篇 |
2006年 | 95篇 |
2005年 | 140篇 |
2004年 | 118篇 |
2003年 | 67篇 |
2002年 | 85篇 |
2001年 | 56篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 12篇 |
1997年 | 11篇 |
1992年 | 16篇 |
1990年 | 14篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 13篇 |
1986年 | 19篇 |
1985年 | 13篇 |
1984年 | 15篇 |
1983年 | 14篇 |
1981年 | 14篇 |
1979年 | 13篇 |
1971年 | 13篇 |
1966年 | 20篇 |
1965年 | 15篇 |
1964年 | 11篇 |
1963年 | 17篇 |
1962年 | 11篇 |
1960年 | 9篇 |
1959年 | 14篇 |
1958年 | 18篇 |
1957年 | 16篇 |
1956年 | 9篇 |
1955年 | 22篇 |
排序方式: 共有2312条查询结果,搜索用时 0 毫秒
51.
52.
Stefan Weinschenk Carsten Weiss Justus Benrath Volker von Baehr Thomas Strowitzki Manuel Feißt 《International journal of molecular sciences》2022,23(6)
Background. Local anesthetics (LAs) have potent anti-inflammatory properties. Inflammatory down-regulation is crucial in diseases with overactive immune reactions, such as acute respiratory distress syndrome (ARDS) and chronic inflammation. We investigated the influence of four LAs, procaine, lidocaine, mepivacaine, and bupivacaine, on the reduction of tumor necrosis factor-alpha (TNF-α) secretion in lipopolysaccharide (LPS)-activated human leucocytes. Methods. Blood samples of 28 individuals were stimulated with LPS. The reduction of TNF-α production by each of the four LAs added (0.5 mg/mL) was measured and correlated with biometric variables. A response was defined as reduction to <85% of initial levels. Results. All four LAs down-regulated the TNF-α secretion in 44–61%: Bupivacaine (44.4%), lidocaine (61.5%), mepivacaine (44.4%), and procaine (50% of the individuals, “responders”). The TNF-α secretion was reduced to 67.4, 68.0, 63.6, and 67.1% of the initial values in responders. The effects in both patients and healthy persons were the same. Interindividual responses to LAs were not correlated with the duration or type of complaints, basal TNF-α serum level, sex, BMI, or age of responders. Conclusions. Four clinically relevant LAs (amid-LA and ester-LA) attenuate the inflammatory response provoked by LPS. They are potential candidates for drug repositioning in treating overactive immune reactions and chronic inflammation. 相似文献
53.
Computer‐Interpretable Guidelines (CIGs) are the dominant medium for the delivery of clinical decision support, given the evidence‐based nature of their source material. Therefore, these machine‐readable versions have the ability to improve practitioner performance and conformance to standards, with availability at the point and time of care. The formalisation of Clinical Practice Guideline knowledge in a machine‐readable format is a crucial task to make it suitable for the integration in Clinical Decision Support Systems. However, the current tools for this purpose reveal shortcomings with respect to their ease of use and the support offered during CIG acquisition and editing. In this work, we characterise the current landscape of CIG acquisition tools based on the properties of guideline visualisation, organisation, simplicity, automation, manipulation of knowledge elements, and guideline storage and dissemination. Additionally, we describe the CompGuide Editor, a tool for the acquisition of CIGs in the CompGuide model for Clinical Practice Guidelines that also allows the editing of previously encoded guidelines. The Editor guides the users throughout the process of guideline encoding and does not require proficiency in any programming language. The features of the CIG encoding process are revealed through a comparison with already established tools for CIG acquisition. 相似文献
54.
55.
Wahab Ali Khan Masood Sadiq Butt Imran Pasha Muhammad Saeed Iqra Yasmin Maratab Ali Muhammad Azam Muhammad Shahroz Khan 《Journal of texture studies》2020,51(6):955-967
Vitamin D lost its functionality during processing and storage, thus, encapsulation with proteins is desirable to preserve bioactivity. The aim of the current study was to develop encapsulated vitamin D fortified mayonnaise (VDFM) using whey protein isolates (WPI) and soy protein isolates (SPI) as encapsulating materials in three different formulations, that is, 10% WPI, 10% SPI, and 5/5% WPI/SPI. Increased shear stress decreased the apparent viscosity along with significant effects on the loss modulus of VDFM. WPI encapsulates showed better results as compared to SPI. WPI based VDFM (M1) depicted the best results in terms of size and dispersion uniformity of oil droplets. Hue angle and total change differed significantly among treatments. The highest value for overall acceptability was acquired by M3 (5:5%WPI:SPI-encapsulates) thus proceed for in vivo trials. Serum vitamin D level was significantly higher in the encapsulated VDFM rat group (58.14 ± 6.29 nmol/L) than the control (37.80 ± 4.98 nmol/L). Conclusively, WPI and SPI encapsulates have the potential to improve the stability and bioavailability of vitamin D. 相似文献
56.
57.
Ayşegül Güven 《中国工程学刊》2019,42(4):357-365
Diagnostic efforts to identify alcoholism are frequently subjective; however, recent technological advances have allowed the automated assessment of objective signals. To improve the performance of the automated classification of patients with alcohol dependence (AD) and controls, we analyzed features of event-related potentials (ERPs) in 72 subjects with AD and 42 controls while the subjects underwent three different visual oddball tasks. In addition to such commonly used morphological features (MFs) as time-domain amplitude and latency components as well as discrete wavelet transform coefficient entropies (WEs), we analyzed Hu moment invariants (HMIs) in this study. Smaller P3 and P2 amplitudes, longer latencies, lower WE values, and lower HMI values were observed for AD subjects relative to those observed for controls. We used a Naïve Bayes algorithm to compare classification accuracies among MFs, WEs, HMIs, combinations of MFs/WEs, and combinations of all three characteristics. We found that HMIs improved the classification accuracy by 17%. Our findings demonstrated that a combined feature analysis of ERPs obtained during a visual oddball task can be a useful and discriminative tool for diagnostic purposes in alcoholism and that HMIs show promise for improving the objective diagnosis of alcoholism and similar diseases. 相似文献
58.
Annurca (Malus pumila Miller cv. Annurca) apple as a functional food for the contribution to a healthy balance of plasma cholesterol levels: results of a randomized clinical trial 下载免费PDF全文
59.
60.
Irene Zorraquín Eva Sánchez-Hernández Begoña Ayuda-Durán Mariana Silva Ana M González-Paramás Celestino Santos-Buelga Maria V Moreno-Arribas Begoña Bartolomé 《Journal of the science of food and agriculture》2020,100(10):3789-3802
Interactions between polyphenols and gut microbiota are indeed a major issue of current interest in food science research. Knowledge in this subject is progressing as the experimental procedures and analysis techniques do. The aim of this article is to critically review the more leading-edge approaches that have been applied so far in the study of the interactions between grape/wine polyphenols and gut microbiota. This is the case of in vitro dynamic gastrointestinal simulation models that try to mitigate the limitations of simple static models (batch culture fermentations). More complex approaches include the experimentation with animals (mice, rats, pigs, lambs and chicks) and nutritional intervention studies in humans. Main advantages and limitations as well as the most relevant findings achieved by each approach in the study of how grape/wine polyphenols can modulate the composition and/or functionality of gut microbiota, are detailed. Also, common findings obtained by the three approaches (in vitro, animal models and human nutritional interventions) such as the fact that the Firmicutes/Bacteroidetes ratio tends to decrease after the feed/intake/consumption of grape/wine polyphenols are highlighted. Additionally, a nematode (Caenorhabditis elegans) model, previously used for investigating the mechanisms of processes such as aging, neurodegeneration, oxidative stress and inflammation, is presented as an emerging approach for the study of polyphenols interacting gut microbiota. © 2020 Society of Chemical Industry 相似文献