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161.
Hanan Samet 《Computer Languages, Systems and Structures》1979,4(3-4):187-198
Programming languages which use dynamic identification for free variables (i.e., non-local references) are generally implemented with a deep or shallow binding variable access strategy. In this paper, variable access through the binding environment is assumed to be desirable. Given this assumption, it is demonstrated that the act of assigning values to variables may yield unexpected results for some of the binding strategies when functional arguments and results are used. A number of variations of deep and shallow binding strategies are examined along with the modifications necessary to implement the assignment operation in the expected manner. 相似文献
162.
163.
T Wang L Wang L Moreno-Vinasco GD Lang JH Siegler B Mathew PV Usatyuk JM Samet AS Geyh PN Breysse V Natarajan JG Garcia 《Particle and fibre toxicology》2012,9(1):35
ABSTRACT: BACKGROUND: : Exposure to particulate matter (PM) is a significant risk factor for increased cardiopulmonary morbidity and mortality. The mechanism of PM-mediated pathophysiology remains unknown. However, PM is proinflammatory to the endothelium and increases vascular permeability in vitro and in vivo via ROS generation. OBJECTIVES: We explored the role of tight junction proteins as targets for PM-induced loss of lung endothelial cell (EC) barrier integrity and enhanced cardiopulmonary dysfunction. METHOD: S: Changes in human lung EC monolayer permeability were assessed by Transendothelial Electrical Resistance (TER) in response to PM challenge (collected from Ft. McHenry Tunnel, Baltimore, MD, particle size >0.1 um). Biochemical assessment of ROS generation and Ca2+ mobilization were also measured. RESULTS: : PM exposure induced tight junction protein ZO-1 relocation from the cell periphery, which was accompanied by significant reductions in ZO-1 protein levels but not in adherens junction proteins (VE-cadherin and beta-catenin). N-acetyl-cysteine (NAC, 5mM) reduced PM-induced ROS generation in ECs, which further prevented TER decreases and atteneuated ZO-1 degradation. PM also mediated intracellular calcium mobilization via the transient receptor potential cation channel M2 (TRPM2), in a ROS-dependent manner with subsequent activation of the Ca2+-dependent protease calpain. PM-activated calpain is responsible for ZO-1 degradation and EC barrier disruption. Overexpression of ZO-1 attenuated PM-induced endothelial barrier disruption and vascular hyperpermeability in vivo and in vitro. CONCLUSIONS: : These results demonstrate that PM induces marked increases in vascular permeability via ROS-mediated calcium leakage via activated TRPM2, and via ZO-1 degradation by activated calpain. These findings support a novel mechanism for PM-induced lung damage and adverse cardiovascular outcomes. 相似文献
164.
Smoking cessation in China: findings from the 1996 national prevalence survey 总被引:3,自引:0,他引:3
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OBJECTIVES: To describe patterns of smoking and smoking cessation in China within the context of the stages of change model, using data from the 1996 national prevalence survey. DESIGN: A cross sectional survey was carried out using the 145 preselected disease surveillance points, which provide a representative sample for the entire country. A standardised questionnaire on smoking was interviewer administered. SETTING: The country of China. SUBJECTS: 122,220 people aged 15-69 years. MAINTENANCE MEASURES: Smoking cessation patterns, as defined by smoking status (current or former) and stage of change (precontemplation, contemplation, and action). RESULTS: The sample included 45,995 ever smokers of whom 4336 had quit. About 72% of current smokers reported not intending to give up their smoking behaviour, and about 16% of current smokers said they intended to do so, but have not taken any action. Of all ever smokers, the percentage of former smokers was 9.5%, and 12% of current smokers had quit at least once, but relapsed by the time of the survey. The patterns were similar in men and women with regard to the stated intent to quit. Among males, the percentage of former smokers increased with age but the percentage intending to quit was constant at about 15% across age strata. The most common reason for quitting was illness. Participants with a university education were more likely to have made an attempt to quit. CONCLUSIONS: The percentage of smokers contemplating quitting was low in China in 1996. The study shows that smokers in China must be mobilised to contemplate quitting and then to take action. 相似文献
165.
166.
Maja Kosecka-Strojek Mariola Wolska-Gbarzewska Adrianna Podbielska-Kubera Alfred Samet Beata Krawczyk Jacek Midzobrodzki Micha Michalik 《International journal of molecular sciences》2022,23(12)
Staphylococcus lugdunensis is an opportunistic pathogen found in the healthy human skin microbiome bacterial community that is able to cause infections of diverse localization, manifestation, and course, including laryngological infections, such as necrotizing sinusitis. Chronic maxillary sinusitis is a disease present in up to one third of European and American populations, and its etiology is not fully described. Within this study, we aimed to characterize 18 S. lugdunensis strains recovered from maxillary sinuses and evaluate them as etiological agents of chronic disease. We performed MLST analysis, the complex analysis of both phenotypic and genetic virulence factors, antibiotic susceptibility profiles, and biofilm formation assay for the detection of biofilm-associated genes. Altogether, S. lugdunensis strains were clustered into eight different STs, and we demonstrated several virulence factors associated with the chronic disease. All tested strains were able to produce biofilm in vitro with numerous strains with a very strong ability, and overall, they were mostly susceptible to antibiotics, although we found resistance to fosfomycin, erythromycin, and clindamycin in several strains. We believe that further in-depth analysis of S. lugdunensis strains from different niches, including the nasal one, should be performed in the future in order to reduce infection rate and broaden the knowledge about this opportunistic pathogen that is gaining attention. 相似文献
167.
Chaker Essid M. Bassem Ben Salah Abdelaziz Samet 《International Journal of Numerical Modelling》2016,29(4):763-772
In this paper, a new hybrid method formulation to resolve the mixed potential integral equation in an efficient and a fast approach, which is based on a simultaneous formulation in both spatial and spectral domains, is proposed. The entries of the method of moments matrix are then given by the sum of two integrals. The first one is expressed in the spatial domain. This part is analytically evaluated after a development in Taylor series of the exponential terms in the function to integrate. The integrals expressed in the spectral domain have a finite range, and they are calculated using numerical integration. Then the convergence problem is avoided in this approach. A good agreement between the simulated and measured results has been achieved. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
168.
Daniil A. Rusanov Samah Mutasim Alfadul Ekaterina Yu. Portnyagina Dr. Eugenia A. Silyanova Nikita A. Kuznetsov Kirill E. Podpovetny Prof. Dr. Alexander V. Samet Prof. Dr. Victor V. Semenov Dr. Maria V. Babak 《Chembiochem : a European journal of chemical biology》2023,24(11):e202300161
Since the discovery of anticancer properties of a naturally occurring hexacyclic marine alkaloid Lamellarin D, the attempts have been made to prepare its synthetic analogues and elucidate the effects of each structural component on their activity profile. While F-ring-free, A-ring-free and B-ring-open lamellarins are known, E-ring-free analogues have never been investigated. In this work, we developed a facile and straightforward synthetic method toward E-ring-free lamellarin analogues based on the [3+2]-cycloaddition. For the first time, we prepared several pentacyclic lamellarin analogues without E-ring in their structure and assessed their cytotoxicity in a panel of cancer cell lines in comparison with several hexacyclic lamellarins. E-ring-free lamellarins were devoid of cytotoxicity due to their poor solubility in cellular environment. 相似文献