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1.
The Farwell and Donchin P300 speller interface is one of the most widely used brain-computer interface (BCI) paradigms for writing text. Recent studies have shown that the recognition accuracy of the P300 speller decreases significantly when eye movement is impaired. This report introduces the GeoSpell interface (Geometric Speller), which implements a stimulation framework for a P300-based BCI that has been optimised for operation in covert visual attention. We compared the Geospell with the P300 speller interface under overt attention conditions with regard to effectiveness, efficiency and user satisfaction. Ten healthy subjects participated in the study. The performance of the GeoSpell interface in covert attention was comparable with that of the P300 speller in overt attention. As expected, the effectiveness of the spelling decreased with the new interface in covert attention. The NASA task load index (TLX) for workload assessment did not differ significantly between the two modalities. PRACTITIONER SUMMARY: This study introduces and evaluates a gaze-independent, P300-based brain-computer interface, the efficacy and user satisfaction of which were comparable with those off the classical P300 speller. Despite a decrease in effectiveness due to the use of covert attention, the performance of the GeoSpell far exceeded the threshold of accuracy with regard to effective spelling.  相似文献   
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In this paper, we propose a system-level design methodology for the efficient exploration of the architectural parameters of the memory sub-systems, from the energy-delay joint perspective. The aim is to find the best configuration of the memory hierarchy without performing the exhaustive analysis of the parameters space. The target system architecture includes the processor, separated instruction and data caches, the main memory, and the system buses. To achieve a fast convergence toward the near-optimal configuration, the proposed methodology adopts an iterative local-search algorithm based on the sensitivity analysis of the cost function with respect to the tuning parameters of the memory sub-system architecture. The exploration strategy is based on the Energy-Delay Product (EDP) metric taking into consideration both performance and energy constraints. The effectiveness of the proposed methodology has been demonstrated through the design space exploration of a real-world case study: the optimization of the memory hierarchy of a MicroSPARC2-based system executing the set of Mediabench benchmarks for multimedia applications. Experimental results have shown an optimization speedup of 2 orders of magnitude with respect to the full search approach, while the near-optimal system-level configuration is characterized by a distance from the optimal full search configuration in the range of 2%.  相似文献   
4.
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption.  相似文献   
5.
The genus Thymus L. consists of many species of herbaceous perennials and sub-shrubs. A chemical characterisation of a collection of Thymus spp. originated from regions of Southern Italy was performed using GC and GC/MS. The accessions were collected from various natural habitats of the Basilicata and Puglia Regions and transferred into a new uniform environment. The study showed that amongst the 22 components of the oils the most recurrent ones were geraniol, thymol and α-terpinene followed by linalool, citral and trans-caryophillene. Cluster analysis led to the identification of two chemotypes: geraniol and thymol/α-terpinene; only a biotype remained separate from all others, probably because of its high content linalool (58%).  相似文献   
6.
Wahle KW  Caruso D  Ochoa JJ  Quiles JL 《Lipids》2004,39(12):1223-1231
Epidemiological studies show that populations consuming a predominantly plant-based Mediterranean-style diet exhibit lower incidences of chronic diseases than those eating a northern European or North American diet. This observation has been attributed to the greater consumption of fruits and vegetables and the lower consumption of animal products, particularly fat. Although total fat intake in Mediterranean populations can be higher than in other regions (ca. 40% of calories), the greater proportion is derived from olive oil and not animals. Increased olive oil consumption is implicated in a reduction in cardiovascular disease, rheumatoid arthritis, and, to a lesser extent, a variety of cancers. Olive oil intake also has been shown to modulate immune function, particularly the inflammatory processes associated with the immune system. Olive oil is a nonoxidative dietary component, and the attenuation of the in-flammatory process it elicits could explain its beneficial effects on disease risk since oxidative and inflammatory stresses appear to be underlying factors in the etiology of these diseases in man. The antioxidant effects of olive oil are probably due to a combination of its high oleic acid content (low oxidation potential compared with linoleic acid) and its content of a variety of plant antioxidants, particularly oleuropein, hydroxytyrosol, and tyrosol. It is also possible that the high oleic acid content and a proportionate reduction in linoleic acid intake would allow a greater conversion of α-linolenic acid (18∶3n−3) to longer-chain n−3 PUFA, which have characteristic health benefits. Adoption of a Mediterranean diet could confer health benefits in high-risk populations.  相似文献   
7.
The use of proper nanocarriers for dermal and transdermal delivery of anti-inflammatory drugs recently gained several attentions in the scientific community because they pass intact and accumulate payloads in the deepest layers of skin tissue. Ascorbyl palmitate-based vesicles (aspasomes) can be considered a promising nanocarrier for dermal and transdermal delivery due to their skin whitening properties and suitable delivery of payloads through the skin. The aim of this study was the synthesis of multidrug Idebenone/naproxen co-loaded aspasomes for the development of an effective anti-inflammatory nanomedicine. Aspasomes had suitable physicochemical properties and were safe in vivo if topically applied on human healthy volunteers. Idebenone/naproxen co-loaded aspasomes demonstrated an increased therapeutic efficacy of payloads compared to the commercially available Naprosyn® gel, with a rapid decrease of chemical-induced erythema on human volunteers. These promising results strongly suggested a potential application of Idebenone/naproxen multidrug aspasomes for the development of an effective skin anti-inflammatory therapy.  相似文献   
8.
Food packaging based on polymer nanomaterials   总被引:6,自引:0,他引:6  
Since its starting in the 19th century, modern food packaging has made great advances as results of global trends and consumer preferences. These advances are oriented to obtain improved food quality and safety. Moreover, with the move toward globalization, food packaging requires also longer shelf life, along with the monitoring of safety and quality based upon international standards. Nanotechnology can address all these requirements and extend and implement the principal packaging functions - containment, protection and preservation, marketing and communications. Applications of polymer nanotechnology in fact can provide new food packaging materials with improved mechanical, barrier and antimicrobial properties, together with nano-sensors for tracing and monitoring the condition of food during transport and storage.The latest innovations in food packaging, using improved, active and smart nanotechnology will be analyzed. It will be also discuss the limits to the development of the new polymer nanomaterials that have the potential to completely transform the food packaging industry.  相似文献   
9.
Quercetin shows interesting pharmacological effects, but its use in topical applications is limited by its low skin permeability and solubility. In this work, the synthesis of highly lipophilic quercetin esters with oleic, linoleic and linolenic acid useful as topical quercetin prodrugs is reported. Partial OH esterification is advisable to maintain the antioxidant activity of these compounds; tetraesters and triesters can be achieved by modulating the reaction conditions utilized for the total esterification of quercetin. The chemical structures of the esters were proven by spectroscopic techniques; quantum chemical NMR calculation were mandatory to unequivocally assign the free position in triesters. Finally, the antioxidant activity of all the synthesized compounds was determined by the 2,2-diphenyl-1-picryl-hydrazyl method and by 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) assay.  相似文献   
10.
Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria‐related deaths, has developed resistance against this drug. Twenty‐seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro‐2H‐quinolizine and 1,2,3,4,5,6‐hexahydro‐1,5‐methano‐8H‐pyrido[1,2‐a][1,5]diazocin‐8‐one, were synthesized and tested for activity against D‐10 (CQ‐susceptible) and W‐2 (CQ‐resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub‐micromolar IC50 values. Eleven compounds were found to be 2.7‐ to 13.4‐fold more potent than CQ against the W‐2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC‐1 and HepG2) along with easier synthetic accessibility. Replacement of the 4‐NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria.  相似文献   
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