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991.
de Moura SA de Sousa JM Lima DF Negreiros AN Silva Fde V da Costa LJ 《Gerodontology》2007,24(3):173-176
Objective: The aim of the present study was to analyse the characteristics of salivary production and its composition in individuals with burning mouth syndrome (BMS). Study Design: Salivary flow rate, concentrations of potassium, iron, chloride, thiocyanate, magnesium, calcium, phosphorus, glucose, total protein and urea, as well as the expression profile of salivary proteins were analysed by SDS‐PAGE. Results: The mean salivary flow rate among control patients was lower than that of BMS patients. Chloride, phosphorus and potassium levels were elevated in patients with BMS (p = 0.041, 0.001 and 0.034, respectively). Total salivary protein concentration was reduced in individuals with BMS (p = 0.223). Analysis of the expression of salivary proteins by Coomassie blue SDS‐PAGE revealed a lower expression of low molecular weight proteins in individuals with BMS compared to healthy controls. Conclusions: These results indicate that the identification and characterisation of low molecular weight salivary proteins in BMS may be important in understanding BMS pathogenesis, thus contributing to its diagnosis and treatment. 相似文献
992.
993.
Serotonin(4) (5-HT(4)) receptor agonists are putative antidepressants with a rapid onset of action 总被引:6,自引:0,他引:6
Lucas G Rymar VV Du J Mnie-Filali O Bisgaard C Manta S Lambas-Senas L Wiborg O Haddjeri N Piñeyro G Sadikot AF Debonnel G 《Neuron》2007,55(5):712-725
Current antidepressants are clinically effective only after several weeks of administration. Here, we show that serotonin(4) (5-HT(4)) agonists reduce immobility in the forced swimming test, displaying an antidepressant potential. Moreover, a 3 day regimen with such compounds modifies rat brain parameters considered to be key markers of antidepressant action, but that are observed only after 2-3 week treatments with classical molecules: desensitization of 5-HT(1A) autoreceptors, increased tonus on hippocampal postsynaptic 5-HT(1A) receptors, and enhanced phosphorylation of the CREB protein and neurogenesis in the hippocampus. In contrast, a 3 day treatment with the SSRI citalopram remains devoid of any effect on these parameters. Finally, a 3 day regimen with the 5-HT(4) agonist RS 67333 was sufficient to reduce both the hyperlocomotion induced by olfactory bulbectomy and the diminution of sucrose intake consecutive to a chronic mild stress. These findings point out 5-HT(4) receptor agonists as a putative class of antidepressants with a rapid onset of action. 相似文献
994.
995.
Yuan L Rodrigues PH Bélanger M Dunn W Progulske-Fox A 《FEMS immunology and medical microbiology》2007,51(2):388-398
ClpB, a component of stress response in microorganisms, serves as a chaperone, preventing protein aggregation and assisting in the refolding of denatured proteins. A clpB mutant of Porphyromonas gingivalis W83 demonstrated increased sensitivity to heat stress, but not to hydrogen peroxide and extreme pHs. In KB cells, human coronary artery endothelial (HCAE) cells and gingival epithelial cells, the clpB mutant exhibited significantly decreased invasion suggesting that the ClpB protein is involved in cellular invasion. Transmission electron microscopic analysis showed that the clpB mutant was more susceptible to intracellular killing than the wild-type strain in HCAE cells. The global genetic profile of the clpB mutant showed that 136 genes belonging to several different cellular function groups were differentially regulated, suggesting that ClpB is ultimately involved in the expression of multiple P. gingivalis genes. A competition assay in which a mixture of wild-type W83 and the clpB mutant were injected into mice demonstrated that the clpB mutant did not survive as well as the wild type. Additionally, mice treated with the clpB mutant alone survived significantly better than those treated with the wild-type strain. Collectively, these data suggest that ClpB, either directly or indirectly, plays an important role in P. gingivalis virulence. 相似文献
996.
do Nascimento AM Costa FC Thiemann OH de Oliveira DC 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(5-6):353-356
The dichloromethane extract of Calea uniflora afforded a mixture of two novel chromanones, uniflorol-A (1) and uniflorol-B (2), and one known chromanone, 2,2-dimethyl-6-(1-hydroxyethyl)-chroman-4-one (3). The structures of these compounds were determined by spectroscopic methods. Biological activity of the compounds against Leishmania major promastigotes was evaluated. Mixture of the novel chromanones 1 and 2 showed significant growth inhibition of the parasite in the micrograms per milliliter range. 相似文献
997.
Andreas Kicherer Stefan Schaltegger Heinrich Tschochohei Beatriz Ferreira Pozo 《The International Journal of Life Cycle Assessment》2007,12(7):537-543
Goal, Scope and Background The eco-efficiency analysis and portfolio is a powerful decision support tool for various strategic and marketing issues.
Since its original academic development, the approach has been refined during the last decade and applied to a multitude of
projects. BASF, as possibly the most prominent company using and developing this tool, has applied the eco-efficiency approach
to more than 300 projects in the last 7 years. One of the greatest difficulties is to cover both dimensions of eco-efficiency
(costs or value added and environmental impact) in a comparable manner. This is particularly a challenge for the eco-efficiency
analyses of products.
Methods In this publication, an important approach and field of application dealing with product decisions based on the combination
of Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) is described in detail. Special emphasis is put on the quantitative
assessment of the relation of costs and environmental impacts. In conventional LCA an assessment of environmental impact categories
is often made by normalization with inhabitant equivalents. This is necessary to be able to compare the different environmental
impact categories, because of each different unit. For the proposed eco-efficiency analysis, the costs of products or processes
are also normalized with adapted gross domestic product figures.
Results and Discussion The ratio between normalized environmental impact categories and normalized costs (RE,C) is used for the graphical presentation of the results in an eco-efficiency portfolio. For the interpretation of the results
of an eco-efficiency analysis, it is important to distinguish ratios RE,C which are higher than one from ratios lower than one. In the first case, the environmental impact is higher than the cost
impact, while the inverse is true in the second case. This is very important for defining which kind of improvement is needed
and defining strategic management decisions. The paper shows a statistical evaluation of the RE,C factor based on the results of different eco-efficiency analyses made by BASF. For industries based on large material flows
(e.g. chemicals, steel, metals, agriculture), the RE,C factor is typically higher than one.
Conclusions and Recommendations This contribution shows that LCC and LCA may be combined in a way that they mirror the concept of eco-efficiency. LCAs that
do not consider LCC may be of very limited use for company management. For that very reason, corporations should install a
data management system that ensures equal information on both sides of the eco-efficiency coin. 相似文献
998.
Life cycle assessment of a multi-material car component 总被引:1,自引:1,他引:0
Catarina Ribeiro José V. Ferreira Paulo Partidário 《The International Journal of Life Cycle Assessment》2007,12(5):336-345
Background, Aims and Scope In recent years, the automotive industry has been experiencing an increasing concern with environmental requirements. A particular
focus is being given to light-weighting of cars, to reducing fuel consumption and to the use of different recycling materials.
Consequently, decisions on product design and development must involve economic and technological as well as environmental
considerations. In adequate conditions, the LCA methodology enables one to assist an effective integration of the environmental
considerations in the decision-making process [1]. In this paper, a multi-material car component which is part of the current
automotive brake system, has been modified by its original manufacturer. Such a modification included the use of a new multi-material
injection moulding process and the consumption of recyclable materials. The new and the current component were comparatively
assessed throughout their life cycles in order to evaluate their respective environmental impacts and, thus, to verify if
the new component offers a lower environmental load. The results described in this paper are part of the outcome of a broader
research project involving industrial companies, university, technological centres and research institutes based in Portugal,
Spain and Germany.
Main Features The car component under focus has four subcomponents whose base materials consist of steel and plastic. The LCA methodology
is used to evaluate two scenarios describing the new car component, on the one hand, and the reference scenario, which consists
of the existing car component, on the other. The former results from the selection of new subcomponents materials, aiming
to use a new production process together with a recycling strategy.
Results and Discussion The inventory analysis shows a lower energy consumption in the alternative scenario (4.2 MJ) compared to the reference scenario
(6.1 MJ). Most of that energy is still non-renewable, relating in particular to crude consumption in the car use phase and
in the production phase (transports and plastics production). The life cycle inventory analysis indicates also that the alternative
scenario has lower air emissions of CO2, CO, NOx, SOx, NM VOC and PM10, as well as lower solid wastes and water emissions of oils and BOD5. Otherwise, the water emissions of undissolved
substances and COD are higher for the alternative scenario. Most of the energy consumed and the air pollutants inventoried
occur as a consequence of the use phase. Otherwise, for most of the life cycle water emissions inventoried and solid wastes,
the production phase is the major contributor. The impact assessment, performed with the CML method, allows one to conclude
that the alternative scenario exhibits lower results in all the impact categories. Both scenarios have similar environmental
profiles, being: (i) the use phase, the major contributor for the abiotic depletion, global warming, photochemical oxidation,
acidification and eutrophication; and (ii) the production phase, the main contributor for ozone depletion, human toxicity,
fresh water aquatic ecotoxicity, marine aquatic ecotoxicity and terrestrial ecotoxicity. The sensitivity analysis, with respect
to the fuel consumption reduction value, the impact assessment method and the final disposal scenario, performed in this study
allows one to confirm, as a main conclusion, that the alternative scenario is environmentally preferable to the reference
scenario.
Conclusion The results obtained through the application of the LCA methodology enable one to conclude that the alternative component
has a lower environmental load than the reference component.
Recommendations and Perspectives Considering that the time required for the inventory data collection is a critical issue in LCA practise, the insights provided
by this particular case study are likely to be useful to product developers in the car component manufacturing industry, particularly
to brake system manufacturers supporting the environmental design within the sector. 相似文献
999.
1000.
Bruce Boghosian Peter Coveney Suchuan Dong Lucas Finn Shantenu Jha George Karniadakis Nicholas Karonis 《Cluster computing》2007,10(3):351-364
In response to a joint call from US’s NSF and UK’s EPSRC for applications that aim to utilize the combined computational resources
of the US and UK, three computational science groups from UCL, Tufts and Brown Universities teamed up with a middleware team
from NIU/Argonne to meet the challenge. Although the groups had three distinct codes and aims, the projects had the underlying
common feature that they were comprised of large-scale distributed applications which required high-end networking and advanced
middleware in order to be effectively deployed. For example, cross-site runs were found to be a very effective strategy to
overcome the limitations of a single resource.
The seamless federation of a grid-of-grids remains difficult. Even if interoperability at the middleware and software stack
levels were to exist, it would not guarantee that the federated grids can be utilized for large scale distributed applications.
There are important additional requirements for example, compatible and consistent usage policy, automated advanced reservations
and most important of all co-scheduling. This paper outlines the scientific motivation and describes why distributed resources
are critical for all three projects. It documents the challenges encountered in using a grid-of-grids and some of the solutions
devised in response. 相似文献