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601.
One important problem when deploying interdomain path selection is advertising metrics that hold for a long period of time. In this paper we propose a method to aid interdomain path selection mechanisms in that sense. We present a means of computing a bound on the end‐to‐end delay of traversing a domain considering that the traffic varies within a given uncertainty set. This provides a robust and a verifiable quality of service value for traversing the autonomous system (AS), without revealing confidential information. Consequently, the bound can be safely conceived as a metric to be announced by each AS in the process of interdomain path selection. We show how the maximum delay value is obtained for an interdomain bandwidth demand and we propose an exact method and a numerical approximation method for computing it, neither of which rely on a complex monitoring infrastructure. Simulations with real data that illustrate the problem and validate our results are also presented. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
602.
Roux-en-Y gastric bypass (RYGB) surgery has been proven successful in weight loss and improvement of co-morbidities associated with obesity. Chronic complications such as malabsorption of micronutrients in up to 50% of patients underline the need for additional therapeutic approaches. We investigated systemic RYGB surgery effects in a liquid sucrose diet-induced rat obesity model. After consuming a diet supplemented with high liquid sucrose for eight weeks, rats underwent RYGB or control sham surgery. RYGB, sham pair-fed, and sham ad libitum-fed groups further continued on the diet after recovery. Notable alterations were revealed in microbiota composition, inflammatory markers, feces, liver, and plasma metabolites, as well as in brain neuronal activity post-surgery. Higher fecal 4-aminobutyrate (GABA) correlated with higher Bacteroidota and Enterococcus abundances in RYGB animals, pointing towards the altered enteric nervous system (ENS) and gut signaling. Favorable C-reactive protein (CRP), serine, glycine, and 3-hydroxybutyrate plasma profiles in RYGB rats were suggestive of reverted obesity risk. The impact of liquid sucrose diet and caloric restriction mainly manifested in fatty acid changes in the liver. Our multi-modal approach reveals complex systemic changes after RYGB surgery and points towards potential therapeutic targets in the gut-brain system to mimic the surgery mode of action.  相似文献   
603.
The commensal bacterium Faecalibacterium prausnitzii has unique anti-inflammatory properties, at least some of which have been attributed to its production of MAM, the Microbial Anti-inflammatory Molecule. Previous phylogenetic studies of F. prausnitzii strains have revealed the existence of various phylogroups. In this work, we address the question of whether MAMs from different phylogroups display distinct anti-inflammatory properties. We first performed wide-scale identification, classification, and phylogenetic analysis of MAM-like proteins encoded in different genomes of F. prausnitzii. When combined with a gene context analysis, this approach distinguished at least 10 distinct clusters of MAMs, providing evidence for functional diversity within this protein. We then selected 11 MAMs from various clusters and evaluated their anti-inflammatory capacities in vitro. A wide range of anti-inflammatory activity was detected. MAM from the M21/2 strain had the highest inhibitory effect (96% inhibition), while MAM from reference strain A2-165 demonstrated only 56% inhibition, and MAM from strain CNCM4541 was almost inactive. These results were confirmed in vivo in murine models of acute and chronic colitis. This study provides insights into the family of MAM proteins and generates clues regarding the choice of F. prausnitzii strains as probiotics for use in targeting chronic inflammatory diseases.  相似文献   
604.
INTRODUCTION: Mixed anxiety and depression disorder (MAD) has been recognized in ICD-10 as a diagnostic group including those anxious and depressed patients who do not fit criteria for any major axis 1 disorders. Mad is usually treated with a combination on AD and BZD although recent reports suggest that SSRI might have both anxiolytic and AD intrinsic properties. METHODS: 36 patients diagnosed of MAD (ICD-10 criteria) underwent treatment with a flexible dose of sertraline for 8 weeks. No BDZ werre allowed during the trial. Efficacy was tested with the Clinical Global Improvement Scale and with changes in Hamilton Depression and Anxiety Scales. Personality scales, including the Cloninger's TCI and the Eysenck's EPQ were used to test the predictive value of personality traits in treatment. RESULTS: Anxiety was reduced in 55% and depression in 60%. At the 8th week, 27 patients were responder (CGI 1-2). 2 patients discontinued the trial and only one due to adverse events. CONCLUSIONS: Sertraline demonstrated excellent tolerability in these MAD patients, despite the high levels of baseline anxiety in the group. Efficacy was as high as described in patients with major depression. These results warrant further placebo controlled pharmacological trials of SSRI in MAD.  相似文献   
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608.
We tested whether split effects in arithmetic (i.e., better performance on large-split problems, like 3 + 8 = 16, than on small-split problems, like 3 + 8 = 12) reflect decision processing or strategy selection. To achieve this end, we tested performance of younger and older adults, matched on arithmetic skills, on two arithmetic tasks: the addition/number comparison task (e.g., 4 + 8 ? 13; which item is the larger?) and in the inequality verification task (e.g., 4 + 8  相似文献   
609.
Many motor behaviors produced by humans and other mammals are temporally segmented. That is, sequences of rhythmic or repetitive behavior occur as a series of brief, 2- to 4-s bouts separated from each other by pauses or posture adjustments. Little is known about the physiological mechanisms underlying temporal segmentation, although several hypotheses have been advanced. Experimental and modeling studies are currently underway to gain insight into this phenomenon. One of the problems hampering advancement is the lack of relatively simple behavior models that can be studied in both humans and other mammals. We have recently reported that temporal segmentation occurs in guinea pig chewing sequences. Thus, it seems logical to explore whether temporal segmentation occurs in human chewing sequences as well. Toward this end, the current study evaluated the temporal dynamics of chewing sequences in humans. Thirteen subjects were videotaped on campus eating areas during lunch-time. Inter-occlude intervals, i.e., time between maximum jaw closures, were calculated using a custom computer program, which also recorded whether the interval represented a chew or a pause in chewing. Chewing rate, pause durations, and chewing burst durations, i.e., duration of continuous chewing uninterrupted by pauses, were calculated. Median chewing burst duration for the sample was 2.91 s. This corroborates other studies' findings of 3-s temporal segmentation in repetitive movements. We conclude that automatic chewing sequences contain temporal segmentation. Future work is required to gain insight into whether the physiological mechanisms of this time-based phenomenon are similar among different species.  相似文献   
610.
In this paper higher order impedance boundary conditions will be employed in the solution of scattering by coated conducting bodies of revolution. The higher order impedance solution reduces the total number of unknowns relative to the exact solution, and produces a system matrix which is less dense than that of the exact solution. The construction of the solution involves two distinct steps. In the first step the body of revolution is replaced by an equivalent set of electric and magnetic currents on its exterior surface which generate the true fields outside the body. An integral equation relating these currents through the free space Green's function is derived. Step two employs the higher order impedance boundary condition to relate the electric and magnetic currents on the surface of the body. This replaces the rigorous solution of the interior problem. The higher order impedance boundary conditions are derived by obtaining an exact impedance boundary condition in the spectral domain for the coated ground plane, approximating the impedances as ratios of polynomials in the transform variables, and employing the Fourier transform. The resulting spatial domain differential equations are solved in conjunction with the integral equation using the method of moments. Several examples of bistatic and monostatic radar cross section for coated bodies of revolution are used to illustrate the accuracy of the higher order impedance boundary condition solution relative to the standard impedance boundary condition solution and the exact solution. The effects of coating thickness, loss, and curvature on the accuracy of the solution are discussed  相似文献   
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