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The ability to generate words of a given category is found to be impaired when other words of the same category are being heard (Experiments 1–4). Little if any impairment arises from hearing words of a different category (Experiments 1, 2, and 3). This pattern of results occurs with categories defined both semantically (Experiments 1, 2, and 4) and graphemically (Experiment 3). The extent of the impairment is found to be comparable to that which occurs when other words of the same category are studied and recalled prior to generation (Experiment 4). These findings are discussed in the context of other inhibitory phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An alternate forms test was constructed with each test consisting of 40 20-second segments of tape. Each segment had built into it a conflict in degree of stress between the verbal (V) mode and the nonverbal (NV) mode, in that when V stress was high, NV stress was low, and vice versa. Ss rated the combined audio-video channels on a 9-point scale ranging from calm to stressed. Each S's ratings were correlated with V and NV criteria established by pretest judges as well as with a maximum stress criterion. Results indicated that Ss differed reliably in their preferences for V and NV cues. A difference in general sensitivity to all available cues is suggested by the finding that NV responders were able to detect stress in the V mode also, while the V responders showed little ability to respond to NV cues. A third group also correlated with the maximum stress criterion but had no V or NV mode preference.  相似文献   
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Complexes composed of peptide ligand for the serpin enzyme complex receptor covalently coupled to poly-L-lysine condensed by charge interaction with plasmid DNA direct gene transfer into receptor bearing cells. We compared intensity and duration of reporter gene expression in vitro and in vivo from serpin-enzyme receptor-directed gene transfer complexes prepared with poly-L-lysine of different chain lengths. When substituted with linker and ligand to comparable extents, DNA complexes containing short chain poly-L-lysine were larger and gave higher peak expression but significantly shorter duration of expression than those containing long chain poly-L-lysine. Both peak expression and duration of expression exceeded that observed with Lipofectin. Neither naked DNA nor DNA complexed with unsubstituted polylysine was effective in gene transfer. For in vivo experiments, complexes containing optimal ligand and degree of substitution (based on in vitro data, peptide C105Y, 11 ligands/plasmid DNA molecule) were prepared with either short chain or long chain polylysine and a beta-galactosidase expression plasmid. Following injection into the tail veins of mice, longer chain complexes gave significantly higher expression of reporter gene in lung and spleen that lasted for a significantly longer period of time than the shorter chain complexes. The short chain poly-L-lysine-DNA complexes were larger in diameter, as assessed by electron microscopy or atomic force microscopy, and gave less protection against DNase digestion in vitro than longer chain complexes. Thus, for gene transfer complexes directed at the serpin enzyme complex receptor, longer chain poly-L-lysine gave a much longer duration of expression both in vitro and in vivo. We speculate that this may be due to protection against degradation afforded the plasmid DNA by the tighter compaction produced by long chain poly-L-lysine.  相似文献   
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OBJECTIVE: To examine directly the extent to which ICD-10 hyperkinetic disorder and DSM-IV attention-deficit/hyperactivity disorder (ADHD) identify the same children with the same difficulties. METHOD: Participants were children referred for symptoms of overactivity, inattention, and impulsivity, and a normal control group. Diagnostic criteria for ICD-10 hyperkinetic disorder and DSM-IV ADHD were applied retrospectively. Four groups were identified: hyperkinetic disorder and ADHD (n = 21), ADHD only (n = 22), clinic control (n = 15), and normal control (n = 19). The groups were compared on measures reflecting the central characteristics of ADHD, neurodevelopmental functioning, academic and cognitive functioning, and the presence of conduct problems. RESULTS: There is some evidence of increased symptom severity in the combined diagnostic group. Few differences emerged on measures of neurodevelopmental, academic, and cognitive functioning. Rates of conduct disturbance were similar in both ADHD groups. CONCLUSIONS: DSM-IV criteria identify a broader group of children than those identified by ICD-10. However, there is substantial overlap between the groups formed with these different criteria.  相似文献   
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The factor structure of the Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV; Wechsler, 2008a) with the adolescent participants (ages 16–19 years; N = 400) in the standardization sample was assessed using exploratory factor analysis, multiple factor extraction criteria, and higher-order exploratory factor analyses. Results from exploratory factor analyses were not included in the WAIS-IV Technical and Interpretation Manual (Wechsler, 2008b) and are necessary for determining convergence or divergence with the reported confirmatory factor analyses. As found with the total WAIS-IV standardization sample (Canivez & Watkins, in press), the present results with the adolescent subsample found all WAIS-IV subtests (10- and 15-subtest configurations) were properly associated with their four theoretically proposed first-order factors, but only one factor extraction criterion (standard error of scree) recommended extraction of four factors. Hierarchical exploratory analyses with the Schmid and Leiman (1957) procedure found that the second-order g factor accounted for major portions of total and common variance, while the four first-order factors accounted for small portions of total and common variance. It was concluded that the WAIS-IV provides strong measurement of general intelligence in adolescents and clinical interpretation should be primarily at that level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Objective: The authors conducted a meta-analysis of empirical studies investigating associations between indices of posttraumatic stress disorder (PTSD) and intimate relationship problems to empirically synthesize this literature. Method: A literature search using PsycINFO, Medline, Published International Literature on Traumatic Stress (PILOTS), and Dissertation Abstracts was performed. The authors identified 31 studies meeting inclusion criteria. Results: True score correlations (ρ) revealed medium-sized associations between PTSD and intimate relationship discord (ρ = .38, N = 7,973, K = 21), intimate relationship physical aggression perpetration (ρ = .42, N = 4,630, K = 19), and intimate relationship psychological aggression perpetration (ρ = .36, N = 1,501, K = 10). The strength of the association between PTSD and relationship discord was higher in military (vs. civilian) samples, and when the study was conducted in the United States (vs. other country), and the study represented a doctoral dissertation (vs. published article). The strength of the association between PTSD and physical aggression was higher in military (vs. civilian) samples, males (vs. females), community (vs. clinical) samples, studies examining PTSD symptom severity (vs. diagnosis), when the physical aggression measure focused exclusively on severe violence (vs. a more inclusive measure), and the study was published (vs. dissertation). For the PTSD–psychological aggression association, 98% of the variance was accounted for by methodological artifacts such as sampling and measurement error; consequently, no moderators were examined in this relationship. Conclusions: Findings highlight a need for the examination of models explaining the relationship difficulties associated with PTSD symptomatology and interventions designed to treat problems in both areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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