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21.
The development of verbal and spatial working memory was investigated with an interference paradigm. Memory spans were obtained from 3 groups (8-, 10-, and 19-yr olds) under 6 different conditions: Two primary memory tasks (1 verbal, 1 spatial) were administered in isolation and in conjunction with 2 versions of a secondary task. The primary tasks required recalling a series of visually presented digits and recalling the locations of Xs in a series of visually presented grids. The secondary tasks required reporting the color of the stimuli as they were presented using either a verbal or a spatial response. Analyses revealed that all age groups showed domain-specific interference (i.e., interference by a secondary task from the same domain as the primary task), but only the 8-yr-olds also showed nonspecific interference (i.e., interference by a secondary task from a domain different than the primary memory task), suggesting that at least some executive functions do not reach adult levels of efficiency until approximately age 10. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
Reviews challenges associated with behavioral training approaches for individuals with mental retardation and mental illness in the community. Family and non-family facilitated training are considered. Professional practice issues are reviewed, and justification for multifactor behavioral assessment is offered. Future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
A. D. Baddeley, N. Thomson, and M. Buchanan (1975) suggested that articulatory rehearsal rate determines the amount of verbal material that can be maintained in working memory. In the current study, 12 children with spastic diplegic cerebral palsy (SDCP) and 38 normal children were tested on measures of articulation rate and memory span for 1-, 2-, and 3-syllable words. Across all conditions, articulation rate for the SDCP group was significantly slower than for the normal group; nonetheless, memory span was equivalent for both groups. This finding implies that covert rehearsal proceeded normally for the SDCP group, in spite of decrements in speech rate. Thus, the relationship between overt and covert rehearsal rates differs for children with SDCP compared with normal children. Findings from the current study further suggest that normal speech rates are not necessary for development of normal covert rehearsal rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
To investigate the relationship of severity of pediatric closed head injury (CHI), the contribution of frontal lobe lesions, and age at testing (6–10 yr olds vs 11–15 yr olds) to cognitive deficit, 134 head-injured patients were given the Tower of London (TOL) task and underwent magnetic resonance imaging. 89 normal controls were given the TOL for comparison. Severity of CHI and age at testing were strongly related to cognitive performance on the TOL, including the frequency of breaking the rules. Volume of frontal lobe lesion (but not extrafrontal lesion) contributed to the prediction of perfomance on the TOL even after severity of injury was taken into account. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry  相似文献   
26.
Greater use of psychological research and practice knowledge in the formulation of social policy is necessary to enhance the well-being of U.S. citizens and communities. Although historically there are instances in which psychological and social science research and practice have had a substantial influence on federal policy, for the most part the relationships among research, practice, and policy have been tenuous. Three cases in which research has substantively influenced policy over the past 80 years are reviewed: Keynesian economics, Head Start legislation, and the activities of conservative think tanks. Several recommendations are made for ways in which psychologists can enhance their influence in the policy arena, including communicating directly with policymakers regarding relevant policy findings and knowledge gleaned from practice; conducting interdisciplinary, multilevel research as well as evaluation research (including qualitative data drawn from practice settings); and networking among researchers, practitioners, policy advocates, and social action groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
This essay describes the domain of research in communication law and policy. It is based on a content analysis of research published in the journal Communication Law and Policy (1996–2004), papers presented to the Communication Law and Policy Division at annual conferences of the International Communication Association (1997–2004), as well as consideration of other resources. The most frequent areas for research were media regulation, Internet policy, and freedom of expression issues. After reviewing recent literature on the first two topics, we identified and showcased two emergent categories deserving future attention: communication and the law (particularly fair trial-free press issues) and implications of the burgeoning consolidation of media ownership.  相似文献   
28.
An extra-heavy crude oil underground upgrading process is described which involves the downhole addition of a hydrogen donor additive under steam injection conditions (280-315°C and residence times of at least 24-h). Laboratory experiments showed a 4° increase in the API gravity (from 9 to 12°) of the upgraded product, a two-fold reduction in the viscosity and, an approximately 8% decrease in the asphaltene content with respect to the original crude. Further increases on the temperature led to products with improved properties reaching 15°API at 315°C. It was found that the presence of the natural formation (catalysts) and methane (natural gas) is necessary to enhance the properties of the upgraded crude oil. From GC and GC-MS results a reaction pathway is proposed that involves hydrogen transfers from tetralin to the extra-heavy crude oil resulting in the formation of 1,2-dihydronaphthalene. This compound is then transformed into naphthalene, further upgrading of crude oil through hydrogen donation. The results of the experiments carried out in the presence and absence of the mineral formation and with an inert solid (SiC) strongly indicate that the former acts as a catalyst and not as a heat transfer matrix. Isotopic labeling studies (CD4 and 13CH4) give evidences that, most probably, methane is involved in the upgrading reactions.  相似文献   
29.
Relations of heart rate and skin conductance reactions to mildly evocative empathy-inducing slides with socioemotional functioning were examined for 154 children (mean age = 9 years, 5 months). In addition, maternal expressivity was tested as a moderator of these relations. Parents and teachers rated children's socioemotional functioning, and a behavioral measure of children's regulation was obtained. Boys who exhibited higher skin conductance and higher heart rate to slides depicting negative emotions were better regulated, less emotionally intense, and better adjusted than their peers. Furthermore, boys' regulation and adjustment were positively related to such physiological responding to negative slides if maternal negative expressivity was relatively low or moderate, but not high. Fewer findings were obtained for girls or for positive slides. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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