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161.
Data from experimental animals suggest that 5-hydroxytryptamine (5HT) may have an inhibitory effect on aggression, while clinical studies have found a correlation between pathological aggression and low brain 5HT. To investigate this relationship further we used amino acid mixtures designed to raise or lower the levels of the 5HT precursor, tryptophan. Normal male subjects were given tryptophan-depleted, balanced, or tryptophan-supplemented ammo acid mixtures and tested for aggression 5 hours later. The balanced amino acid mixture served as a control for the tryptophan depletion and supplementation. Testing for aggression was done using the Buss paradigm in which subjects deliver electric shocks to a (nonexistent) partner in response to stimulus tones. Duration and intensity of shock delivered were the measures of aggression, while responsivity to the stimulus tones was the measure of perceptual sensitivity. Neither tryptophan supplementation nor tryptophan depletion had any effect on these measures of aggression or perceptual sensitivity. We conclude that raising or lowering the synthesis of brain 5HT through alterations in tryptophan availability does not influence aggression in normal males as measured by the Buss task. 相似文献
162.
Heather Scott 《World Futures: Journal of General Evolution》2018,74(1):49-50
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165.
The self-reported violent experiences of adolescents living in a public-subsidized urban high-rise building were examined. This effort was part of an interdisciplinary, community-university collaboration program called the HOME (High-rise On-site Multifamily Environments) Family Support Project. A survey of violent experiences and a one-on-one structured interview were conducted with 20 adolescent residents. Results of the quantitative and qualitative analyses revealed high degrees of exposure to violence among these adolescents, concerns for their personal safety, as well as insights into what they believe adults could and should be doing to address increasing levels of community violence. The implications of these results for conducting ecologically valid research on sensitive issues with adolescents and for family support program planning are discussed. 相似文献
166.
This study examined whether employees develop perceptions about 3 different types of fit: person-organization fit, needs-supplies fit, and demands-abilities fit. Confirmatory factor analyses of data from 2 different samples strongly suggested that employees differentiate between these 3 types of fit. Furthermore, results from a longitudinal design of 187 managers supported both the convergent and discriminant validity of the different types of fit perceptions. Specifically, person-organization fit perceptions were related to organization-focused outcomes (e.g., organizational identification, citizenship behaviors, turnover decisions), whereas needs-supplies fit perceptions were related to job- and career-focused outcomes (e.g., job satisfaction, career satisfaction, occupational commitment). Although demands-abilities fit perceptions emerged as a distinct construct, they were not related to hypothesized outcomes (e.g., job performance, raises). 相似文献
167.
Eyewitness researchers have shown that witnesses accurately choosing the culprit out of a lineup reach their decisions more quickly than those erroneously choosing an innocent individual. However, this research is silent regarding how quickly or slowly witnesses must be, in absolute terms, to indicate that they are accurate or inaccurate. Across 4 studies, the authors discovered that a time boundary of roughly 10 to 12 s best differentiated accurate from inaccurate positive identifications. Witnesses making their identification faster than 10 to 12 s were nearly 90% accurate; those taking longer were roughly 50% accurate. This finding is consistent with previous research showing that accurate witnesses are more likely than inaccurate witnesses to reach their decisions automatically, that is, quickly, without conscious thought or effort. 相似文献
168.
Age differences in coping resources and satisfaction with life among middle-aged,young-old,and oldest-old adults 总被引:1,自引:0,他引:1
Hamarat E Thompson D Aysan F Steele D Matheny K Simons C 《The Journal of genetic psychology》2002,163(3):360-367
The authors examined age differences in perceived coping resources and satisfaction with life across 3 older-adult age groups (45-64, 65-74, and 75 years and older). The 98 participants represented healthy, socially active, community-residing adults. Group comparisons were made on 12 individual coping scales, and an overall coping resource effectiveness score was computed. No significant differences were found for 11 of the coping resources or for overall coping resource effectiveness. Similar consistencies in life satisfaction were found across the 3 age groups. The findings indicate that (a) for healthy adults, the oldest old cope at least as effectively as their younger counterparts, despite their likelihood of encountering increased levels of stress; and (b) psychologically, old age may be viewed as a time of resilience and fortitude. 相似文献
169.
Killeen PR Hall SS Reilly MP Kettle LC 《Journal of the experimental analysis of behavior》2002,78(2):127-160
Killeen and Hall (2001) showed that a common factor called strength underlies the key dependent variables of response probability, latency, and rate, and that overall response rate is a good predictor of strength. In a search for the mechanisms that underlie those correlations, this article shows that (a) the probability of responding on a trial is a two-state Markov process; (b) latency and rate of responding can be described in terms of the probability and period of stochastic machines called clocked Bernoulli modules, and (c) one such machine, the refractory Poisson process, provides a functional relation between the probability of observing a response during any epoch and the rate of responding. This relation is one of proportionality at low rates and curvilinearity at higher rates. 相似文献
170.
Scott WH Coyne KM Johnson MM Lausted CG Sahota M Johnson AT 《Perceptual and motor skills》2002,94(2):521-532
31 college age men and women who consume less than three caffeinated beverages per week agreed to participate as subjects in research on the effects of acute caffeine intake on low intensity task performance. All subjects performed two randomly administered test conditions: (1) caffeine (5 mg/kg) and (2) placebo on separate visits following an initial 1-hr. orientation visit. Subjects were administered the beverage 30 min. prior to performing 12 separate tests assessing basic mathematics, simple response, logical reasoning, hand-eye coordination, and spatial and assembly skills. The Spielberger State Anxiety test was administered immediately after consuming the test beverage and once again at posttest. Analysis showed that caffeine did not significantly affect performance on all tests with the exception of the peripheral awareness (hand-eye coordination) test on which performance was higher after ingesting caffeine. The placebo treatment produced no effect on state anxiety, which contrasted with a significant rise in anxiety after caffeine consumption. State anxiety values were significantly greater after caffeine treatment relative to the placebo at pretest, and this difference persisted at posttest. These results demonstrated that the dose of caffeine increased scores on state anxiety for individuals who consumed less than three caffeinated beverages weekly but had very little effect on performance of low intensity tasks, except for a hand-eye coordination test involving peripheral awareness. Perhaps longer continuous performance of more demanding tasks would be more sensitive. 相似文献