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991.
This study investigates the influence of owners on their dogs’ performance in a food choice task using either different or
equal quantities of food. Fifty-four pet dogs were tested in three different conditions. In Condition 1 we evaluated their
ability to choose between a large and small amount of food (quantity discrimination task). In Condition 2 dogs were again
presented with a choice between the large and small food quantity, but only after having witnessed their owner favouring the
small quantity. In Condition 3 dogs were given a choice between two equally small quantities of food having witnessed their
owner favouring either one or the other. A strong effect of the owner on the dogs’ performance was observed. In Condition
1 dogs as a group chose significantly more often the large food quantity, thus showing their ability to solve the quantity
discrimination task. After observing their owner expressing a preference for the small food quantity they chose the large
quantity of food significantly less than in the independent choice situation. The tendency to conform to the owner’s choice
was higher when the dogs had to choose between equally small quantities of food (Condition 3) rather than between a large
and a small one (Condition 2). These results provide evidence that dogs can be influenced by their owners even when their
indications are clearly in contrast with direct perceptual information, thus leading dogs to ultimately make counterproductive
choices. 相似文献
992.
随机选取128名大学生为被试, 运用选择/无选法研究范式, 考察了不同中央执行负荷对估算策略运用的影响。结果发现:(1)中央执行负荷不影响策略分布; (2)策略运用条件、中央执行负荷影响策略执行。主次一致任务, 负荷对策略执行反应时的影响随负荷强度增大而增大, 对策略执行精确度影响不大; 而对主次不一致任务, 低负荷对策略执行反应时及精确度影响都不明显; (3)策略运用条件、中央执行负荷影响策略选择。负荷强度对策略选择反应时起重要作用, 只有当次级任务负荷高时, 干扰作用才明显; (4)成人的策略选择适应性受负荷强度的影响。无负荷条件下个体策略适应性更好。 相似文献
993.
Borrero JC Crisolo SS Tu Q Rieland WA Ross NA Francisco MT Yamamoto KY 《Journal of applied behavior analysis》2007,40(4):589-601
Using a procedure similar to the one described by Conger and Killeen (1974), we evaluated levels of attending for 25 college students who participated in either a 20-min (n = 12) or 30-min (n = 13) discussion on juvenile delinquency. Confederates delivered statements of agreement (e.g., "I agree with that point") according to independent variable-interval schedules. Pooled results were evaluated using three generalized formulations of the matching law, and showed that matching was more likely during the first 5 min of the discussion than during the last 5 min. Individual data for 7 of 9 participants were better described by the generalized response-rate matching equation than by the generalized time-allocation matching equation when response allocation was characterized in terms of frequency rather than duration. 相似文献
994.
Tomasini F 《Theoretical medicine and bioethics》2007,28(6):497-507
This article critically evaluates bettering human life. Because this involves lives that do not exist yet, the article investigates
human eugenics and enhancement through the social prism of ‘the imaginary’ (defined ‘as a set of assumptions and concepts
for thinking and speaking about human enhancement and its future direction’) [1]. “Exploring basic assumptions underlying the idea of human enhancement” investigates underlying assumptions and claims for
human enhancement. Firstly, human eugenics and enhancement entangles a factual as well as a normative claim about what improvement/betterment
maybe constitutive of. Secondly, claims about what a better life is, is often a future orientated claim about whether certain
kinds of life that do not exist yet should ever exist. Moral images of thought are introduced and how they work to make normative judgments about lives that do not
exist. This implicates the moral problem of difference, where an image of a ‘better’ life—classically expressed in eugenics
as a ‘superior’ and/or ‘normal’ life—necessarily entails inferiority and/or deviance from a norm. “Moral imagination in contemporary fiction and the history of old eugenics”,
introduces moral images in history of eugenics and demonstrates how examples fall foul of the problem. “The new (liberal)
eugenics and the moral image of therapy” examines progress in contemporary debates, the move from authoritarian to non-authoritarian
eugenics (human enhancement), and how, to some extent, this has solved the problem of difference, through liberal defence
of personal choice. “The heart of the eugenic issue” suggests that personal choice in liberal non-authoritarian eugenics is
not immune to basic drive behind all eugenic arguments; desire as lack which is expressed as the continual dissatisfaction
of not having our future expectations met.
相似文献
Floris TomasiniEmail: |
995.
Fluctuations of ovarian hormones across the menstrual cycle influence a variety of social and cognitive behaviors in primates.
For example, female rhesus monkeys exhibit heightened interest for males and increased agonistic interactions with other females
during periods of high estrogen levels. In the present study, we hypothesized that females’ preference for males during periods
of high estrogen levels is also expressed at the level of face perception. We tested four intact females on two face-tasks
involving neutral portraits of male and female rhesus monkeys, chimpanzees and humans. In the visual preference task (VP),
monkeys had to touch a button to view a face image. The image remained on the screen as long as the button was touched, and
the duration of pressing was taken as an index of the monkey's looking time for the face stimulus. In the Face-Delayed Recognition
Span Test (Face-DRST), monkeys were rewarded for touching the new face in an increasing number of serially presented faces.
Monkeys were tested 5 days a week across one menstrual cycle. Blood was collected every other day for analysis of estradiol
and progesterone. Two of the four females were cycling at the time of testing. We did not find an influence of the cycle on
Face-DRST, likely due to a floor effect. In the VP however, the two cycling individuals looked longer at conspecific male
faces than female faces during the peri-ovulatory period of the cycle. Such effects were absent for human and chimpanzee faces
and for the two noncycling subjects. These data suggest that ovarian hormones may influence females’ preferences for specific
faces, with heightened preference for male faces during the peri-ovulatory period of the cycle. Heightened interest for stimuli
of significant reproductive relevance during periods of high conception risk may help guide social and sexual behavior in
the rhesus monkey. 相似文献
996.
确定、不确定及风险状态下选择反转:“齐当别”选择方式的解释 总被引:11,自引:1,他引:10
应用广义“弱优势”(weak dominance)模型检验确定、不确定及风险状态下的选择反转现象。该模型将人们的二择一选择行为描述为一种搜寻一备择方案在主观上优越于另一备择方案的过程。即:在甲方案在某一维度上优越于乙方案,而乙方案在另一维度上优越于甲方案的情况下,为了利用“弱优势”(weak dominance)原则达成决策,人们必须在一维度上将两者间较小的差异人为地“齐同”掉,而在另一维度上将“辨别”两者间较大的差异作为最终选择的依据。因此,在每次选择时,如果不认为最大的差异都是来自同一维度,就会导致选择反转。此项研究设计了一“匹配”任务,并借此检验,在不同的决策状态下,判断两备择方案在各维度上的差异是否能预测人们的重复选择变异。总的测试-再测试结果支持“齐当别”选择方式的解释。其发现表明:重复选择之所以可能是一致的,并不是因为每次都认定被选中的备择方案具有最大值,而是因为每次选择都认定最大的差异来自一固定的维度。 相似文献
997.
998.
Richard H. Thaler 《决策行为杂志》1999,12(3):183-206
Mental accounting is the set of cognitive operations used by individuals and households to organize, evaluate, and keep track of financial activities. Making use of research on this topic over the past decade, this paper summarizes the current state of our knowledge about how people engage in mental accounting activities. Three components of mental accounting receive the most attention. This first captures how outcomes are perceived and experienced, and how decisions are made and subsequently evaluated. The accounting system provides the inputs to be both ex ante and ex post cost–benefit analyses. A second component of mental accounting involves the assignment of activities to specific accounts. Both the sources and uses of funds are labeled in real as well as in mental accounting systems. Expenditures are grouped into categories (housing, food, etc.) and spending is sometimes constrained by implicit or explicit budgets. The third component of mental accounting concerns the frequency with which accounts are evaluated and ‘choice bracketing’. Accounts can be balanced daily, weekly, yearly, and so on, and can be defined narrowly or broadly. Each of the components of mental accounting violates the economic principle of fungibility. As a result, mental accounting influences choice, that is, it matters. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
999.
选取66名大学生和40名小学四年级儿童,运用选择/无选法研究范式,采用自编乘法估算材料考察了数学焦虑对成人和四年级儿童算术策略运用的不同影响.研究结果显示:(1)数学焦虑仅影响成人在自由选择条件中策略选择的正确率.(2)数学焦虑影响儿童的策略分布、策略执行的正确率及最佳选择条件中策略选择的正确率.(3)成人和儿童策略选择的适应性(以有选条件下的策略使用正确率为指标)均受到数学焦虑的影响,低数学焦虑者的适应性明显更好.文章讨论了数学焦虑影响成人与儿童算术策略运用的不同潜在机制. 相似文献
1000.
The present study tested the predictive validity of Making Better Career Decisions (MBCD), a computer-assisted career decision-making system. Seventy clients who had used MBCD six years earlier were interviewed by telephone about their present field of study or occupation and the degree of their satisfaction with their occupational choice. The participants were divided into two groups: one consisted of clients whose chosen occupation was on the list of occupations recommended by MBCD, whereas the other consisted of clients whose chosen occupation was not on the recommended list. In the first group, 84% were highly satisfied with their occupational choice and 16% were satisfied to a moderate extent. Among those whose chosen occupation was not on the recommended list, only 38% were highly satisfied with their chosen occupation, 44% were satisfied to a moderate extent, and 18% were dissatisfied with their choice. These findings support the predictive validity of MBCD. Implications for counseling and computer-assisted career guidance systems are discussed. 相似文献