全文获取类型
收费全文 | 5612篇 |
免费 | 247篇 |
出版年
2023年 | 42篇 |
2022年 | 28篇 |
2021年 | 46篇 |
2020年 | 111篇 |
2019年 | 111篇 |
2018年 | 149篇 |
2017年 | 145篇 |
2016年 | 200篇 |
2015年 | 140篇 |
2014年 | 122篇 |
2013年 | 612篇 |
2012年 | 257篇 |
2011年 | 319篇 |
2010年 | 187篇 |
2009年 | 220篇 |
2008年 | 241篇 |
2007年 | 286篇 |
2006年 | 221篇 |
2005年 | 217篇 |
2004年 | 229篇 |
2003年 | 231篇 |
2002年 | 201篇 |
2001年 | 109篇 |
2000年 | 98篇 |
1999年 | 102篇 |
1998年 | 105篇 |
1997年 | 79篇 |
1996年 | 79篇 |
1995年 | 76篇 |
1994年 | 85篇 |
1993年 | 55篇 |
1992年 | 71篇 |
1991年 | 42篇 |
1990年 | 52篇 |
1989年 | 31篇 |
1988年 | 23篇 |
1987年 | 37篇 |
1986年 | 36篇 |
1985年 | 37篇 |
1984年 | 34篇 |
1983年 | 52篇 |
1982年 | 42篇 |
1981年 | 36篇 |
1980年 | 30篇 |
1979年 | 40篇 |
1978年 | 45篇 |
1977年 | 28篇 |
1976年 | 29篇 |
1974年 | 13篇 |
1973年 | 13篇 |
排序方式: 共有5859条查询结果,搜索用时 15 毫秒
901.
In communities of high biodiversity, the ability to distinguish predators from non-predators is crucial for prey success.
Learning often plays a vital role in the ability to distinguish species that are threatening from those that are not. Many
prey animals learn to recognise predators based on a single conditioning event whereby they are exposed to the unknown predator
at the same time as alarm cues released from injured conspecifics. The remarkable efficiency of such learning means that recognition
mistakes may occur if prey inadvertently learn that a species is a predator when it is not. Latent inhibition is a means by
which prey that are pre-exposed to an unknown species in the absence of negative reinforcement can learn that the unknown
animal is likely not a threat. Learning through latent inhibition should be conservative because mistakenly identifying predators
as non-predators can have fatal consequences. In this study, we demonstrated that a common coral reef fish, lemon damselfish,
Pomacentrus moluccensis can learn to recognise a predator as non-threatening through latent inhibition. Furthermore, we showed that we could override
the latent inhibition effect by conditioning the prey to recognise the predator numerous times. Our results highlight the
ability of prey fish to continually update the information regarding the threat posed by other fishes in their vicinity. 相似文献
902.
Debi Davis Stephanie Corrin-Pendry Mark Savill Charlotte Doherty 《Counselling and Psychotherapy Research》2011,11(3):213-219
Rationale: To date relatively little research has examined the effectiveness of psycho‐educational courses provided in a primary care setting to adults with mild‐to‐moderate mental health concerns. Aims: To determine whether group psycho‐education could be a viable alternative to individual counselling by (1) assessing the clinical effectiveness of an 8‐week psycho‐educational course, and (2) examining the group outcomes in comparison with individual treatment outcomes from a previous study in the same counselling service. Method: A total of 57 participants attending a psycho‐educational course provided data over a 36‐month period, using the Clinical Outcomes in Routine Evaluation – Outcome Measure (CORE‐OM) pre‐ and post‐intervention. A comparison was then made with the data of 58 previous participants of individual counselling evaluation, using the same CORE‐OM system. Results: Participants reported significantly lower levels of psychological distress after attending the course and these results are comparable to outcomes measured in the same service for individual counselling, indicating that group interventions could be considered a legitimate alternative to individual counselling, thus increasing cost effectiveness and reducing waiting times. Limitations of the study and implications for practice and further investigation are considered. 相似文献
903.
Jenelle M. Slavin-Mulford Mark J. Hilsenroth Mathew D. Blagys Mark A. Blais 《Counselling and Psychotherapy Research》2011,11(2):97-104
Aims: This study examines the relationship between expert supervisors' professional experiences and their views about the importance of different psychotherapy techniques. Method: Thirty psychodynamic‐interpersonal (PI) supervisors and 13 cognitive‐behavioural (CB) supervisors (N=43) were instructed to rate 20 therapeutic techniques according to how characteristic each technique is of an ideally‐conducted session within their theoretical orientation. The measure used for this assessment was the Comparative Psychotherapy Process Scale. Results: Findings demonstrated that supervisors' beliefs about ideal therapeutic techniques are related to their number of years in post‐graduate clinical practice, training, and supervising trainees, as well as to the number of publications they have authored. Further, experience within a given orientation tends to lead to a greater endorsement of techniques within that orientation, although this finding is more uniform for CB supervisors than PI supervisors. Finally, differential types of experience lead to differential focusing on specific techniques. Discussion: The clinical importance of these findings is explored. 相似文献
904.
Mark Bennett 《Infant and child development》2011,20(4):353-363
This paper provides a brief overview of recent developmental research on themes related to children's social identities. Initially, consideration is given to the capacity for social categorization, following which attention is given to children's developing conceptions of social identities, their identification with social groups, and the consequences of identification upon various phenomena such as ingroup favouritism and well‐being. Finally, some personal thoughts on the wider political implications of this research are offered. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
905.
DeWall CN Twenge JM Koole SL Baumeister RF Marquez A Reid MW 《Emotion (Washington, D.C.)》2011,11(3):623-636
Nine experiments tested competing hypotheses regarding nonconscious affective responses to acute social exclusion and how such responses may relate to positive mental health. The results strongly and consistently indicated that acute social exclusion increased nonconscious positive affect. Compared to nonexcluded participants, excluded participants recalled more positive memories from childhood than did accepted participants (Experiment 1), gave greater weight to positive emotion in their judgments of word similarity (Experiments 2 and 3), and completed more ambiguous word stems with happy words (Experiments 4a and 4b). This process was apparently automatic, as participants asked to imagine exclusion overestimated explicit distress and underestimated implicit positivity (Experiment 3). Four final experiments showed that this automatic emotion regulation process was found among participants low (but not high) in depressive symptoms (Experiments 5 and 6) and among participants high (but not low) in self-esteem (Experiments 7 and 8). These findings suggest that acute exclusion sets in motion an automatic emotion regulation process in which positive emotions become highly accessible, which relates to positive mental health. 相似文献
906.
Current models that account for attentional processes in anxiety have proposed that high-trait anxious individuals are characterized by a hypervigilant-avoidant pattern of attentional biases to threat. We adopted a laboratory conditioning procedure to induce concomitant hypervigilance and avoidance to threat, emphasizing a putative relationship between lower-level reactive and upper-level controlled attentional mechanisms as the core account of attentional processes involved in the development and maintenance of anxiety. Eighty high- and low-trait anxious participants underwent Pavlovian conditioning to a human face. Eye tracking was used to monitor attentional changes to the conditioned stimulus (CS+) face and the neutral stimulus (CS-) face, presented at 200, 500, and 800 ms durations. The high-anxious participants developed the expected attentional bias toward the CS+ at 200 ms presentation time and attentional avoidance at 500 and 800 ms durations. Hypervigilance to aversive stimuli at 200 ms and later avoidance to the same stimuli at 500 and 800 ms were associated with higher levels of galvanic skin conductance to the CS+. The low-anxious individuals developed the opposite attentional pattern with an initial tendency to orient attention away from the aversive stimuli in the 200 ms condition and to orient attention toward aversive stimuli in the remaining time. The differential modulation between hypervigilance and avoidance elicited in the two groups by the conditioning procedure suggests that vulnerability to anxiety is characterized by a latent relationship between diverse attentional mechanisms. Within this relationship, hypervigilance and avoidance to threat operate at different stages of information processing suggesting fuzzy boundaries between early reactive and later-strategic processing of threat. 相似文献
907.
908.
An evaluation method called the Signal Evaluation Environment (SEE) was developed for use in the early stages of the design
process of peripheral warning signals while driving. Accident analyses have shown that with complex driving situations such
as intersections, the visual scan strategies of the driver contribute to overlooking other road users who have the right of
way. Salient peripheral warning signals could disrupt these strategies and direct drivers’ attention towards these road users.
To select effective warning signals, the SEE was developed as a laboratory task requiring visual–cognitive processes similar
to those used at intersections. For validation of the SEE, four experiments were conducted using different stimulus characteristics
(size, colour contrast, shape, flashing) that influence peripheral vision. The results confirm that the SEE is able to differentiate
between the selected stimulus characteristics. The SEE is a useful initial tool for designing peripheral signals, allowing
quick and efficient preselection of beneficial signals. 相似文献
909.
It is a guilty secret that many college professors sell the complimentary desk copies that they receive from textbook publishers
for cash. This article attempts to shed light on the undercover practice by looking at the resale of complimentary textbooks
by faculty from four perspectives. Part One provides an overview of the college textbook industry, the business reasons that
motivate publishers to provide complimentary desk copies to faculty, and the economic consequences of the entry of the textbooks
into the used book market. Part Two examines the legal characteristics of complimentary desk copies in terms of their ownership
and any contractual duties that may arise from their receipt. Part Three looks at legislative efforts to curb the practice,
and Part Four reviews university policies addressing the issue. In Part Five, the ethical implications of faculty selling
desk copies are examined, with a special focus on this practice in a business school. The Conclusion considers the future
of the sale of complimentary copies in light of the move to e-books and other initiatives by authors and textbook publishers
to circumvent the practice. 相似文献
910.
Biomedical research today can be generally classified as human-based or nonhuman animal-based, each with separate and distinct review boards that must approve research protocols. Researchers wishing to work with humans or human tissues have become frustrated by the required burdensome approval panel, the Institutional Review Board. However, scientists have found it is much easier to work with the animal-based research review board, the Institutional Animal Care and Use Committee. Consequently, animals are used for investigations even when scientists believe these studies should be performed with humans or human tissue. This situation deserves attention from society and more specifically the animal protection and patient advocate communities, as neither patients nor animals are well served by the present situation. 相似文献