全文获取类型
收费全文 | 4678篇 |
免费 | 297篇 |
专业分类
4975篇 |
出版年
2024年 | 9篇 |
2023年 | 58篇 |
2022年 | 74篇 |
2021年 | 101篇 |
2020年 | 158篇 |
2019年 | 160篇 |
2018年 | 254篇 |
2017年 | 235篇 |
2016年 | 250篇 |
2015年 | 181篇 |
2014年 | 232篇 |
2013年 | 656篇 |
2012年 | 294篇 |
2011年 | 277篇 |
2010年 | 145篇 |
2009年 | 173篇 |
2008年 | 211篇 |
2007年 | 217篇 |
2006年 | 158篇 |
2005年 | 124篇 |
2004年 | 127篇 |
2003年 | 132篇 |
2002年 | 93篇 |
2001年 | 51篇 |
2000年 | 83篇 |
1999年 | 44篇 |
1998年 | 39篇 |
1997年 | 30篇 |
1996年 | 30篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 19篇 |
1992年 | 21篇 |
1991年 | 18篇 |
1990年 | 11篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 9篇 |
1984年 | 12篇 |
1983年 | 12篇 |
1982年 | 25篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 14篇 |
1978年 | 10篇 |
1975年 | 10篇 |
1972年 | 11篇 |
1971年 | 11篇 |
1970年 | 13篇 |
1966年 | 9篇 |
排序方式: 共有4975条查询结果,搜索用时 15 毫秒
271.
Janssen D Schöllhorn WI Newell KM Jäger JM Rost F Vehof K 《Human movement science》2011,30(5):966-975
The aim of the study was to train and test support vector machines (SVM) and self-organizing maps (SOM) to correctly classify gait patterns before, during and after complete leg exhaustion by isokinetic leg exercises. Ground reaction forces were derived for 18 gait cycles on 9 adult participants. Immediately before the trials 7–12, participants were required to completely exhaust their calves with the aid of additional weights (44.4 ± 8.8 kg). Data were analyzed using: (a) the time courses directly and (b) only the deviations from each individual’s calculated average gait pattern. On an inter-individual level the person recognition of the gait patterns was 100% realizable. Fatigue recognition was also highly probable at 98.1%. Additionally, applied SOMs allowed an alternative visualization of the development of fatigue in the gait patterns over the progressive fatiguing exercise regimen. 相似文献
272.
273.
Building a Committed Hospice Volunteer Workforce—Do Variables at the Experience Stage Matter? 下载免费PDF全文
Claudia Schusterschitz Magdalena Flatscher‐Thöni Andrea M. Leiter‐Scheiring Willi Geser 《Journal of community & applied social psychology》2014,24(5):422-438
Volunteers are crucial to the survival of non‐profit organisations, who therefore have a fundamental interest in sustaining voluntary engagement over time. A central variable regarding sustained voluntary engagement is volunteers' organisational commitment, which has so far been a neglected research issue. The study at hand therefore explicitly focuses on hospice volunteers' commitment. Starting from the assumption that variables at the experience stage of volunteerism may be relevant in predicting volunteer commitment, questionnaire data on volunteers' motives, motive fulfilment and role identity were collected in a sample of hospice volunteers (N = 276). Results of multiple regression analyses show positive relationships between altruistic motive fulfilment and a volunteer role identity on the one hand and volunteer commitment on the other. Observed interaction effects imply that altruistic motive fulfilment is of importance both at the initial phase of volunteering and for long‐term volunteers. Moreover, interaction effects provide evidence that the fulfilment of egoistic motives is of particular importance amongst volunteers to whom egoistic motives are central. Thus, the fulfilment of altruistic motives and facilitating the development of a volunteer role identity should be permanent concerns in building a committed workforce. Egoistic motive fulfilment in contrast is of special relevance, when egoistic motives for volunteering are strong. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
274.
Cynthia Suveg Marni L. Jacob Monica Whitehead Anna Jones Julie Newman Kingery 《Anxiety, stress, and coping》2014,27(5):494-508
Social difficulties are commonly associated with anxiety disorders in youth, yet are not well specified in the literature. The aim of this study was to identify patterns of social experiences in clinically anxious children and examine the associations with indices of emotional functioning. A model-based cluster analysis was conducted on parent-, teacher-, and child-reports of social experiences with 64 children, ages 7–12 years (M = 8.86 years, SD = 1.59 years; 60.3% boys; 85.7% Caucasian) with a primary diagnosis of separation anxiety disorder, social phobia, and/or generalized anxiety disorder. Follow-up analyses examined cluster differences on indices of emotional functioning. Findings yielded three clusters of social experiences that were unrelated to diagnosis: (1) Unaware Children (elevated scores on parent- and teacher-reports of social difficulties but relatively low scores on child-reports, n = 12), (2) Average Functioning (relatively average scores across all informants, n = 44), and (3) Victimized and Lonely (elevated child-reports of overt and relational victimization and loneliness and relatively low scores on parent- and teacher-reports of social difficulties, n = 8). Youth in the Unaware Children cluster were rated as more emotionally dysregulated by teachers and had a greater number of diagnoses than youth in the Average Functioning group. In contrast, the Victimized and Lonely group self-reported greater frequency of negative affect and reluctance to share emotional experiences than the Average Functioning cluster. Overall, this study demonstrates that social maladjustment in clinically anxious children can manifest in a variety of ways and assessment should include multiple informants and methods. 相似文献
275.
Johanna Rahmqvist Michael B. Wells Anna Sarkadi 《Journal of child and family studies》2014,23(5):934-944
Triple P is a parenting program that aims to prevent behavioral, emotional, and developmental problems in children. Because Triple P is a new parenting program in Sweden, it is important to see how parents felt about the intervention. The aim of this study was to find out why parents of preschool children chose to participate in Triple P in Sweden, what they thought of the Triple P curriculum, and how the program related to their parenting philosophy in general. This is a qualitative study using semi-structured interviews with seven mothers and three fathers who participated in Triple P. The interviews were transcribed verbatim and were analysed using Malterud’s method of Systematic Text Condensation. Parents chose to participate in Triple P for several reasons: they wanted to learn more about the intervention; they had specific problems that they sought help for; or they felt encouraged to participate due to advertisements and recommendations from friends. Of the Triple P curriculum, the participants especially enjoyed the “directed discussion” technique, the positive reinforcement sections, and the instructions on how to communicate effectively with their child by staying calm, close, and maintaining eye contact. It was important for many of the parents to feel validated and respected, and they liked having discussions with the preschool teacher rather than being told what to do. Parents in this Swedish sample generally liked and selectively used the strategies they learned from participating in Triple P, depending on how well these fit with their own parenting experiences and philosophy. 相似文献
276.
Lisa Henderson Anna Powell M. Gareth Gaskell Courtenay Norbury 《Developmental science》2014,17(6):858-871
Autism spectrum disorder (ASD) is characterized by rich heterogeneity in vocabulary knowledge and word knowledge that is not well accounted for by current cognitive theories. This study examines whether individual differences in vocabulary knowledge in ASD might be partly explained by a difficulty with consolidating newly learned spoken words and/or integrating them with existing knowledge. Nineteen boys with ASD and 19 typically developing (TD) boys matched on age and vocabulary knowledge showed similar improvements in recognition and recall of novel words (e.g. ‘biscal’) 24 hours after training, suggesting an intact ability to consolidate explicit knowledge of new spoken word forms. TD children showed competition effects for existing neighbors (e.g. ‘biscuit’) after 24 hours, suggesting that the new words had been integrated with existing knowledge over time. In contrast, children with ASD showed immediate competition effects that were not significant after 24 hours, suggesting a qualitative difference in the time course of lexical integration. These results are considered from the perspective of the dual‐memory systems framework. 相似文献
277.
Caitlin E. V. Mahy Nora Vetter Nina Kühn-Popp Carolin Löcher Susan Krautschuk Matthias Kliegel 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2014,21(2):129-145
The primary aim of this study was to examine the impact of an inhibition manipulation on the effect of age on theory of mind (ToM) in an ecologically valid, affective ToM task. Participants were 30 young and 30 old adults. The Cambridge Mindreading Face-Voice Battery was used to measure ToM; in addition, measures of fluid and crystallized intelligence were taken. Participants were subjected to three levels of inhibitory demand during ToM reasoning: emotional inhibition, non-emotional inhibition, and no inhibition. Old adults performed worse than young adults. The emotional and non-emotional inhibition conditions resulted in worse ToM performance compared to the no inhibition condition. There were no differences in the impact of the inhibition conditions on old and young adults. Regression analyses suggested that old adults’ crystallized intelligence was a significant predictor of ToM performance, whereas it did not predict young adults’ ToM performance. Results are discussed in terms of verbal ability as a possible compensatory mechanism in coping with verbal inhibitory load in ToM reasoning. 相似文献
278.
Petra Sandberg Michael Rönnlund Lars Nyberg Anna Stigsdotter Neely 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2014,21(5):577-605
There is a growing body of research on the modifiability of executive functions in different stages of life. Previous studies demonstrate robust training effects but limited transfer in younger and particularly in older adults. The aim of the present study was to investigate whether a theoretically derived intervention for executive functioning, addressing several basic processes (updating, shifting, and inhibition), can induce transfer effects in early and late adulthood. Fifty-nine healthy adults, 29 young and 30 older adults, were randomly assigned to either training or no-contact control groups. The training groups received 15 sessions of executive process training for about 45 min/session during 5 weeks. A test battery including a criterion task and near, intermediate, and far transfer tasks was administered before and after training. Results showed pronounced age-equivalent gains on the criterion task. Near transfer was seen to non-trained updating and inhibition tasks for the young and older trained participants. However, only the young adults showed intermediate transfer to two complex working memory tasks. No far transfer effects were seen for either age group. These findings provide additional evidence for age-related constraints in the ability to generalize acquired executive skills, and specifically show that training of multiple executive processes is not sufficient to foster transfer beyond the very near in older adults. 相似文献
279.
Sebastian Rödl 《Philosophical explorations》2014,17(3):304-316
The second person is often set in contrast to the first person. And there is a contrast. It does not reside in a difference of what is thought as I from what is thought as you. For that is not different. The contrast is that of monadic and dyadic predication, action and transaction. It is the contrast, not of I and You, but of I and I–You. The second person does not add a You to an I. It divides the I and makes it a relation. We consider, first, the form of predication that is common to first- and second-person thought. Then, we define the second person as a species of this form of thought. Last, we find the source and condition of this form of thought in a thought of this very form. This thought, being the source of its own form, is one of which one cannot be conscious from outside it. It is a last word, or, better, a first word.1 相似文献
280.
The protection of offspring against predators and competitors is especially important in organisms using spatially separated breeding resources, impeding the offspring’s chances to escape. One example of such isolated reproductive resources are phytotelmata (small water bodies in plant axils), exploited by the Neotropical poison frog Ranitomeya variabilis (Dendrobatidae) for both clutch and tadpole deposition. Because poison frog tadpoles are often cannibalistic, parents tend to avoid deposition with conspecifics. Previous studies have shown that this avoidance is based on chemical cues produced by conspecific tadpoles. Further, cues produced by phylogenetically less-related tadpoles (Bufonidae) were avoided for clutch but not tadpole depositions. We analyzed how the different responses to tadpole cues are triggered. We tested the reactions of parental R. variabilis to tadpole cues of species differing in two aspects: whether or not they are dendrobatids, and whether or not they reproduce in phytotelmata. We found that for clutch deposition, tadpole cues were always avoided, i.e., all tadpoles were treated by the frogs as if they pose a danger to the eggs. However, responses varied for tadpole depositions: while dendrobatid larvae living in phytotelmata were avoided, those breeding in streams were not. Non-poison frog tadpoles were ignored when associated with habitat other than phytotelmata, but they were preferred when living in phytotelmata. This suggests that both phylogeny and tadpole habitat are important triggers for the decisions made by R. variabilis. Only tadpoles using the same breeding resources are considered as relevant for the frog’s own larvae (i.e., as a potential danger or food resource), while further decisions are related to evolutionary relationship. 相似文献