全文获取类型
收费全文 | 2212篇 |
免费 | 116篇 |
专业分类
2328篇 |
出版年
2023年 | 11篇 |
2022年 | 18篇 |
2021年 | 25篇 |
2020年 | 47篇 |
2019年 | 59篇 |
2018年 | 77篇 |
2017年 | 64篇 |
2016年 | 96篇 |
2015年 | 63篇 |
2014年 | 71篇 |
2013年 | 238篇 |
2012年 | 104篇 |
2011年 | 125篇 |
2010年 | 73篇 |
2009年 | 91篇 |
2008年 | 150篇 |
2007年 | 129篇 |
2006年 | 108篇 |
2005年 | 97篇 |
2004年 | 100篇 |
2003年 | 105篇 |
2002年 | 82篇 |
2001年 | 20篇 |
2000年 | 37篇 |
1999年 | 28篇 |
1998年 | 29篇 |
1997年 | 18篇 |
1996年 | 21篇 |
1995年 | 17篇 |
1994年 | 14篇 |
1993年 | 18篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 12篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 13篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1976年 | 10篇 |
1975年 | 6篇 |
1972年 | 5篇 |
1971年 | 8篇 |
排序方式: 共有2328条查询结果,搜索用时 0 毫秒
91.
Hollander E Phillips A King BH Guthrie D Aman MG Law P Owley T Robinson R 《CNS spectrums》2004,9(1):49-56
There are specific challenges to studying the design of pharmacologic trials in child/adolescent and adult autism, such as subject stratification and parallel versus crossover designs. This article describes how optimal study design is influenced by subject selection and outcome measures chosen. Lessons learned in study design from the Research Units on Pediatric Psychopharmacology Autism Network trial with risperidone, Seaver Center trials with fluoxetine and valproate, Dartmouth trials with amantadine, and National Institutes of Health secretin trials are highlighted. The Internet System for Assessing Autistic Children system for managing multicenter clinical trials in autism and statistical issues in autism research are also described. 相似文献
92.
This study is a follow-up study of Reynes and Lorant's studies assessing the effect of one year of judo and karate training on aggressiveness scores among young boys. The data reported here were obtained after a second year of practice, 14 judoka, 9 karateka, and 20 control participants who filled out the Buss-Perry Aggression Questionnaire three times, 1 year apart. At the first assessment, all participants, born the same year, were 8 yr. old and at the third they were 10 yr. old. Analysis indicated that after two years of practice, karate training seemed to have neither positive nor negative effects on aggressiveness scores, while judo training seemed to have a negative effect on anger scores. However, the results suggested the importance of kata or meditation in training sessions on self-control acquisition for such young boys. 相似文献
93.
Relevant logic is a proper subset of classical logic. It does not include among its theorems any ofpositive paradox A (B A)mingle A (A A)linear order (A B) (B A)unrelated extremes (A ) (B B¯)This article shows that those four formulas have different effects when added to relevant logic, and then lists many formulas that have the same effect as positive paradox or mingle. 相似文献
94.
OBJECTIVES: To determine the extent to which transition planning and community service would predict lower levels of recidivism among mentally ill juvenile offenders. DESIGN: Review of legal, medical and social service records including examination of 3-month period following community release. PARTICIPANTS: Juvenile offenders incarcerated for 6 months or more (N = 44) transitioning to community. MEASURES: Child and Adolescent Functional Assessment Scale (CAFAS), sum of different documented pre- and post-release discharge planning contacts, documented community service contacts. OUTCOMES: Re-offense during the first year post-release. RESULTS: Documented community service contacts in the 3 months following discharge were rare for mental health (20.5%), substance abuse (38.6%), financial assistance (29.5%), and school placement (34.1%). The average number of different pre-release and post-release discharge planning contacts was also low, M(SD)=1.86(1.68) and M(SD)= 2.34(1.71) respectively. Post-release discharge planning and the receipt of financial assistance and mental health services were all associated with lower levels of reoffending. CONCLUSIONS: Community transition planning, including the coordination and provision of community services, is an essential component of community reintegration for juvenile offenders and is associated with lower rates of recidivism during the first year post-discharge. 相似文献
95.
Lien MC Ruthruff E 《Journal of experimental psychology. Learning, memory, and cognition》2004,30(3):697-713
This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization. 相似文献
96.
In line with the ironic processing theory of Wegner (Psychol. Rev. 101 (1994) 34), it is often argued that the suppression of anxiety-related thoughts results in a paradoxical increase of anxiety and thought intrusions, both after and during the thought suppression. In a sample of undergraduate students (14 men, 18 women), we investigated the effects of suppressing anxious thoughts about an imminent painful electrocutaneous stimulus. During thought suppression, self-reported anxiety and frequency of anxious thoughts did not increase, and duration of anxious thoughts decreased. After thought suppression, participants experienced an increase in self-reported anxiety and the frequency of anxious thoughts. There was no effect upon thought duration. The results support the idea that suppression of anxiety-related thoughts may result in a paradoxical increase in anxiety, and may cause and/or maintain anxiety problems. 相似文献
97.
Although it is widely accepted that dieting increases the risk for bulimic pathology, this hypothesis has not been tested in a randomized experiment. Accordingly, the authors conducted an experimental test of the dietary restraint model by randomly assigning nonobese women (N = 82) to either a 6-week, low-calorie diet or a waitlist control condition. The diet intervention resulted in significant weight loss, confirming that dieting was successfully manipulated. Contrary to the restraint model, dieting resulted in significant decreases in bulimic symptoms relative to the control condition. Results converge with past findings from randomized obesity prevention and treatment trials and provide evidence that dieting does not promote bulimic pathology; rather, effective decreases in caloric intake appear to reduce bulimic symptoms. 相似文献
98.
Schwitzgebel E 《Perceptual and motor skills》2003,96(1):25-29
In the 1940s and 1950s many people in the United States appear to have thought they dreamed in black and white. For example, Middleton (1942) found that 70.7% of 277 college sophomores reported "rarely" or "never" seeing colors in their dreams. The present study replicated Middleton's questionnaire and found that a sample of 124 students in 2001 reported a significantly greater rate of colored dreaming than the earlier sample, with only 17.7% saying that they "rarely" or "never" see colors in their dreams. Assuming that dreams themselves have not changed over this time period, it appears that one or the other (or both) groups of respondents must be profoundly mistaken about a basic feature of their dream experiences. 相似文献
99.
This study investigated the acoustic characteristics of voicing in English fricative consonants produced by anterior aphasics and the effects of phonetic context on these characteristics. Three patients produced voiced and voiceless fricative-vowel syllables in isolation, following a voiced velar stop, and following a voiceless velar stop. Acoustic analyses were conducted of the amplitude and patterning of glottal excitation, as well as fricative noise duration. Results showed that, although the patients are able to coordinate the articulatory gestures for voicing in fricative consonants, they demonstrated abnormal patterns of glottal excitation in the amplitude measures, owing to weaker amplitudes of glottal excitation in voiced fricatives. Context effects failed to emerge because of dysfluent speech. These results suggest that the locus of the speech production deficit of anterior aphasics is not at the higher stages of phoneme selection or planning but rather in articulatory implementation, one related to laryngeal control. 相似文献
100.
Coalition research generally assumes that people strive to maximize their share of the coalition payoff and that they exclude others from joining a coalition if these others are not needed to obtain the coalition payoff. In two experiments, the authors show that this view is too narrow and that willingness to include such others is dependent on the extent to which people feel that exclusion affects the payoff of the excluded player. This finding was moderated by social value orientations. Proselfs were not affected by the consequences for the excluded players. Prosocials were less willing to exclude others the more harmful were the consequences of exclusion. Results are related to research on social exclusion, the do-no-harm principle, and social value orientations. 相似文献