全文获取类型
收费全文 | 5972篇 |
免费 | 358篇 |
国内免费 | 1篇 |
出版年
2023年 | 49篇 |
2022年 | 59篇 |
2021年 | 103篇 |
2020年 | 137篇 |
2019年 | 186篇 |
2018年 | 248篇 |
2017年 | 253篇 |
2016年 | 256篇 |
2015年 | 183篇 |
2014年 | 232篇 |
2013年 | 766篇 |
2012年 | 321篇 |
2011年 | 375篇 |
2010年 | 218篇 |
2009年 | 217篇 |
2008年 | 293篇 |
2007年 | 250篇 |
2006年 | 211篇 |
2005年 | 182篇 |
2004年 | 217篇 |
2003年 | 198篇 |
2002年 | 164篇 |
2001年 | 102篇 |
2000年 | 107篇 |
1999年 | 84篇 |
1998年 | 58篇 |
1997年 | 54篇 |
1996年 | 52篇 |
1995年 | 46篇 |
1994年 | 44篇 |
1993年 | 30篇 |
1992年 | 49篇 |
1991年 | 37篇 |
1990年 | 52篇 |
1989年 | 53篇 |
1988年 | 44篇 |
1987年 | 29篇 |
1986年 | 35篇 |
1985年 | 37篇 |
1984年 | 37篇 |
1983年 | 23篇 |
1982年 | 25篇 |
1981年 | 17篇 |
1980年 | 21篇 |
1979年 | 24篇 |
1978年 | 19篇 |
1977年 | 11篇 |
1975年 | 14篇 |
1973年 | 9篇 |
1972年 | 14篇 |
排序方式: 共有6331条查询结果,搜索用时 15 毫秒
201.
Developmental trajectories of peer-nominated aggression, risk factors at baseline, and outcomes were studied. Peer nominations of aggression were obtained annually from grades 1 to 3. Three developmental trajectories were identified: an early-onset/increasers trajectory with high levels of peer-nominated aggression at elementary school entry and increasing levels throughout follow-up; a moderate-persistent trajectory of aggression in which children were characterized by moderate levels of physical aggression at baseline; and a third trajectory with stable low levels of aggression. Children following the early-onset/increasers trajectory showed physical forms of aggression at baseline. Male gender and comorbid attention deficit/hyperactivity problems, oppositional defiant problems and poor prosocial behavior plus negative life events predicted which children would follow the early-onset/increasers trajectory of aggression. The outcomes associated with the early-onset/increaser children suggest high risk for chronically high levels of aggressive behavior. 相似文献
202.
Delayed attentional engagement in the attentional blink 总被引:6,自引:0,他引:6
Nieuwenstein MR Chun MM van der Lubbe RH Hooge IT 《Journal of experimental psychology. Human perception and performance》2005,31(6):1463-1475
Observers often miss the 2nd of 2 visual targets (first target [T1] and second target [T2]) when these targets are presented closely in time; the attentional blink (AB). The authors hypothesized that the AB occurs because the attentional response to T2 is delayed by T1 processing, causing T2 to lose a competition for attention to the item that follows it. The authors investigated this hypothesis by determining whether the AB is attenuated when T2 is precued. The results from 4 experiments showed that the duration and magnitude of the AB were substantially reduced when T2 was precued. The observed improvement in T2 report did not occur at the expense of T1 report, suggesting that processing of T1 was already completed or was at least protected when the cue was presented. The authors conclude that, during the AB, there is a delay between detection and the selection of target candidates for consolidation in short-term memory. 相似文献
203.
The aim of the experiment was to investigate how bi-phasic hitting movements are organized to comply with both impact and temporal precision constraints. 'Bi-phasic' refers to a sequential movement with a preparatory movement away from the interception location followed by a strike phase. The interception location was fixed, as the motion of the hitting device was constrained to follow a straight path orthogonal to that of the approaching balls. We manipulated the required temporal precision by projecting balls with different constant approach speeds (1, 1.5, and 2m/s). Different impact constraints were imposed by instructing participants first to simply hit the ball and subsequently to hit the ball to a designated target area located either 55 or 105 cm away from the interception location. We determined several kinematic variables and used Principal Component Factor Analysis to classify these variables. The analysis revealed two independent factors: a 'velocity' factor (formed by impact velocity, peak velocity of the preparatory phase, peak velocity of the strike phase, and amplitude of the strike) and a 'timing' factor (formed by onset of the preparatory phase, moment of peak velocity of the preparatory phase, and onset of the strike phase). The 'velocity' factor scaled significantly with the required impact constraint and the 'timing' factor scaled significantly with ball speed. 相似文献
204.
Janet Sigal Margaret S. Gibbs Carl Goodrich Tayyab Rashid Afroze Anjum Daniel Hsu Carrol S. Perrino Hale Bolak Boratav Aggie Carson-Arenas Berna van Baarsen Joop van der Pligt Wei-Kang Pan 《Sex roles》2005,52(3-4):201-215
Male and female university students from the United States, Canada, Germany, the Netherlands, Ecuador, Pakistan, the Philippines, Taiwan, and Turkey read a standardized scenario in which a male professor was accused of sexually harassing a female graduate student. Respondents from individualist countries judged the professor to be guilty of sexual harassment more often than did those from collectivist countries. Women rendered significantly more guilty judgments and assigned more severe punishments to the accused professor than did men. Implications for the individualist–collectivist classification system and cross-cultural research are discussed. 相似文献
205.
Highly hypnotizable participants were given a posthypnotic suggestion to feel a flash of disgust whenever they read an arbitrary word. They were then asked to rate moral transgressions described in vignettes that either did or did not include the disgust-inducing word. Two studies show that moral judgments can be made more severe by the presence of a flash of disgust. These findings suggest that moral judgments may be grounded in affectively laden moral intuitions. 相似文献
206.
Neuroleptic malignant syndrome (NMS) is a life threatening medical state complicating the use of antipsychotic medications and other drugs that affect the dopaminergic system on administration or withdrawal. The condition was recognised nearly half a century ago, shortly after the discovery of antipsychotic medications. However, there are still no systematic studies about NMS. There are no definitive guidelines on its treatment. Although early recognition is emphasised and usually possible, delayed diagnosis is not rare. We here report on a case of NMS complicated by renal failure, and possibly respiratory failure. The report underscores the seriousness of delayed diagnosis and puts forward a comprehensive management recommendation based on our experience and the existing literature. 相似文献
207.
We modified Bruce, Dolan, and Phillips-Grant's (2000) threshold procedure for determining the wane of childhood amnesia. In two experiments, undergraduates labelled childhood events (e.g., your first permanent tooth came in) as know or recollect memories and estimated their age at the event's occurrence. In both studies the estimated transition from mostly know memories to mostly recollect memories was roughly 4.7 years. This transition estimate was replicated in a sample of adults (ages 24-65 years) with both Bruce et al.'s event-generation task and the Experiment 1a questionnaire. By contrast, in two experiments a transition estimate of roughly 6 years was found for undergraduates' memories of public events (e.g., the Challenger explosion). The wane of childhood amnesia appears to occur around 4.7 years. 相似文献
208.
We presented a Web questionnaire to 139 physicians and medical researchers and 109 laypeople. The subjects made judgments of badness and importance of prevention for eight medical conditions at each of seven different probability levels. By assuming that the response to each of the 56 risks was monotonically related to transformations of the probability and of the disutility of the condition, we could assess the relative effect of probability and disutility on each subject's judgments. Physicians' judgments were more sensitive than laypeople's judgments to changes in probability. Older and female laypeople were less sensitive to probability (and correspondingly, more responsive to differences in severity among medical conditions). Laypeople varied more than physicians in their responsiveness to probability. These results point to general individual differences in the effect of probability on evaluations of medical risks. They may also provide insight into causes and noncauses of physician-patient miscommunication. 相似文献
209.
Deliberate self-harm (DSH) is a strong predictor of suicide in schizophrenia. The aim of this review was to identify risk factors for DSH in schizophrenia. This systematic review of the international literature examined cohort and case-control studies of patients with schizophrenia or related diagnoses that reported DSH as an outcome. Studies were identified by searching electronic databases and reference lists, and by consulting international experts. Fourteen studies met the eligibility criteria. Of the 29 variables examined by two or more studies, five (past or recent suicidal ideation, previous DSH, past depressive episode, drug abuse or dependence, and higher mean number of psychiatric admissions) were associated with an increased risk of DSH, and one (unemployment) was associated with a reduced risk. Schizophrenic patients with these risk factors need careful follow-up and monitoring, with treatment of any associated comorbid depression or drug abuse. Large, prospective studies of DSH in schizophrenia are needed to further define risk factors and to build on the findings of this review. 相似文献
210.
Developing human-nonhuman chimeras in human stem cell research: ethical issues and boundaries 总被引:1,自引:0,他引:1
The transplantation of adult human neural stem cells into prenatal non-humans offers an avenue for studying human neural cell development without direct use of human embryos. However, such experiments raise significant ethical concerns about mixing human and nonhuman materials in ways that could result in the development of human-nonhuman chimeras. This paper examines four arguments against such research, the moral taboo, species integrity, "unnaturalness," and human dignity arguments, and finds the last plausible. It argues that the transfer of human brain or retinal stem cells to nonhuman embryos would not result in the development of human-nonhuman chimeras that denigrate human dignity, provided such stem cells are dissociated. The article provides guidelines that set ethical boundaries for conducting such research that are consonant with the requirements of human dignity. 相似文献