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151.
Delta (1–4 Hz) EEG power in non-rapid eye movement (NREM) sleep declines massively during adolescence. This observation stimulated the hypothesis that during adolescence the human brain undergoes an extensive reorganization driven by synaptic elimination. The parallel declines in synaptic density, delta wave amplitude and cortical metabolic rate during adolescence further support this model. These late brain changes probably represent the final ontogenetic manifestation of nature’s strategy for constructing nervous systems: an initial overproduction of neural elements followed by elimination. Errors in adolescent brain reorganization may cause mental illness; this could explain the typical age of onset of schizophrenia. Longitudinal studies of sleep EEG are enhancing our knowledge of adolescent brain maturation. Our longitudinal study of sleep EEG changes in adolescence showed that delta power, which may reflect frontal cortex maturation, begins its decline between ages 11 and 12 years and falls by 65% by age 17 years. In contrast, NREM theta power begins its decline much earlier. Delta and theta EEG frequencies are important to sleep theory because they behave homeostatically. Surprisingly, these brain changes are unrelated to pubertal maturation but are strongly linked to age. In addition to these (and other) maturational EEG changes, sleep schedules in adolescence change in response to a complex interaction of circadian, social and other influences. Our data demonstrate that the daytime sleepiness that emerges in adolescence is related to the decline in NREM delta as well as to altered sleep schedules. These longitudinal sleep data provide guideposts for studying cognitive and behavioral correlates of adolescent brain reorganization. 相似文献
152.
Gender differences in aggressive behaviour but not in anger suggest that women may express anger through behaviours that lack intent to harm or injure. Angry behaviours (injurious and noninjurious) were rated in terms of their likelihood of use when angry (N=888). Confirmatory factor analysis revealed a direct aggression factor and two further scales: explosive acts (e.g. throwing objects when alone) and defusing acts (e.g. talking to a third party). Men exceeded women on direct aggression and explosive acts, whereas women exceeded men on defusing acts. Expressive beliefs about aggression (as a loss of self-control) were higher among women and strongly associated with use of defusing acts and the avoidance of direct aggression. Instrumental beliefs about aggression (as a means of control over others) were higher among men and showed the opposite pattern of associations. We highlight the need for further work on actors' intention in relation to angry behaviours and the impact of context on these intentions. 相似文献
153.
154.
Egos inflating over time: a cross-temporal meta-analysis of the Narcissistic Personality Inventory 总被引:2,自引:0,他引:2
ABSTRACT A cross-temporal meta-analysis found that narcissism levels have risen over the generations in 85 samples of American college students who completed the 40-item forced-choice Narcissistic Personality Inventory (NPI) between 1979 and 2006 (total n =16,475). Mean narcissism scores were significantly correlated with year of data collection when weighted by sample size (β=.53, p <.001). Since 1982, NPI scores have increased 0.33 standard deviation. Thus, almost two-thirds of recent college students are above the mean 1979–1985 narcissism score, a 30% increase. The results complement previous studies finding increases in other individualistic traits such as assertiveness, agency, self-esteem, and extraversion. 相似文献
155.
Archival data from suicide survivors presenting for treatment from 1999-2005 at the Baton Rouge Crisis Intervention Center (BRCIC) were used to examine differences in those who received an active model of postvention (APM; n=150) compared to those who received a traditional passive postvention (PP, n=206). APM presented sooner for treatment (48 days) than PP (97 days). APM survivors were more likely to have been the survivor of a violent suicide. APM were more likely than PP to attend survivor support group meetings and APM attended more groups. To better understand the efficacy of APM in helping survivors, a prospective evaluation is needed. 相似文献
156.
157.
Newton T Buckley A Zurlage M Mitchell C Shaw A Woodruff-Borden J 《Psychology, health & medicine》2008,13(2):185-192
The present study examined prevalence of lack of a close confidant in a medically underserved primary care sample, and evaluated demographic, medical, and psychological correlates of patients' deficits in close, personal contact. Adult patients (n = 413) reported on confidant status and symptoms of depression and anxiety. Sociodemographic and medical information were obtained through chart review. One-quarter of patients endorsed lack of a close confidant. Past month anxiety and depression symptoms, but not medical status, were associated with unmet socioemotional needs. Implications for primary healthcare interventions are discussed. 相似文献
158.
The signing brain: the neurobiology of sign language 总被引:3,自引:0,他引:3
Most of our knowledge about the neurobiological bases of language comes from studies of spoken languages. By studying signed languages, we can determine whether what we have learnt so far is characteristic of language per se or whether it is specific to languages that are spoken and heard. Overwhelmingly, lesion and neuroimaging studies indicate that the neural systems supporting signed and spoken language are very similar: both involve a predominantly left-lateralised perisylvian network. Recent studies have also highlighted processing differences between languages in these different modalities. These studies provide rich insights into language and communication processes in deaf and hearing people. 相似文献
159.
Joseph Keim Campbell 《The Journal of Ethics》2008,12(3-4):193-201
This is the introduction to a volume of new essays in the metaphysics of moral responsibility by John Martin Fischer, Carl Ginet, Ishtiyaque Haji, Alfred R. Mele, Derk Pereboom, Paul Russell, and Peter van Inwagen. I provide some background for the essays, cover the main debates in the metaphysics of moral responsibility, and emphasize some of the authors’ contributions to this area of philosophy. 相似文献
160.
New Caledonian crows are the most proficient non-hominin tool manufacturers but the cognition behind their remarkable skills
remains largely unknown. Here we investigate if they attend to the functional properties of the tools that they routinely
use in the wild. Pandanus tools have natural barbs along one edge that enable them to function as hooking implements when
the barbs face backwards from the working tip. In experiment 1 we presented eight crows with either a non-functional (‘upside-down’)
or a functional pandanus tool in a baited hole. Four of the crows never flipped the tools. The behaviour of the four flipping
birds suggested that they had a strategy of flipping a tool when it was not working. Observations of two of the eight crows
picking up pandanus tools at feeding tables in the wild supported the lack of attention to barb direction. In experiment 2
we gave six of the eight crows a choice of either a barbed or a barbless pandanus tool. Five of the crows chose tools at random,
which further supported the findings in experiment 1 that the crows paid little or no attention to the barbs. In contrast,
a third experiment found that seven out of eight crows flipped non-functional stick tools significantly more than functional
ones. Our findings indicate that the crows do not consistently attend to the presence or orientation of barbs on pandanus
tools. Successful pandanus tool use in the wild seems to rely on behavioural strategies formed through associative learning,
including procedural knowledge about the sequence of operations required to make a successful pandanus tool.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献