全文获取类型
收费全文 | 27392篇 |
免费 | 126篇 |
专业分类
27518篇 |
出版年
2021年 | 58篇 |
2020年 | 112篇 |
2019年 | 126篇 |
2018年 | 3596篇 |
2017年 | 2958篇 |
2016年 | 2387篇 |
2015年 | 341篇 |
2014年 | 247篇 |
2013年 | 928篇 |
2012年 | 833篇 |
2011年 | 2636篇 |
2010年 | 2660篇 |
2009年 | 1652篇 |
2008年 | 1951篇 |
2007年 | 2411篇 |
2006年 | 282篇 |
2005年 | 471篇 |
2004年 | 410篇 |
2003年 | 338篇 |
2002年 | 289篇 |
2001年 | 136篇 |
2000年 | 150篇 |
1999年 | 128篇 |
1998年 | 144篇 |
1997年 | 99篇 |
1996年 | 92篇 |
1995年 | 96篇 |
1994年 | 81篇 |
1993年 | 70篇 |
1992年 | 72篇 |
1991年 | 71篇 |
1990年 | 64篇 |
1989年 | 65篇 |
1988年 | 60篇 |
1987年 | 52篇 |
1986年 | 55篇 |
1985年 | 77篇 |
1984年 | 73篇 |
1983年 | 69篇 |
1982年 | 61篇 |
1981年 | 63篇 |
1980年 | 63篇 |
1979年 | 43篇 |
1978年 | 63篇 |
1977年 | 57篇 |
1976年 | 64篇 |
1975年 | 58篇 |
1974年 | 54篇 |
1973年 | 43篇 |
1972年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
961.
Melina M. Bersamin Beth Bourdeau Deborah A. Fisher Joel W. Grube 《Sexuality & culture》2010,14(2):157-168
The current longitudinal study explores the relationship between adolescent television use at time 1 and sexual experience
and relationship status (i.e., committed/romantic versus casual) 1 year later. The sample (N = 824) comprised youth aged 14–18. Multinomial logistic regressions predicting group membership from television exposure
variables were conducted controlling for socio-demographic characteristics and prior sexual behavior. Results indicate that
sexually inexperienced youth watched more television overall than sexually experienced youth, but less adult, premium and
music television on cable networks. Premium cable exposure predicted group membership among sexually active youth. Youth who
watched more premium cable at time 1 were more likely to be in casual relationship at last intercourse than a committed one.
A more complete understanding of media effects on adolescent sexual relationships can help guide policy development, media
education/literacy efforts, and contribute to the design of interventions to reduce the negative consequences associated with
adolescent sexual behavior. 相似文献
962.
Jean M. Twenge 《Journal of business and psychology》2010,25(2):201-210
Purpose
This article reviews the evidence for generational differences in work values from time-lag studies (which can separate generation from age/career stage) and cross-sectional studies (which cannot). Understanding generational shifts is especially important given the coming retirement of Baby Boomer workers and their replacement by those born after 1982 (GenMe/GenY/Millennials). 相似文献963.
Alden E. Gaertner Jamie L. Rathert Paula J. Fite Michael Vitulano Porché T. Wynn Jennifer Harber 《Journal of child and family studies》2010,19(5):607-616
Previous research demonstrates that aspects of parenting interact to influence child adjustment. We aimed to extend this research
by examining parenting strategies associated with behavioral control, specifically sources of parental knowledge regarding
child behavior (child disclosure, parental solicitation, parental control), as moderators of the relation between psychological
control and relational and physical/verbal aggression. Our sample included 89 children (56% male), ages 9–12. Consistent with
prior research on child adjustment, low child disclosure was the only source of parental knowledge associated with both relational
and physical/verbal aggression. Moreover, parental solicitation moderated the association between psychological control and
relational, but not physical, aggression. That is, at high levels of parental solicitation, psychological control and relational
aggression were positively related, whereas at low levels of parental solicitation, psychological control and relational aggression
were unrelated. Implications and future directions are discussed. 相似文献
964.
Ian O’Flynn 《Res Publica》2010,16(3):299-315
Although the idea of the public interest features prominently in many accounts of deliberative democracy, the relationship
between deliberative democracy and the public interest is rarely spelt out with any degree of precision. In this article,
I identify and defend one particular way of framing this relationship. I begin by arguing that people can deliberate about
the public interest only if the public interest is, in principle, identifiable independently of their deliberations. Of course,
some pluralists claim that the public interest is an implausible idea, which casts doubt on the idea that there might be something
for people to deliberate about. Yet while, following Brian Barry, we can get around this problem by defining the public interest
as an interest in which everyone shares qua member of the public, what still needs to be explained is why people should be prepared to privilege this particular capacity.
I argue that the account of political equality with which deliberative democracy is bound up offers a compelling explanation
of this sort, even if it also gives rise to some difficult questions of feasibility. I conclude by considering the charge
that any political scheme that framed the relationship between deliberative democracy and the public interest in this way
would be undesirable. 相似文献
965.
This essay explores the history of studies in analytical philosophy in China since the beginning of the last century, by dividing
into three phases. It shows that, in these phases, analytic philosophy was always at a disadvantage in confronting serious
challenges coming from both Chinese traditional philosophy and modern philosophical trends. The authors argue that Chinese
philosophers have both done preliminary studies and offered their own analyses of various problems as well as some new applications
of analytic philosophy especially in the latest period. Meanwhile, Chinese traditional philosophy was always trying to adjust
its cultural mentality in the struggle with analytic philosophy, and accommodated in its own way the rationalistic spirit
and scientific method represented in analytic philosophy. 相似文献
966.
Christopher M. Filley 《Neuropsychology review》2010,20(2):158-173
Norman Geschwind’s landmark paper in 1965, “Disconnexion Syndromes in Animals and Man,” inspired a generation of investigators
to consider the effects of focal brain lesions disrupting higher brain functions. Although Geschwind viewed disconnection
as resulting from either white or gray matter lesions, his signature article drew upon the insights of 19th century neurologists
and firmly established white matter within the vocabulary of behavioral neurology, neuropsychology, and cognitive neuroscience.
This influence, and the advent of sensitive neuroimaging techniques later in the 20th century, led to white matter gradually
gaining more attention as an essential component of distributed neural networks subserving cognition and emotion. Today, whereas
focal white matter lesions remain central to the pathogenesis of classic neurobehavioral syndromes, diffuse white matter involvement
is regarded as increasingly relevant to a wide variety of dementia syndromes and a host of neuropsychiatric disorders as well.
In parallel, better understanding of the neurobiology of brain white matter at all ages has been achieved. While much remains
to be explored, a general conceptual formulation is that white matter supports information transfer to complement the information
processing carried out by gray matter. As knowledge of the organization and functional relevance of white matter continues
to advance, improved understanding of the role of myelinated tracts in higher function can be anticipated, and with it many
clinical benefits. 相似文献
967.
Response-related mechanisms of multitasking were studied by analyzing simultaneous processing of responses in different modalities
(i.e., crossmodal action). Participants responded to a single auditory stimulus with a saccade, a manual response (single-task
conditions), or both (dual-task condition). We used a spatially incompatible stimulus-response mapping for one task, but not
for the other. Critically, inverting these mappings varied temporal task overlap in dual-task conditions while keeping spatial
incompatibility across responses constant. Unlike previous paradigms, temporal task overlap was manipulated without utilizing
sequential stimulus presentation, which might induce strategic serial processing. The results revealed dual-task costs, but
these were not affected by an increase of temporal task overlap. This finding is evidence for parallel response selection
in multitasking. We propose that crossmodal action is processed by a central mapping-selection mechanism in working memory
and that the dual-task costs are mainly caused by mapping-related crosstalk. 相似文献
968.
Robyn Bluhm 《Theoretical medicine and bioethics》2010,31(2):107-122
Robert Truog describes the controversial randomized controlled trials (RCTs) of extracorporeal membrane oxygenation (ECMO)
therapy in newborns. Because early results with ECMO indicated that it might be a great advance, saving many lives, Truog
argues that ECMO should not have been tested using RCTs, but that a long-term, large-scale observational study of actual clinical
practice should have been conducted instead. Central to Truog’s argument, however, is the idea that ECMO is an unusual case.
Thus, it is an open question whether Truog’s conclusions can be extended to other areas of medical research. In this paper,
I look at epistemological and ethical issues arising in the care of patients with chronic diseases, using ECMO as a starting
point. Both the similarities and the dissimilarities of these two cases highlight important issues in biomedical research
and support a conclusion similar to Truog’s. Observational studies of clinical practice provide the best evidence to inform
the treatment of patients with chronic disease. 相似文献
969.
Human response time (RT) data are widely used in experimental psychology to evaluate theories of mental processing. Typically,
the data constitute the times taken by a subject to react to a succession of stimuli under varying experimental conditions.
Because of the sequential nature of the experiments there are trends (due to learning, fatigue, fluctuations in attentional
state, etc.) and serial dependencies in the data. The data also exhibit extreme observations that can be attributed to lapses,
intrusions from outside the experiment, and errors occurring during the experiment. Any adequate analysis should account for
these features and quantify them accurately. Recognizing that Bayesian hierarchical models are an excellent modeling tool,
we focus on the elaboration of a realistic likelihood for the data and on a careful assessment of the quality of fit that
it provides. We judge quality of fit in terms of the predictive performance of the model. We demonstrate how simple Bayesian
hierarchical models can be built for several RT sequences, differentiating between subject-specific and condition-specific
effects. 相似文献
970.
Sunscreens with Titanium Dioxide (TiO<Subscript>2</Subscript>) Nano-Particles: A Societal Experiment
The risks of novel technologies, such as nano(bio)technology cannot be fully assessed due to the existing uncertainties surrounding
their introduction into society. Consequently, the introduction of innovative technologies can be conceptualised as a societal
experiment, which is a helpful approach to evaluate moral acceptability. This approach is illustrated with the marketing of
sunscreens containing nano-sized titanium dioxide (TiO2) particles. We argue that the marketing of this TiO2 nanomaterial in UV protective cosmetics is ethically undesirable, since it violates four reasonable moral conditions for
societal experimentation (absence of alternatives, controllability, limited informed consent, and continuing evaluation).
To remedy the current way nano-sized TiO2 containing sunscreens are utilised, we suggest five complementing actions (closing the gap, setup monitoring tools, continuing
review, designing for safety, and regulative improvements) so that its marketing can become more acceptable. 相似文献