全文获取类型
收费全文 | 1327篇 |
免费 | 34篇 |
国内免费 | 7篇 |
出版年
2021年 | 12篇 |
2020年 | 26篇 |
2019年 | 15篇 |
2018年 | 32篇 |
2017年 | 22篇 |
2016年 | 27篇 |
2015年 | 22篇 |
2014年 | 24篇 |
2013年 | 88篇 |
2012年 | 54篇 |
2011年 | 44篇 |
2010年 | 30篇 |
2009年 | 39篇 |
2008年 | 37篇 |
2007年 | 50篇 |
2006年 | 36篇 |
2005年 | 25篇 |
2004年 | 36篇 |
2003年 | 29篇 |
2002年 | 34篇 |
2001年 | 39篇 |
2000年 | 52篇 |
1999年 | 30篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1994年 | 9篇 |
1992年 | 18篇 |
1991年 | 18篇 |
1990年 | 36篇 |
1989年 | 26篇 |
1988年 | 13篇 |
1987年 | 26篇 |
1986年 | 33篇 |
1985年 | 23篇 |
1984年 | 22篇 |
1983年 | 18篇 |
1982年 | 10篇 |
1981年 | 16篇 |
1980年 | 12篇 |
1979年 | 16篇 |
1978年 | 12篇 |
1975年 | 18篇 |
1974年 | 16篇 |
1973年 | 22篇 |
1972年 | 14篇 |
1971年 | 20篇 |
1970年 | 15篇 |
1969年 | 8篇 |
1968年 | 9篇 |
1967年 | 10篇 |
排序方式: 共有1368条查询结果,搜索用时 31 毫秒
951.
In this paper, we present a generic format for adaptive vague logics. Logics based on this format are able to (1) identify
sentences as vague or non-vague in light of a given set of premises, and to (2) dynamically adjust the possible set of inferences
in accordance with these identifications, i.e. sentences that are identified as vague allow only for the application of vague
inference rules and sentences that are identified as non-vague also allow for the application of some extra set of classical
logic rules. The generic format consists of a set of minimal criteria that must be satisfied by the vague logic in casu in
order to be usable as a basis for an adaptive vague logic. The criteria focus on the way in which the logic deals with a special
⊡-operator. Depending on the kind of logic for vagueness that is used as a basis for the adaptive vague logic, this operator
can be interpreted as completely true, definitely true, clearly true, etc. It is proven that a wide range of famous logics for vagueness satisfies these criteria when extended with a specific
⊡-operator, e.g. fuzzy basic logic and its well known extensions, cf. [7], super- and subvaluationist logics, cf. [6], [9],
and clarity logic, cf. [13]. Also a fuzzy logic is presented that can be used for an adaptive vague logic that can deal with
higher-order vagueness. To illustrate the theory, some toy-examples of adaptive vague proofs are provided. 相似文献
952.
Huijbregts SC Warren AJ de Sonneville LM Swaab-Barneveld H 《Journal of abnormal child psychology》2008,36(3):323-333
This study examined whether children exposed to prenatal smoking show deficits in “hot” and/or “cool” executive functioning
(EF). Hot EF is involved in regulation of affect and motivation, whereas cool EF is involved in handling abstract, decontextualized
problems. Forty 7 to 9-year-old children (15 exposed to prenatal smoking, 25 non-exposed) performed two computerized tasks.
The Sustained Attention Dots (SA-Dots) Task (as a measure of “cool” inhibitory control) requires 400 non-dominant hand and
200 dominant hand responses. Inhibitory control of the prepotent response is required for dominant hand responses. The Delay
Frustration Task (DeFT) (as a measure of “hot” inhibitory control) consists of 55 simple maths exercises. On a number of trials
delays are introduced before the next question appears on the screen. The extent of response-button pressing during delays
indicates frustration-induced inhibitory control. Prenatally exposed children showed poorer inhibitory control in the DeFT
than non-exposed children. A dose–response relationship was also observed. In addition, prenatally exposed children had significantly
higher (dose-dependent) conduct problem- and hyperactivity-inattention scores. There were no significant group differences
in inhibitory control scores from the SA-Dots. These results indicate that children exposed to prenatal smoking are at higher
risk of hot but not cool executive function deficits. 相似文献
953.
954.
Kristie L. Young Michael A. Regan Thomas J. Triggs Karen Stephan Eve Mitsopoulos-Rubens Nebojsa Tomasevic 《Transportation Research Part F: Traffic Psychology and Behaviour》2008,11(6):434-444
The long-term effects on driver behaviour and acceptance of a seatbelt reminder system were examined in an on-road study. The system was capable of detecting seatbelt use in all seating positions and produced a two-stage visual and auditory warning if occupants were unrestrained. The effects of this system were evaluated alone and in combination with two other intelligent transport systems: intelligent speed adaptation and a following distance warning system. Twenty-three fleet car drivers drove an instrumented vehicle (SafeCar) for at least 16,500 km as part of their everyday driving. The results revealed that driver and passenger interaction with the seatbelt reminder system led to large and significant decreases in the percentage of trips where occupants were unbelted, in the percentage of total driving time spent unbelted, and in the time taken to fasten a seatbelt in response to system warnings. The seatbelt reminder system was rated by drivers as being useful, effective and socially acceptable, and led to a decrease in drivers’ subjective workload. These results were found even though the baseline pre-exposure seatbelt wearing compliance rates among participants were high. 相似文献
955.
We elaborate and defend the claim that human affective states (“feelings”) are, among other things, self-disclosing. We will show why affective intentionality has to be considered in order to understand human self-consciousness. One specific class of affective states, so-called existential feelings, although often neglected in philosophical treatments of emotions, will prove central. These feelings importantly pre-structure affective and other intentional relations to the world. Our main thesis is that existential feelings are an important manifestation of self-consciousness and figure prominently in human self-understanding. We offer an ordering of four levels of existential feelings and also give considerations in favour of the essential bodily nature of these feelings. 相似文献
956.
Makhracheva-Stepochkina D Frey S Frey JU Korz V 《Neurobiology of learning and memory》2008,89(4):545-551
Long-term potentiation (LTP) and depression (LTD) are considered as cellular models for learning and memory. We studied the impact of holeboard training on LTP in the rat CA1 hippocampal region. In 7-week-old Wistar rats a recording electrode was chronically implanted into the hippocampal pyramidal cell layer of the CA1 of the right hemisphere and a stimulation electrode into the contralateral CA3 region.Two groups of animals received a spatial holeboard training of 10 or 15 trials over 2 days on a fixed pattern of baited holes. The last trial was performed 15 min after a primed burst stimulation of the contralateral CA3, which resulted in LTP in the ipsilateral CA1. A pseudo-trained group that received a 10 trial training with changing patterns of baited holes after each trial and a group that remained in the recording chambers during the experiments served as controls. Experimental rats significantly improved their spatial performance with increasing numbers of trials, indicated by decreasing times to pick up all food pellets and by decreasing numbers of reference memory errors. A learning-related impairment of CA1-LTP measured in both the population-spike amplitude as well as the fEPSP could be noted. These results show that specific (pattern-training), but not unspecific (pseudo-training) spatial information processing prior to electrical stimulation can severely affect LTP in hippocampal area CA1. 相似文献
957.
Marius V. Peelen Bronwyn Glaser Patrik Vuilleumier Stephan Eliez 《Developmental science》2009,12(6):F16-F25
Viewing faces or bodies activates category‐selective areas of visual cortex, including the fusiform face area (FFA), fusiform body area (FBA), and extrastriate body area (EBA). Here, using fMRI, we investigate the development of these areas, focusing on the right FFA and FBA. Despite the overlap of functionally defined FFA and FBA (54%–75% overlap), we found that these regions developed along different trajectories. With age (7–32 years old), the FFA gradually increased in size and selectivity, and was significantly larger and more face‐selective in adults than children. By contrast, the size and selectivity of the FBA did not correlate with age, and were equivalent in children and adults. Whereas in adults the FFA and FBA were comparable in size, in children the FBA was on average 70% larger than the FFA. These findings suggest that, in children, the fusiform gyrus is predominantly selective for bodies, with commensurate face‐selective responses apparent later in development. Moreover, differences in the development of the FFA and FBA indicate that overlapping functional brain areas, supported by the same anatomical structure, can develop along different trajectories. 相似文献
958.
Karen Caeyenberghs Peter H. Wilson Dominique Van Roon Stephan P. Swinnen Bouwien C.M. Smits‐Engelsman 《Developmental science》2009,12(3):474-483
Motor imagery (MI) has become a principal focus of interest in studies on brain and behavior. However, changes in MI across development have received virtually no attention so far. In the present study, children (N = 112, 6 to 16 years old) performed a new, computerized Virtual Radial Fitts Task (VRFT) to determine their MI ability as well as the age‐related confluence between performance in executed and imagined movement conditions. Participants aimed at five targets, which were positioned along radial axes from a central target circle. The targets differed in width (2.5, 5, 10, 20 or 40 mm), resulting in an index of difficulty (ID) that varied from 6.9 to 2.9 bits. Performance was indexed by the linear relationship between ID and Movement Time (MT). The findings showed that executed task performance was slower than imagined performance. Moreover, conformance to Fitts’ Law during executed movement performance was obtained from a very young age. Most importantly, correlations between imagined and executed movements were low in the young participants but gradually increased across age. These age‐related changes in MI are hypothesized to reflect the children's emerging ability to represent internal models for prospective actions, consistent with the gradual unfolding of feedforward control processes. 相似文献
959.
Caregiving Behavior Is Associated With Decreased Mortality Risk 总被引:1,自引:0,他引:1
Stephanie L. Brown Dylan M. Smith Richard Schulz Mohammed U. Kabeto Peter A. Ubel Michael Poulin Jaehee Yi Catherine Kim Kenneth M. Langa 《Psychological science》2009,20(4):488-494
ABSTRACT— Traditional investigations of caregiving link it to increased caregiver morbidity and mortality, but do not disentangle the effects of providing care from those of being continuously exposed to an ailing loved one with serious health problems. We explored this possible confound in a national, longitudinal survey of elderly married individuals ( N = 3,376). Results showed that spending at least 14 hr per week providing care to a spouse predicted decreased mortality for the caregiver, independently of behavioral and cognitive limitations of the care recipient (spouse), and of other demographic and health variables. These findings suggest that it may be premature to conclude that health risks for caregivers are due to providing active help. Indeed, under some circumstances, caregivers may actually benefit from providing care. 相似文献
960.
This study provides an investigation of the nomological net for the seven primary assessment center (AC) dimensions identified by Arthur, Day, McNelly, and Eden (Personnel Psychology, 56, 125–154, 2003). In doing so, the authors provide the first robust estimates of the relationships between all primary AC dimensions with cognitive ability and the Big 5 factors of personality. Additionally, intercorrelations between AC dimensions based on sample sizes much larger than those previously available in the meta‐analytic literature are presented. Data were obtained from two large managerial samples (total N=4985). Primary data on AC dimensions, personality, and cognitive ability interrelationships were subsequently integrated with meta‐analytic data to estimate incremental validity for optimally and unit‐weighted AC dimension composites as well as overall AC ratings over psychometric tests of personality and cognitive ability. Results show that unit‐ and optimally weighted composites of construct‐based AC dimensions add incremental validity over tests of personality and cognitive ability, while overall AC ratings (including those obtained using subjective methods of data combination) do not. 相似文献