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921.
E.?Paul?WileytoEmail author Janet?Audrain-Mcgovern Leonard?H.?Epstein Caryn?Lerman 《Behavior research methods》2004,36(1):41-51
The monetary choice questionnaire (MCQ) and similar computer tasks ask preference questions in order to ascertain indifference,
the perceived equivalence of immediate versus larger delayed rewards. Indifference data are then fitted with a hyperbolic
function, summarizing the decline in perceived value with delay time. We present a fitting method that estimates the hyperbolic
parameterk directly from survey responses. Binary preferences are modeled as a function of time (X2) and a transformed reward ratio (X
1), yielding logistic regression coefficients β2 and β1. The hyperbolic parameter emerges ask = β2/β1, where the logistic predictedp = .5 (the definition of indifference). The MCQ was administered to 1,073 adolescents and was scored using both standard and
logistic methods. The means for ln(k) were similar (standard, −4.53; logistic, −4.51), and the results were highly correlated (ρ = .973). Simulated MCQ data showed
thatk was unbiased, except where β1 ≥ −1, indicating a vague survey response. Jackknife standard errors provided excellent coverage. 相似文献
922.
David?A.?WashburnEmail author Michael?J.?Rulon Jonathan?P.?Gulledge 《Behavior research methods》2004,36(2):173-179
Many exciting findings have been reported in the 15 years since monkeys were first demonstrated to have the capacity to perform
computerized tasks. The present data indicate that albino rats can also learn to respond to computer-generated stimuli by
manipulating a joystick. Although the rat’s control of the cursor is not as skillful as has been reported for primate species,
it is clearly better than chance and suggests the great potential for comparative investigation afforded by use of the computer
test system. 相似文献
923.
Fiction is not always accurate, and this has consequences for readers. In laboratory studies, the reading of short stories
led participants to produce story errors as facts on a later test of general knowledge (Marsh, Meade, & Roediger, 2003). The
present article describes these story stimuli in detail, so that interested researchers will be able to use the stimuli and
change them as needed for particular research projects. This article provides instructions for using the stories and suggestions
for modifying them; it is a manual for one way of creating suggestibility. The full set of stories and reading comprehension
questions may be downloaded fromwww.psychonomic.org/archive/. 相似文献
924.
We present a computational model for human texture perception which assigns functional principles to the Gestalt laws of similarity and proximity. Motivated by early vision mechanisms, in the first stage, local texture features are extracted by utilizing multi-scale filtering and nonlinear spatial pooling. In the second stage, features are grouped according to the spatial feature binding model of the competitive layer model (CLM; Wersing et al. 2001). The CLM uses cooperative and competitive interactions in a recurrent network, where binding is expressed by the layer-wise coactivation of feature-representing neurons. The Gestalt law of similarity is expressed by a non-Euclidean distance measure in the abstract feature space with proximity being taken into account by a spatial component. To choose the stimulus dimensions which allow the most salient similarity-based texture segmentation, the feature similarity metrics is reduced to the directions of maximum variance. We show that our combined texture feature extraction and binding model performs segmentation in strong conformity with human perception. The examples range from classical microtextures and Brodatz textures to other classical Gestalt stimuli, which offer a new perspective on the role of texture for more abstract similarity grouping. 相似文献
925.
The problem of constructing computational models of space that mimic those found in human spatial reasoning is addressed. This paper extends a formal model that addressed point objects in a 2D world to include the presence of line objects and barriers. The problem consists of determining an appropriate global model for the spatial configuration given a sequence of local views or observations. A formal model is proposed based on constraint network theory. The model leads to the identification of stable regions within which perceptual information about the environment changes slowly, and zones of transition within which the perceptual information changes more quickly. A special case of transition zones is a gateway, which may be viewed as a kind of discontinuity or singularity in the model. It is expected that the model obtained will be used to mimic human mental representations of navigable outdoor environments. 相似文献
926.
927.
Beatrice?M.?de?OcaEmail author Michael?S.?Fanselow 《Integrative psychological & behavioral science》2004,39(4):318-333
Defensive responses to a cat were observed in rats given excitotoxic lesions of the central nucleus of the amygdala (ACe),
dorsolateral periaqueductal gray (dlPAG), ventral periaqueductal gray (vPAG), or sham lesions. Rats were placed adjacent to
a compartment containing a cat. Sham-lesioned rats avoided the area nearest the cat and preferred the area furthest away from
the cat. They also exhibited numerous defensive responses including, climbing, escape from the apparatus, and freezing. Rats
with lesions of the ACe reacted like the sham lesioned rats by preferring the area of the apparatus furthest from the cat,
however they climbed and escaped significantly less than sham lesioned rats. Avoidance of the area adjacent to the cat was
attenuated in rats with lesions of the vPAG. Climbing along the walls of the apparatus was also attenuated in rats with lesions
of the vPAG. Escapes from the apparatus were not significantly reduced by lesions of the vPAG and dlPAG. Thus, ACe lesions
attenuated climbing and eliminated escapes, but did not impair locomotion of the rat away from the cat. 相似文献
928.
Hugo?WesterlundEmail author Anna?Bergstr?m T?res?Theorell 《Integrative psychological & behavioral science》2004,39(1):3-15
Thirty-two female participants in a mobilising labour market programme offering temporary, alternative employment in Sweden
were followed longitudinally for one year, including a six month post participation follow-up period. It can be hypothesised
that an important aspect of the physiological effects of unemployment is a change in the balance between anabolic and catabolic
activities in the body and that re-employment should lead to a shift towards anabolism. An earlier study of a smaller subset
of the data, however, including both men and women, showed increased prolactin and decreased dehydroepiadrosterone sulphate
(DHEA-s) levels, contrary to the initial hypothesis. In the present analysis, intended to elucidate these results, psychophysiological
data were summarised in two indices, one connected with anabolism (made up of testosterone and DHEA-s) and one with catabolism
(prolactin, γ-glutamyl transferase, aspartate amino transferase, α levuline amino transferase, and body mass index). In addition,
self-rated anxiety, depression, hopelessness and personal control were analysed. The results indicate that the effect of ‘better’
activities within the programme was a temporary increase in anabolism, possibly indicating lower stress levels, and the effect
of ‘worse’ activities, on the one hand, a temporary decrease in the catabolic index, probably reflecting repressed alcohol
consumption, and, on the other hand, impaired anabolism. There was also a general but transient decrease in depressiveness
measured by the Hospital Anxiety and Depression Scale. The results seem to imply that it is difficult to achieve lasting effects
through a relatively short participation in a mobilising programme. 相似文献
929.
Shirley?TellesEmail author Meesha?Joshi Manoj?Dash P.?Raghuraj K.?V.?Naveen H.?R.?Nagendra 《Integrative psychological & behavioral science》2004,39(2):119-125
The study aimed at determining whether novices to yoga would be able to reduce their heart rate voluntarily and whether the
magnitude of reduction would be more after 30 days of yoga training. Two groups (yoga and control,n=12 each) were assessed on Day 1 and on Day 30. During the intervening 30 days, the yoga group received training in yoga techniques
while the control group carried on with their routine. At each assessment the baseline heart rate was recorded for one minute,
this was followed by a six-minute period during which participants were asked to attempt to voluntarily reduce their heart
rate, using any strategy. Both the baseline heart rate and the lowest heart rate achieved voluntarily during the six-minute
period were significantly lower in the yoga group on Day 30 compared to Day 1 by a group average of 10.7 beats per minute
(i.e., bpm) and 6.8 bpm, respectively (p<.05, Wilcoxon paired signed ranks test). In contrast, there was no significant change in either the baseline heart rate or
the lowest heart rate achieved voluntarily in the control group on Day 30 compared to Day 1. The results suggest that yoga
training can enable practitioners to use their own strategies to reduce the heart rate, which has possible therapeutic applications. 相似文献
930.
Keith?D.?Huff Yukiko?Asaka Amy?L.?Griffin William?P.?Berg Matthew?A.?Seager Stephen?D.?BerryEmail author 《Integrative psychological & behavioral science》2004,39(1):16-23
Analysis of naturalistic chewing patterns may provide insight into mapping the neural substrates of jaw movement control systems,
including their adaptive modification during the classically conditioned jaw movement (CJM) paradigm. Here, New Zealand White
rabbits were administered food and water stimuli orally to evaluate the influence of stimulus consistency on masticatory pattern.
Chewing patterns were recorded via video camera and movements were analyzed by computerized image analysis. The mandibular
kinematics, specifically the extent of dorsal/ventral, medial/lateral, and rostral/caudal movement, were significantly larger
in food-evoked than water-evoked chewing. Water-evoked chewing frequency, however, was significantly higher than that of food-evoked
movements. In light of known cortical mastication modulatory centers, our findings implicate different neural substrates for
the responses to food and water stimuli in the rabbit. A detailed delineation of jaw movement patterns and circuitry is essential
to characterize the neural substrates of CJM. 相似文献