全文获取类型
收费全文 | 7145篇 |
免费 | 284篇 |
国内免费 | 4篇 |
专业分类
7433篇 |
出版年
2023年 | 59篇 |
2022年 | 72篇 |
2021年 | 95篇 |
2020年 | 146篇 |
2019年 | 154篇 |
2018年 | 231篇 |
2017年 | 250篇 |
2016年 | 237篇 |
2015年 | 187篇 |
2014年 | 234篇 |
2013年 | 853篇 |
2012年 | 397篇 |
2011年 | 364篇 |
2010年 | 213篇 |
2009年 | 233篇 |
2008年 | 276篇 |
2007年 | 316篇 |
2006年 | 247篇 |
2005年 | 206篇 |
2004年 | 212篇 |
2003年 | 186篇 |
2002年 | 155篇 |
2001年 | 130篇 |
2000年 | 121篇 |
1999年 | 114篇 |
1998年 | 78篇 |
1997年 | 61篇 |
1996年 | 50篇 |
1995年 | 52篇 |
1994年 | 50篇 |
1993年 | 54篇 |
1992年 | 56篇 |
1991年 | 47篇 |
1990年 | 70篇 |
1989年 | 52篇 |
1988年 | 53篇 |
1987年 | 56篇 |
1986年 | 64篇 |
1985年 | 62篇 |
1984年 | 63篇 |
1983年 | 57篇 |
1982年 | 41篇 |
1981年 | 46篇 |
1980年 | 46篇 |
1979年 | 60篇 |
1978年 | 49篇 |
1976年 | 50篇 |
1975年 | 59篇 |
1974年 | 61篇 |
1973年 | 46篇 |
排序方式: 共有7433条查询结果,搜索用时 15 毫秒
251.
Ability evaluation by proxy: role of maximal performance and related attributes in social comparison
Four experiments tested the effects of information about a proxy's related attributes and maximal effort in social comparisons of ability. In Study 1, a proxy's prior performance at maximal effort exerted systematic effects on participants' personal performance predictions for a novel task. When information about the proxy's effort was ambiguous (Study 2). information about related attribute similarity was used in the formulation of performance predictions. In Studies 3 and 4, 2-way interaction terms revealed that participants used related attribute information in generating performance predictions when the proxy's maximum effort was unknown. However, related attribute information was disregarded when proxy's maximum effort was unambiguous. Results were consistent with the proxy comparison model of ability self-evaluation (L. Wheeler, R. Martin, & J. Suls, 1997). 相似文献
252.
The aim of this investigation was to study the relationships between physical activity, motor ability, and school readiness in 6-yr.-old children. In total, 294 healthy children from Tartu were studied (161 boys and 133 girls). The physical activity of children was reported by parents and teachers using the questionnaire of Harro. The motor ability of children was evaluated using various tests from the Eurofit test battery as well as the 3-min. endurance shuttle run test. The Controlled Drawing Observation rest was used as a predictor of school readiness and development of mental abilities. Indoor physical activities predicted 19-25% of total variance in motor scores for these preschool children. Motor ability tests, which demand children's total attention and concentration, appear related to the chosen measures of school readiness. 相似文献
253.
The present study is concerned with two Slovenian-speaking patients who were asked to produce, in various tasks, verbs, nouns, and adjectives derived by prefixation with prepositions. Despite differences due to their specific linguistic difficulties, both patients' performance was characterized by the differential processing of prefixes and remaining components of complex words. Prepositions in prefixation were mostly preserved, and less frequently substituted, regardless of the numerous errors produced in the remaining portion of the words. These errors seem clearly determined by the morphological structure of the words and therefore appear to be authentic morphological errors. These findings contribute to the theoretical debate on mental lexical representation, speaking in favor of a morphological decomposition in processing of prefixed complex words at different processing levels. 相似文献
254.
The effect of lateral presentation of odours on the hedonic evaluation is reported using a range of different substances. The hypothesis that hedonic evaluation of odours depends on stimulated nostril and on gender and handedness is tested using psychophysical methodology. A total of 51 untrained subjects evaluated 16 substances with different hedonic valences. Each odour substance was presented to the subjects four times, twice at each nostril using a balanced experimental design. Effects of gender and handedness, and interactions, are observed. Some parallels with the perception of visual emotional stimuli are suggested. Hedonic processing of odour stimuli is concluded to be an emotional, rather than an analytical task. 相似文献
255.
256.
We studied the ability of honeybees to discriminate between single odorants and binary olfactory mixtures. We analyzed the effect of the number of common elements between these two stimulus classes on olfactory discrimination. We used olfactory conditioning of the honeybees' proboscis extension reflex (PER), a paradigm in which odors can be associated with a reinforcement of sucrose solution. Bees were asked to discriminate reinforced from nonreinforced olfactory stimuli. They were trained with two elemental odors (A and B) versus a binary olfactory mixture. The mixture was either AB (group 2CE, two common elements), AC (group 1CE, one common element A), or CD (group 0CE, no common element). Three groups followed a positive patterning schedule (mixture reinforced and elements nonreinforced: groups 2CE+, 1CE+, and 0CE+) and three other groups a negative patterning schedule (mixture nonreinforced and elements reinforced: groups 2CE-, 1CE-, and 0CE-). We showed that a reduction of similarity (number of common elements) between elemental odors and compounds enhanced the ability to discriminate elements from compounds and that the kind of compound processing used by the bees supports theories that assume nonelemental compound processing (i.e., that exclude the mere summation of the elemental associative strengths upon compound presentation). 相似文献
257.
This chart review examined the effects of effort on neuropsychological assessment and test performance patterns among genuine and exaggerating patients, with and without neurological findings, as aids to diagnosing symptom exaggeration. The sample consisted of 561 consecutive patients involved in compensation claims. With a flexible neuropsychological test (NPT) battery, the claims were assessed over 2 days. The sample included 303 patients evaluated for traumatic brain injury, 55 patients with neurological disease, and 203 patients assessed for other conditions (eg, depression or chronic pain). An average of 38 ability measures per patient were used to generate an overall NPT domain score. Composite scores were also computed for symptom validity tests, self-report measures of psychiatric symptoms, and memory complaint inventory. Seven NPT cognitive subdomain scores were multiply regressed onto the symptom validity test composite, accounting for 45% of its total variance. Patients were also assigned to Genuine or Exaggerator groups based on symptom validity test performance. The NPT for Exaggerating patients averaged 1.43 standard deviations below that of Genuine patients, suggesting that NPT scores for most Exaggerating patients are underestimates of their true ability. Factor analysis results differed between these groups. As a result, clinicians might avoid falsely identifying genuine patients as exaggerating by incorporating their self-reports of psychiatric symptoms and memory complaints into the diagnostic process. 相似文献
258.
In two experiments, space- and object-based selection effects were investigated, using variants of the ring-cuing paradigm of Egly and Homa (1984). The results revealed significant cuing modulation for nonring configurations of target locations spanning a range of retinal eccentricities, with the cuing effects independent of eccentricity and confined to the configuration of locations (rather than extending to locations within the space enclosed by the cued configuration). These results are consistent with object-based selection operating on a grouped spatial array (Vecera & Farah, 1994). Object selection may be based on a supradimensional saliency map representation of the field, modulated by feature-specific segmentation mechanisms (e.g., an object may be made salient on the basis of its color). Complex objects may be represented by grouped saliency signals. In this way, a two-dimensional spatial (saliency) representation may provide the common format for object-based selection, prior to full object definition. 相似文献
259.
This paper deals with the measurement problem of deriving an overall evaluation of stimuli by n-component bisection. Reflexivity and a generalised form of bisymmetry for two variables will be shown to characterise n-component bisection in terms of quasilinear means, unique up to linear transformations of their generating functions. Copyright 2000 Academic Press. 相似文献
260.
In the present study we made use of Event-Related Potentials (ERPs) to examine raising and subject control constructions in German. Our most salient result is that the ERPs elicited at the empty subject position of a raising construction are clearly different from those elicited at the corresponding position of an otherwise identical subject control construction, the former producing a stronger P600. We argue that this result provides an electrophysiological correlate of the theoretical distinction between NP trace and PRO. 相似文献