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851.
Hlastala SA Frank E Kowalski J Sherrill JT Tu XM Anderson B Kupfer DJ 《Journal of abnormal psychology》2000,109(4):777-786
A common misconception is that bipolar disorder is an endogenous process. However, previous research suggests a role for life events in the onset of and recovery from bipolar episodes. Yet, there remains some question as to whether the relationship between life events and onset changes over the course of the disorder as a result of the number of episodes an individual has experienced. Using a rigorous interview measure of stressful life events, the current study tested the kindling model (R. M. Post, 1992), which theorizes that major life events play a diminishing role over the course of illness in bipolar patients. Analyses revealed that the number of episodes experienced does not appear to have a significant effect on bipolar 1 patients' reactivity to external stressors. In addition, the results suggest that a more complex relationship exists among age, stress, and onset of new episodes than can be adequately explained by the kindling model. 相似文献
852.
In this paper we investigate first order common knowledge logics; i.e., modal epistemic logics based on first order logic with common knowledge operators. It is shown that even rather weak fragments of first order common knowledge logics are not recursively axiomatizable. This applies, for example, to fragments which allow to reason about names only; that is to say, fragments the first order part of which is based on constant symbols and the equality symbol only. Then formal properties of "quantifying into" epistemic contexts are investigated. The results are illustrated by means of epistemic representations of Nash Equilibria for finite games with mixed strategies. 相似文献
853.
对老年性痴呆治疗研究的反思 总被引:4,自引:0,他引:4
随着世界人口逐年老化,老年性痴呆已成为全球性的社会一医学问题。神经科学及相关学科领域的内的工作者正积极地投入到对Alzheimer病各方面的深入研究,在预防和治疗方面的探索已取得一些阶段性的成果。然而,由于相关基础研究尚无关键性突破,临床治疗始终缺乏有效手段。 相似文献
854.
Gryzunov YA Koplik EV Smolina NV Kopaeva LB Dobretsov GE Sudakov KV 《Stress (Amsterdam, Netherlands)》2006,9(1):53-60
In this study, the hypothesis was tested that behaviour of rats under the open field test condition and effects of subsequent acute stress relate to conformational properties of the main plasma carrier protein, albumin.To evaluate albumin properties, fluorescence intensity of a molecular probe CAPIDAN (N-carboxyphenylimide of dimethylaminonaphthalic acid) at N (at pH 7.4) and F (at pH 4.2) albumin conformations was measured and the N-F signal ratio was calculated. The data obtained showed that CAPIDAN fluoresces selectively from albumin in rat serum and its fluorescence is sensitive to binding of fatty acids and some other ligands to albumin. Behaviour of 78 Wistar male rats was characterized from the fraction of time taken for exploratory and ambulatory activity during the open field test. In rats not subjected to stress (n = 40), a negative correlation was revealed between open field activity and CAPIDAN N-to-F ratio for albumin (r = - 0.55, p < 0.0005). In the group of rats subjected to acute stress (immobilization plus stochastic electrocutaneous stimulation) the correlation between behavioural activity and the albumin conformational properties was significantly positive (r = 0.59, p < 0.0001): the CAPIDAN albumin fluorescence ratio increased in the highly active rats and decreased in the low-activity rats. The mechanisms of the observed effects may involve differences in nonesterified fatty acid production during stress. 相似文献
855.
Ray WJ Odenwald M Neuner F Schauer M Ruf M Wienbruch C Rockstroh B Elbert T 《Psychological science》2006,17(10):825-829
From a neuroscience perspective, little is known about the long-term effect of torture. Dissociative experiences and posttraumatic stress disorder are often the results of this experience. We examined psychological dissociation within a group of 23 torture victims and report its manifestations within neural networks in the human brain. In particular, we observed that dissociative experiences are associated with slow abnormal brain waves generated in left ventrolateral frontal cortex. Given that focal slow waves often result from depriving neural networks of major input, the present results may indicate decoupling of frontal affective processors from left cortical language areas. This interpretation is consistent with the fact that disturbed access to structured verbal memory concerning traumatic events is a core feature of the dissociative experience. 相似文献
856.
在对晚期文艺复兴不同潮流、不同著作地分析中,我们看到一种新的,围绕于君主与基督教的核心历史关系重新解读历史的可能性途径,看到文艺复兴核心概念群的不同组织方式.从而,文艺复兴以一种与"近代起源"拉开了差距的面目呈现出来,它意味着重写历史,尤其是概念史的必要性. 相似文献
857.
Matzel LD Townsend DA Grossman H Han YR Hale G Zappulla M Light K Kolata S 《Neurobiology of learning and memory》2006,86(2):228-240
Across multiple learning tasks (that place different sensory, motor, and information processing demands on the animals), we have found that the performance of mice is commonly regulated by a single factor ("general learning") that accounts for 30-40% of the variance across individuals and tasks. Furthermore, individuals' general learning abilities were highly correlated with their propensity to engage in exploration in an open field, a behavior that is potentially stress-inducing. This relationship between exploration in the open field and general learning abilities suggests the possibility that variations in stress sensitivity/responsivity or related emotional responses might directly influence individuals' general learning abilities. Here, the relationship of sensory/motor skills and stress sensitivity/emotionality to animals' general learning abilities were assessed. Outbred (CD-1) mice were tested in a battery of six learning tasks as well as 21 tests of exploratory behavior, sensory/motor function and fitness, emotionality, and stress reactivity. The performances of individual mice were correlated across six learning tasks, and the performance measures of all learning tasks loaded heavily on a single factor (principal component analysis), accounting for 32% of the variability between animals and tasks. Open field exploration and seven additional exploratory behaviors (including those exhibited in an elevated plus maze) also loaded heavily on this same factor, although general activity, sensory/motor responses, physical characteristics, and direct measures of fear did not. In a separate experiment, serum corticosterone levels of mice were elevated in response to a mild environmental stressor (confinement on an elevated platform). Stress-induced corticosterone levels were correlated with behavioral fear responses, but were unsystematically related to individuals' propensity for exploration. In total, these results suggest that although general learning abilities are strongly related to individuals' propensity for exploration, this relationship is not attributable to variations in sensory/motor function or the individuals' physiological or behavioral sensitivity to conditions that promote stress or fear. 相似文献
858.
Tapp J Ticha R Kryzer E Gustafson M Gunnar MR Symons FJ 《Behavior research methods》2006,38(1):165-169
In this article, we describe the Interval Manager (INTMAN) software system for collecting timesampled observational data and
present a preliminary application comparing the program with a traditional paper-and-pencil method. INTMAN is a computer-assisted
alternative to traditional paper-and-pencil methods for collecting fixed interval time-sampled observational data. The INTMAN
data collection software runs on Pocket PC handheld computers and includes a desktop application for Microsoft Windows that
is used for data analysis. Standard analysis options include modified frequencies, percent of intervals, conditional probabilities,
and kappa agreement matrices and values. INTMAN and a standardized paper-and-pencil method were compared under identical conditions
on five dimensions: setup time, duration of data entry, duration of interobserver agreement calculations, accuracy, and cost.
Overall, the computer-assisted program was a more efficient and accurate data collection system for time-sampled data than
the traditional method. 相似文献
859.
Anxiety sensitivity (AS) has been shown previously to be an important factor in the perception and experience of experimentally induced pain within healthy adults. The aim of the current study was to extend this research by: (i) using the Anxiety Sensitivity Profile (ASP) as an alternative measure of AS; (ii) examining whether different coping instructions affect pain reports; and (iii) investigating potential differences between men and women. Participants were 50 healthy adults (23 males, 27 females) who were required to complete 2 versions of the cold pressor pain task; one version required the use of control instructions, whereas the other made use of acceptance-based instructions. Although the coping instructions were found to affect pain thresholds (acceptance resulted in lower thresholds), a similar pattern of correlations were found between the pain indexes and AS under both conditions. Of the ASP subscales, the gastrointestinal and cognitive concerns components were found to be the most strongly related to pain experiences. When the analysis was conducted separately for each sex, the ASP scales were related to the self-report measures of pain in women, whereas they were related to the behavioural measures of pain in men. These results not only confirm that AS is associated with experimental pain, but that there may be sex differences in this relationship. 相似文献
860.
Differentiating between additive (quantitative) and interactive (qualitative) effects of comorbidity has important treatment implications. This study illustrates the heuristic superiority of a multifactorial approach over simple group comparisons in testing quantitative versus qualitative models of comorbidity. Analysis of variance was used to compare 266 adolescent inpatients identified as depressed, externalizing, both, or neither on self-report measures of personality, school problems, and substance abuse. The results support quantitative rather than qualitative models of comorbidity. Depressed status related most strongly to group differences in interpersonal and self-critical concerns. Externalizing status related most strongly to group differences in school problems and drug use. Main effects for the two statuses together explained especially elevated levels of reactance and alcohol abuse among the comorbid adolescents. 相似文献