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991.
992.
Recent memory theory has emphasized the concept ofneed probability—that is, the probability that a given piece of learned information will be tested at some point in the future. It has been proposed that, in real-world situations, need probability declines over time and that the memory-loss rate is calibrated to match the progressive reduction in need probability (J. R. Anderson & Schooler, 1991). The present experiments were designed to examine the influence of the slope of the need-probability curve on the slope of the retention curve. On each of several trials, subjects memorized a list of digits, then retained the digits in memory for 1, 2, 4, 8, or 16 sec. Some trials ended with a recall test; other trials ended with the message, “no test.” In Experiment 1, the likelihood of encountering a memory test (i.e., the need probability) was made to either increase or decrease as the retention interval increased; in Experiment 2, need probability either was flat (invariant across retention intervals) or decreased as the retention interval increased. The results indicated that the shape of the need-probability curve influenced the slope of the retention curve (Experiment 1) and that the effect became larger as the experimental session progressed (Experiment 2). The findings support the notion that memory adapts to need probabilities and that the rate of forgetting is influenced by the slope of the need-probability curve. In addition, all of the forgetting curves approximated a power function, suggesting that need probability influences the slope but not the form of forgetting. 相似文献
993.
994.
Wesley D. Allan Javad H. Kashani Julie Dahlmeier Payam Taghizadeh John C. Reid 《Journal of abnormal child psychology》1997,25(6):465-473
The purpose of the current study was to examine the psychometric properties and clinical utility of the Scale for Suicide Ideation (SSI) for children. The SSI was administered to 100 children who were hospitalized. Data were not used from 13 subjects due to the presence of a psychotic disorder or IQ less than 70, leaving 87 participants. The SSI was examined regarding its internal consistency, concurrent validity, construct validity, and factor structure when used with children. Based on the findings, the SSI appears to have adequate psychometric properties and can be used by clinicians and researchers examining children in an inpatient setting. Recommendations for clinicians are included to help make the SSI more functional in use for children. 相似文献
995.
Shari B. Wasserstein Nadja Lopez Donald K. Routh 《Journal of abnormal child psychology》1997,25(1):1-5
This issue, redesigned in a new format, marks the beginning of Volume 25, the beginning of the silver anniversary year of the Journal of Abnormal Child Psychology. Data were compiled from the first 24 volumes to study changes over time, and Pearson correlations were calculated to determine linear trends in the journal's development The number of articles per volume has doubled, from about 25 to 50. In recent years the first authors of articles were more likely to be located outside the U.S. (up from about 5% to about 25%). Also, in recent years the first authors of articles were less likely to be affiliated with nonmedical school university departments and more likely to be affiliated with medical schools or research institutes. An introduction to this special 25th anniversary issue is provided. 相似文献
996.
Craig R. Colder John E. Lochman Karen C. Wells 《Journal of abnormal child psychology》1997,25(3):251-263
Parenting practices have been previously linked to childhood symptomatology. However, little consideration has been given to the potential effect of individual differences within the child on this relation. The current study assessed the moderating effects of children's activity level and fear on relations between parenting practices and childhood aggression and depressive symptoms using a sample of 64 fourth-, and fifth-grade boys. The findings showed that poorly monitored active boys and fearful boys who were exposed to harsh discipline exhibited high levels of aggression. Boys characterized by high fear who were exposed to harsh discipline or whose parents were extremely overinvolved showed elevated levels of depressive symptoms. These findings suggest that integrating children's individual differences with parenting models enhances our understanding of the etiology of childhood symptomatology. The intervention implications of such an integration are discussed. 相似文献
997.
In this target article the following hypotheses are discussed: (1) Colour is autonomous: a perceptuolinguistic and behavioural universal. (2) It is completely described by three independent attributes: hue, brightness, and saturation: (3) Phenomenologically and psychophysically there are four unique hues: red, green, blue, and yellow; (4) The unique hues are underpinned by two opponent psychophysical and/or neuronal channels: red/green, blue/yellow. The relevant literature is reviewed. We conclude: (i) Psychophysics and neurophysiology fail to set nontrivial constraints on colour categorization. (ii) Linguistic evidence provides no grounds for the universality of basic colour categories. (iii) Neither the opponent hues red/green, blue/yellow nor hue, brightness, and saturation are intrinsic to a universal concept of colour. (iv) Colour is not autonomous. 相似文献
998.
MJ Stillman B Shukitt-Hale BP Coffey A Levy HR Lieberman 《Stress (Amsterdam, Netherlands)》1997,1(4):191-200
Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences. 相似文献
999.
Engel JD Kane G Jones DL Lynn-McHale D Swartz M Durbin P Klingen D 《The Journal of medical humanities》1997,18(3):193-208
This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs. 相似文献
1000.
Stobo J 《Kennedy Institute of Ethics journal》1997,7(4):387-389
Health care professionals should be the ones to make allocation decisions in the managed care setting because they are in the best position to assess outcomes, cost effectiveness, and quality of care. 相似文献