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951.
One way to increase choice of healthy over unhealthy behaviors is to increase the cost of less healthy alternatives or reduce the cost of healthier alternatives. The influence of price on purchases of healthy and unhealthy foods was evaluated in two laboratory experiments. In Experiment 1, thirty-two 10- to 12-year-old youth were given $5.00 and allowed to purchase multiple portions of a healthy food (fruit or vegetable) and a less healthy food (higher-fat snack). The price of one type of food varied from $0.50 to $2.50, while the price of the other type was held at $1.00. Increasing the price of a type of food reduced purchases of that type of food, but did not lead to substitution with the alternative type of food. In Experiment 2, twenty 10- to 14-year-old youth were given $1.00, $3.00, and $5.00 to purchase healthy and unhealthy foods. The price of each food was raised and lowered by 25% and 50%. Raising the price of healthy or unhealthy foods resulted in decreased purchases of those foods, and income available interacted with price to predict the pattern of substitution of alternative foods. These results show the potential for controlled laboratory studies of price and food purchases, and show that the substitution of healthier for unhealthy food is related to available money.  相似文献   
952.
Disoriented 4-year-old children use a distinctive container to locate a hidden object, but do they reorient by this information? We addressed this question by testing children's search for objects in a circular room containing one distinctive and two identical containers. Children's search patterns provided evidence that the distinctive container served as a direct cue to a hidden object's location, but not as a directional signal guiding reorientation. The findings suggest that disoriented children's search behavior depends on two distinct processes: a modular reorientation process attuned to the geometry of the surface layout and an associative process linking landmarks to specific locations.  相似文献   
953.
In a repeated testing paradigm, list items receiving item-specific processing are more likely to be recovered across successive tests (item gains), whereas items receiving relational processing are likely to be forgotten progressively less on successive tests. Moreover, analysis of cumulative-recall curves has shown that item-specific processing produces a slower, but steadier rate of recall than relational processing. The authors relied on these findings to determine the type of processing that both list items and critical lures receive in the Deese-Roediger-McDermott false memory procedure. The first 2 experiments revealed that critical lures produced more item gains, but only the list items resulted in a decrease in item losses across successive tests. The critical lures also produced slower but steadier cumulative recall. In Experiments 3 and 4, the critical items were physically presented during study, which resulted in the lures producing progressively fewer losses across successive tests. The authors concluded that critical items receive more item-specific processing than list items but that unless they are presented in the list, they do not become part of participants' organized retrieval scheme.  相似文献   
954.
Forty mothers whose preterm infants were about to be discharged from the Neonatal Intermediate Care Nursery (NICU) were randomly assigned to two groups: the first group of mothers conducted preterm infant massage and the second group only observed their preterm infants receiving massage. Both groups of mothers had lower depressed mood scores following the session. However, only the group who massaged their infants had lower anxiety scores after the session.  相似文献   
955.
This paper investigates the ability of infants to attend to continuous stimulus variables and how this capacity relates to the representation of number. We examined the change in area needed by 6-month-old infants to detect a difference in the size of a single element (Elmo face). Infants successfully discriminated a 1:4, 1:3 and 1:2 change in the area of the Elmo face but failed to discriminate a 2:3 change. In addition, the novelty preference was linearly related to the ratio difference between the novel and familiar area. Results suggest that Weber's Law holds for area discriminations in infancy and also reveal that at 6 months of age infants are equally sensitive to number, time and area.  相似文献   
956.
Visuospatial learning and memory impairments are an early marker for age-related cognitive decline and Alzheimer's disease. Similar to humans, aged dogs show visuospatial learning and memory deficits (). One hundred and nine beagle dogs ranging between 0.25 and 11.99 years were tested on a visuospatial delayed non-matching to position (DNMP) task to better characterize the progression of visuospatial deficits in the dog. Age predicted 48.2% of the variability in learning the DNMP, with dogs ranging from 1 to 11.99 years generally making more errors with increasing age. By contrast, puppies (<1 year) likely were showing developmental deficits, possibly due to an immature prefrontal cortex. Mild visuospatial deficits were detected by 6 years, which precedes the typical onset of amyloid-beta (Abeta) accumulation in the dog brain by two years, and can serve as an early marker for cognitive decline in the dog. These findings suggest that (1) age-related changes in visuospatial function in the dog models that seen in humans, further validating the dog as a model for human aging and dementia; and (2) other mechanisms, such as oxidative stress, soluble Abeta oligomers or cholinergic deficits, are likely contributing to the early impairment.  相似文献   
957.
The report from President George W. Bush’s New Freedom Commission on Mental Health (NFC), Achieving the Promise: Transforming Mental Health Care in America(2003), proposes goals and recommendations for improving mental health services. This report has significant implications for the delivery of mental health services through the schools. A focused discussion of the potential opportunities and challenges of implementing NFC recommendations related to school-based mental health is presented. Strategies for addressing five key areas at the intersection of school mental health and the Commission’s recommendations include: stigma reduction, suicide prevention, expansion and improvement of school mental health, and screening and treatment of co-occurring mental health and substance abuse disorders.  相似文献   
958.
Prior research (DeLoache, Uttal & Rosengren, 2004) has documented that 18- to 30-month-olds occasionally make scale errors: they attempt to fit their bodies into or onto miniature objects (e.g. a chair) that are far too small for them. The current study explores whether scale errors are limited to actions that directly involve the child's body. We investigated whether children would also make scale errors with a doll and objects that were much too small for the doll (e.g. a chair, a bed). Many participants did try to fit the doll into or onto the miniature objects. Thus, the previously documented phenomenon of scale errors extends to situations in which the relevant size difference is between two objects. This finding supports the view that scale errors occur when visual information about object size fails to influence the decision to act on an object. The results are discussed in terms of the use of visual information for the planning and control of actions.  相似文献   
959.
We present the results of two experiments that probe the ability of rhesus macaques to match visual arrays based on number. Three monkeys were first trained on a delayed match-to-sample paradigm (DMTS) to match stimuli on the basis of number and ignore continuous dimensions such as element size, cumulative surface area, and density. Monkeys were then tested in a numerical bisection experiment that required them to indicate whether a sample numerosity was closer to a small or large anchor value. Results indicated that, for two sets of anchor values with the same ratio, the probability of choosing the larger anchor value systematically increased with the sample number and the psychometric functions superimposed. A second experiment employed a numerical DMTS task in which the choice values contained an exact numerical match to the sample and a distracter that varied in number. Both accuracy and reaction time were modulated by the ratio between the correct numerical match and the distracter, as predicted by Weber's Law.  相似文献   
960.
  • This paper describes a study in the psychology of market mavenism, the consumer tendency to become especially involved in the marketplace. The purpose was to investigate empirically associations with the important consumer characteristics of innovativeness, status consumption, and need for uniqueness. The findings support the notion that market mavenism is due less to the demographic characteristics of consumers as it is more a socially constructed phenomenon. Global innovativeness, status consumption, and creative choice counterconformity explained more variance in market mavenism than did demographics. Theoretically, these findings enrich our knowledge of the psychology of market mavens by suggesting some motivations for their behavior. Practically, marketing strategies can be fine‐tuned to appeal more effectively to this important segment of consumers by appealing to mavens' willingness to try new things, to their need for uniqueness, and to their willingness to seek social status through consumption.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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