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191.
In this paper I discuss the clash of values between the Old Order Amish community of Ontario and the dominant social paradigm in agriculture. Land-use and agricultural regulations, designed for an industrial style of agriculture, are experienced as a threat to the survival of the Old Order Amish agricultural social economy and community. The paper describes how I have worked with the Old Order Amish to respond to these challenges and to create public policies that will allow them to maintain their human and agricultural diversity and small-scale sustainable farm practices. Four case studies illuminating the oppressive land-use regulations along with the emancipatory responses to the oppression are examined. The social transformation themes include principles and processes for community psychologists, land-use planners, and community economic development practitioners to consider. The article has heuristic value for a practice-based approach to social change.  相似文献   
192.
Neurofibromatosis, type I (NF-I) is associated with verbal and nonverbal neuropsychological deficits and neuroanatomical anomalies. Few relationships between CNS abnormalities and cognitive function in this population, however, have been found. Reading disabilities and developmental language impairments in the general population have been associated with particular morphologic features in inferior frontal gyrus (IFG) and Heschl's gyrus (HG). We compared the morphology of these regions in children with NF-I and controls. Verbal skills in NF-I were related to IFG morphology, such that individuals with NF-I who showed "typical" gyral patterns in the right hemisphere performed worse across language measures than those showing an extra "atypical" gyrus. A doubling of HG in the left and right hemispheres was also significantly associated with performance on several neuropsychological measures. This is the first study to link regional gyral morphology with language function in NF-I. A possible molecular basis for the observed relationships is discussed.  相似文献   
193.
After overnight abstinence, tobacco smokers smoked an average nicotine yield cigarette and nonsmokers sham smoked an unlit placebo cigarette. EEG alpha(1), delta, and theta frequency amplitudes decreased, whereas alpha(2) and beta frequency amplitude increased. Short, middle (EP) and long latency ERP were also studied in nonsmokers and smokers just after smoking, and after overnight abstinence from tobacco. Short latency potentials were unaffected by tobacco smoking or abstinence. Middle and long-latency potentials were reduced during abstinence and enhanced immediately after tobacco smoking. These findings indicate that compared to nonsmokers smokers have a higher arousal level after smoking than when partially abstinent. Evidence for both normalization from tobacco abstinence as well as stimulation was obtained.  相似文献   
194.
In one experiment, we tested for an association between semantic activation in the right hemisphere (RH) and left hemisphere (LH) and the Aha! experience when people recognize solutions to insight-like problems. The compound remote associate problems used in this experiment sometimes evoke an Aha! experience and sometimes do not. On each trial, participants (N = 44) attempted to solve these problems and, after 7 sec, named a target word, made a solution decision, and rated their insight experience of recognizing the solution. As in prior studies, the participants demonstrated more solution priming for solutions presented to the left visual field-RH (lvf-RH) than for solutions presented to the right visual field-LH (rvf-LH). As was predicted, following unsolved problems the participants showed greater priming for solutions that they rated as evoking an insight experience on the subsequent solution decision than for solutions that did not evoke an insight experience. This association was stronger for solutions presented to the lvf-RH than for those presented to the rvf-LH. These results tie the subjective experience of insight to an objective measure-semantic priming-and suggest that people have an Aha! experience in part because they already had semantic activation that could lead them to recognize the solution quickly. We believe semantic activation in both hemispheres cooperatively contributes to problem solving, but weak solution activation that contributes to the Aha! experience is more likely to occur in the RH than in the LH.  相似文献   
195.
Fear conditioning is a form of associative learning in which subjects come to express defense responses to a neutral conditioned stimulus (CS) that is paired with an aversive unconditioned stimulus (US). Considerable evidence suggests that critical neural changes mediating the CS-US association occur in the lateral nucleus of the amygdala (LA). Further, recent studies show that associative long-term potentiation (LTP) occurs in pathways that transmit the CS to LA, and that drugs that interfere with this LTP also disrupt behavioral fear conditioning when infused into the LA, suggesting that associative LTP in LA might be a mechanism for storing memories of the CS-US association. Here, we develop a detailed cellular hypothesis to explain how neural responses to the CS and US in LA could induce LTP-like changes that store memories during fear conditioning. Specifically, we propose that the CS evokes EPSPs at sensory input synapses onto LA pyramidal neurons, and that the US strongly depolarizes these same LA neurons. This depolarization, in turn, causes calcium influx through NMDA receptors (NMDARs) and also causes the LA neuron to fire action potentials. The action potentials then back-propagate into the dendrites, where they collide with CS-evoked EPSPs, resulting in calcium entry through voltage-gated calcium channels (VGCCs). Although calcium entry through NMDARs is sufficient to induce synaptic changes that support short-term fear memory, calcium entry through both NMDARs and VGCCs is required to initiate the molecular processes that consolidate synaptic changes into a long-term memory.  相似文献   
196.
Blair M  Homa D 《Memory & cognition》2001,29(8):1153-1164
Formal models of categorization make different predictions about the theoretical importance of linear separability. Prior research, most of which has failed to find support for a linear separability constraint on category learning, has been conducted using tasks that involve learning two categories with a small number of members. The present experiment used four categories with three or nine patterns per category that were either linearly separable or not linearly separable. With overall category structure equivalent across category types, the linearly separable categories were found to be easier to learn than the not linearly separable categories. An analysis of individual participants' data showed that there were more participants operating under a linear separability constraint when learning large categories than when learning small ones. Formal modeling showed that an exemplar model could not account for many of these data. These results are taken to support the existence of multiple processes in categorization.  相似文献   
197.
198.
In the present study, we examined alcohol consumption and alcohol problems between managerial and nonmanagerial men and women. We also examined alcohol problems as a function of drinking context (i.e., when they drink and with whom they drink) for each of these four groups. Survey data and data from company records were collected from a large sample of blue and white collar employees (n = 2279). Participants completed a detailed questionnaire aimed at assessing many work-related attitudes, general mental and physical health-related perceptions, motivations for alcohol use, alcohol consumption indices, and alcohol problems. We found that several of the demographic variables differentially predicted alcohol consumption and problems for the four groups. In addition, drinking alone and immediately after work were associated with alcohol problems for women managers at a significantly higher rate than for the other groups of employees. These results support the assertion that more complex models are needed to understand the linkages between work and alcohol use. The research reported in this paper was supported by Grant AA 10690-02, National Institute of Alcohol Abuse and Alcoholism, National Institutes of Health.  相似文献   
199.
We review the recently published report by the Committee on the Prevention of Reading Difficulties in Young Children from a behavior analytic perspective. The authors prescribe what children should learn to be successful readers based on the correlates of reading and the developmental progression of reading errors. The report offers no discussion of theoretical models that can be used by teachers and parents to reform reading instruction or specific procedures that have been shown to be effective at promoting various reading skills. We discuss these omissions in terms of the level of research included in the review, the authors' structural approach to synthesizing this research, and the constructivist orientation common to many early childhood educators. The paper concludes by identifying models and strategies from the behavior analysis literature that can be used to guide instruction and offers a modest suggestion for future reviews of reading research.  相似文献   
200.
The author examines two significant issues, the adjudication of evidence and the architecture of instruction in the context of research on beginning reading. In particular, he reflects on his participation as a member of the National Research Council's committee that published the recent report entitled Preventing Reading Difficulties in Young Children (1998). The National Academy of Sciences panel of experts process is contrasted with a more explicit process for codifying scientific evidence and including quantitative experimental research as the primary source of evidence. In addition, the author argues for the importance of attending to the architecture of instruction in beginning reading.  相似文献   
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