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231.
The HIV-1 transgenic (Tg) rat model is valuable for understanding HIV-associated neurocognitive disorders (HAND) and accompanying substance use and misuse. Tg and F344/NHsd wildtype (WT) rats were allowed to self-administer intrajugular cocaine. For the first 7 sessions, neither genotype self-administered cocaine (0.1 mg/kg/infusion) on a fixed ratio 1 schedule. We thus implemented a lever–cocaine “autoshaping” session followed by a series of manipulations changing dose and reinforcement schedule. Tg rats self-administered much less cocaine than WT rats throughout the study. Of 8 Tg rats, 5 modestly increased self-administration from sessions 36–50. Of those, only 3 showed a lever discrimination. Of 10 WT rats, 8 acquired robust self-administration by session 19; all WT rats self-administered cocaine by the end of the study. WT and Tg rats had similar baseline locomotor activity in the self-administration chamber suggesting that the low levels of cocaine intake in the Tg rats did not reflect a nonspecific motor impairment in this rat strain. Concomitant measurement of activity with self-administration revealed activity increases that followed increased cocaine intake. That relation held in Tg rats. Therefore, the present study provides evidence that HIV-1 Tg rats are less sensitive to the reinforcing effects of cocaine than their F344 WT counterparts.  相似文献   
232.
Most studies have considered the effects of particular characteristics on academic achievement individually, which means that little is known about how they function together. Using the population-based Minnesota Twin Family Study, the authors investigated the effects of child academic engagement (interest, involvement, effort), IQ, depression, externalizing behavior, and family environmental risk on academic achievement (reported school grades) from ages 11 through 17. Hierarchical linear growth curve modeling showed main effects on initial reported Grades for all variables, and IQ mitigated the deleterious effects of family risk and externalizing. Only engagement affected change in Grades through adolescence. Influences on initial Grades were strongly genetically influenced, associated primarily with IQ, engagement, and externalizing behavior. Shared environmental influences on initial Grades linked engagement, IQ, and family risk. Genetic influences on change in Grades were substantial, but they were not associated with the academic, family risk, and mental health covarying factors. These results indicate that age 11 achievement and change in achievement through adolescence show systematic patterns and document the existence of individual differences in the commonly shared developmental experience of adapting to the school environment.  相似文献   
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234.
Functional MRI (fMRI) was used to examine the relationship between processing of pleasant and unpleasant stimuli and activity in prefrontal cortex. Twenty volunteers identified the colors in which pleasant, neutral, and unpleasant words were printed. Pleasant words prompted more activity bilaterally in dorsolateral prefrontal cortex (DLPFC) than did unpleasant words. In addition, pleasant words prompted more activity in left than in right DLPFC. Response speed to pleasant words was correlated with DLPFC activity. These data directly link positive affect, enhanced performance, and prefrontal activity, providing some of the first fMRI evidence supporting models of emotional valence and frontal brain asymmetry based on electroencephalography (EEG).  相似文献   
235.
We investigate whether two-digit numbers are decomposed for purposes of numerical comparison (e.g., choosing the larger one). Earlier theorists concluded that numbers are processed holistically (Brysbaert, 1995; Dehaene, Dupoux, & Mehler, 1990), or that holistic and decomposed processes operate in parallel (Nuerk, Weger, & Willmes, 2001). In the present experiment, we presented pairs of two-digit numbers with a decade distance of either zero (e.g., 54-57) or one (54-61). If a holistic process contributes to two-digit comparison, there should be an overall distance effect for number pairs with a decade distance of one. On the other hand, if numbers are decomposed and a holistic comparison does not contribute, this overall distance effect should be absent for these number pairs. Evidence is found that, at least in the present task settings, numbers are not compared holistically. The results are interpreted in terms of a recently proposed theory of numerical cognition (Verguts & Fias, 2004; Verguts, Fias, & Stevens, in press).  相似文献   
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Articles in the journal of Addictions and Offender Counseling between 1979 and 1998 were analyzed according to authors' demographic characteristics and article content to provide a historical review of the addictions and offender counseling field. Study results, historical trends, and future implications are presented.  相似文献   
238.
Self‐efficacy has been shown to be a robust predictor of exercise and other health‐related behaviors (e.g., Bandura, 1986, 1995, 1997; Godin, Desharnais, Valois, & Bradet, 1995; Maddux, 1995; McAuley, Wraith, & Duncan, 1991). Maddux has proposed that there are different types of self‐efficacy and that these types may fulfill different roles in the motivation of behavior, perhaps based on characteristics of the target behavior. The purpose of this study was to examine 3 different types of self‐efficacy: task, coping, and scheduling and their respective usefulness in distinguishing among persons reporting different levels of exercise involvement. A cross‐sectional telephone survey using exercise behavior as the selection criterion was completed with 203 adults. Results showed that coping and scheduling efficacy were the best disciminators of level of exercise behavior. Task efficacy did not clearly distinguish between exercise groups. The theoretical and applied implications are discussed, particularly noting specific targets for future intervention.  相似文献   
239.
Previous research has shown that trait anger is associated with biases in attention and interpretation, but the temporal relation between these two types of biases remains unresolved. Indeed, two very different models can be derived from the literature. One model proposes that interpretation biases emerge from earlier biases in attention, whereas the other model proposes that hostile interpretations occur quickly, even prior to the allocation of attention to specific cues. Within the context of integrated visual scenes of ambiguously intended harm, the two models make opposite predictions that can be examined using an eye-tracking methodology. The present study (N = 45) therefore tracked participants’ allocation of attention to hostile and non-hostile cues in ambiguous visual scenes, and found support for the idea that high anger individuals make early hostile interpretations prior to encoding hostile and non-hostiles cues. The data are important in understanding associations between trait anger and cognitive biases.  相似文献   
240.
There is currently a void in the literature regarding the kinds of support women find most beneficial when dealing with a spouse’s sexually addictive or compulsive behaviors. Addressing this void is particularly relevant for clergy, seeing as they are increasingly sought out as an initial and/or primary support for dealing with this marital issue. Using grounded theory methodology, 22 women from Canada and the USA were interviewed to find out what they found most helpful as they sought support to cope with a spouse’s sexually addictive and compulsive behaviors. Insights for pastoral counselors and clergy were highlighted.  相似文献   
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