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941.
Our primary focus is on analysis of the concept of voluntariness, with a secondary focus on the implications of our analysis for the concept and the requirements of voluntary informed consent. We propose that two necessary and jointly sufficient conditions must be satisfied for an action to be voluntary: intentionality, and substantial freedom from controlling influences. We reject authenticity as a necessary condition of voluntary action, and we note that constraining situations may or may not undermine voluntariness, depending on the circumstances and the psychological capacities of agents. We compare and evaluate several accounts of voluntariness and argue that our view, unlike other treatments in bioethics, is not a value-laden theory. We also discuss the empirical assessment of individuals' perceptions of the degrees of noncontrol and self-control. We propose use of a particular Decision Making Control Instrument. Empirical research using this instrument can provide data that will help establish appropriate policies and procedures for obtaining voluntary consent to research.  相似文献   
942.
In most research on graphics in text students learn the content for a test (e.g., Mayer, 2002). The present study examined whether one of the principles from that literature, namely the deleterious effect of extraneous graphic information, would apply to adults who were consulting a leaflet to answer questions. The study used a mixed factorial design with 48 participants from three age bands (young-adult, young-old, old-old). Participants used two leaflets to answer questions, one without graphics and the other with either extraneous embellishing or supportive explanatory graphics. Relative to leaflets without graphics, the old-old participants were significantly slower finding information when leaflets contained embellishing but not explanatory graphics. The graphics had no effect on the other age groups. These findings suggest that either the reading task or the thematic relevance of the extraneous graphics may limit their negative effects for most adults but that negative effects recur for older readers.  相似文献   
943.
Despite extensive research, the role of phonological short-term memory (STM) during oral sentence comprehension remains unclear. We tested the hypothesis that phonological STM is involved in phonological analysis stages of the incoming words, but not in sentence comprehension per se. We compared phonological STM capacity and processing times for natural sentences and sentences containing phonetically ambiguous words. The sentences were presented for an auditory sentence anomaly judgement task and processing times for each word were measured. STM was measured via nonword and word immediate serial recall tasks, indexing phonological and lexicosemantic STM capacity, respectively. Significantly increased processing times were observed for phonetically ambiguous words, relative to natural stimuli in same sentence positions. Phonological STM capacity correlated with the size of this phonetic ambiguity effect. However, phonological STM capacity did not correlate with measures of later semantic integration processes while lexicosemantic STM did. This study suggests that phonological STM is associated with phonological analysis processes during sentence processing.  相似文献   
944.
A variety of visual mental imagery tasks have been shown to activate regions of visual cortex that subserve the perception of visual events. Here fMRI was used to examine whether imagery‐related visuocortical activity is modulated if imagery content is held constant but there is a change in the memory retrieval strategy used to invoke imagery. Participants were scanned while visualising common objects in two different conditions: (a) recalling recently encoded pictures and (b) based on their knowledge of concrete nouns. Results showed that retrieval‐related activations in frontal cortex were bilateral when pictures were visualised but left‐lateralised when nouns were visualised. In posterior brain regions, both imagery conditions led to activation in the same set of circumscribed areas in left temporal‐parietal cortex, including a region of the left fusiform gyrus that has previously been implicated in visual imagery. These findings suggest that the posterior network activated during imagery did not vary with strategic task‐related changes in the frontal network used to retrieve imagery content from memory.  相似文献   
945.
In overimitation, an observer reproduces a model's visually causally redundant actions in pursuit of an object-directed outcome. There remains an assumption that costs involved in adopting redundant actions renders them maladaptive in the immediate context. Here, we report on an experiment designed to evaluate whether or not overimitating is costly in this way. One hundred and eight children from two contrasting cultural groups (Australian Western vs. South African Bushman) observed an adult open an apparatus using a process that locked one side and opened another. Two toys were then inserted in the locked side and one in the open side. Copying the model meant access only to the lower quantity reward would be possible. This process was repeated for a second trial. Contrary to expectation, children retrieved similar numbers of toys regardless of whether they reproduced the model's actions or not, suggesting that in contexts like that presented here, overimitation is not costly in the ways commonly assumed.  相似文献   
946.
Avner de Shalit wants cities to have their own immigration policies. On a radical reading, this would transfer control over immigrant admissions from states to cities. But can cities choose the immigrants they prefer on economic or cultural grounds, or does this discriminate unfairly against those judged to be less desirable? I argue that de Shalit fails to apply the luck egalitarian principle consistently when discussing immigrant admissions. I also claim that there is a tension between seeing cities as the bearers of distinct cultural ethoses, and therefore as bulwarks against the homogenising effects of globalization, and disbarring them from carrying out culturally selective immigration policies. De Shalit’s own preferred model of the immigrant-friendly city – Amsterdam – appears to lack any distinct ethos, other than an ethos of welcome and cultural blending. Moreover, democratic states also have a legitimate interest in controlling immigration. They must be concerned about the consequences for social justice of admitting migrants and the political effects that follow when the migrants become citizens themselves. They must also consider the environmental impacts of population growth. Cities should play a major role in integrating immigrants, but not in admitting them.  相似文献   
947.
We examined time perspective and self-esteem in adolescents, young adults, middle-aged adults, and older adults. Time perspective was measured with scales that assess relative orientations and relationships among the past, present, and future. Age effects were examined with standard analytic strategies to determine categorical differences between age groups and with new statistical techniques designed to show continuous age patterns. Findings indicated that (1) thinking about the future was greatest for adolescents and young adults and lowest for middle-aged and older adults, and thinking about the present increased across ages; (2) fewer adolescents and middle-aged participants perceived that the time periods were interrelated compared to younger and older adults; and (3) across ages, a greater emphasis towards the past compared to other time periods was associated with lower self-esteem, whereas emphasizing the present and the future jointly was associated with higher self-esteem.  相似文献   
948.
949.
This investigation compared the neural correlates of inhibition in normal older adults (OAs) and OAs with mild cognitive impairment (MCI). It was hypothesized the MCI group would require a greater amount of resources for inhibition, and therefore display greater functional activation in specific regions of interest (ROIs). Twenty-six OAs without and 17 with MCI completed the Stroop task during functional neuroimaging, and completed additional out-of-scanner neuropsychological measures. During inhibition, there were minimal functional Magnetic Resonance Imaging (fMRI) differences found between groups in a priori specified ROIs and with post-hoc multiple regression analyses. However, these minimal differences did not survive corrected thresholds. Robust differences were found with several tasks of a neuropsychological screening battery. The results of this study suggest only very minimal group differences in fMRI activation during inhibition which may not reliably identify MCI, and this condition may be best detected by traditional neuropsychological techniques.  相似文献   
950.
Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD.  相似文献   
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