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981.
This article reports investigations of inferences that depend both on connectives between clauses, such as or else, and on relations between entities, such as in the same place as. Participants made more valid inferences from biconditionals—for instance, Ann is taller than Beth if and only if Beth is taller than Cath—than from exclusive disjunctions (Exp. 1). They made more valid transitive inferences from a biconditional when a categorical premise affirmed rather than denied one of its clauses, but they made more valid transitive inferences from an exclusive disjunction when a categorical premise denied rather than affirmed one of its clauses (Exp. 2). From exclusive disjunctions, such as Either Ann is not in the same place as Beth or else Beth is not in the same place as Cath, individuals tended to infer that all three individuals could be in different places, whereas in fact this was impossible (Exps. 3a and 3b). The theory of mental models predicts all of these results.  相似文献   
982.
While grammatical aspects of language are preserved, executive deficits are prominent in Lewy body spectrum disorder (LBSD), including Parkinson’s disease (PD), Parkinson’s dementia (PDD) and dementia with Lewy bodies (DLB). We examined executive control during sentence processing in LBSD by assessing temporary structural ambiguities. Using an on-line word detection procedure, patients heard sentences with a syntactic structure that has high-compatibility or low-compatibility with the main verb’s statistically preferred syntactic structure, and half of the sentences were lengthened strategically between the onset of the ambiguity and its resolution. We found selectively slowed processing of lengthened ambiguous sentences in the PDD/DLB subgroup. This correlated with impairments on measures of executive control. Regression analyses related the working memory deficit during ambiguous sentence processing to significant cortical thinning in frontal and parietal regions. These findings emphasize the role of prefrontal disease in the executive limitations that interfere with processing ambiguous sentences in LBSD.  相似文献   
983.
Reliable Digit Span (RDS) is a heavily researched symptom validity test with a recent literature review yielding more than 20 studies ranging in dates from 1994 to 2011. Unfortunately, limitations within some of the research minimize clinical generalizability. This systematic review and cross-validation study was conducted to address these limitations, thus increasing the measure's clinical utility. Sensitivity and specificity rates were calculated for the ≤6 and ≤7 cutoffs when data were globally combined and divided by clinical groups. The cross-validation of specific diagnostic groups was consistent with the data reported in the literature. Overall, caution should be used when utilizing the ≤7 cutoff in all clinical groups and when utilizing the ≤6 cutoff in the following groups: cerebrovascular accident, severe memory disorders, mental retardation, borderline intellectual functioning, and English as a second language. Additional limitations and cautions are provided.  相似文献   
984.
The event-related potential (ERP) effect of mismatch negativity (MMN) was the first electrophysiological probe to evaluate cognitive processing (change detection) in newborn infants. Initial studies of MMN predicted clinical utility for this measure in identification of infants at risk for developmental cognitive deficits. These predictions have not been realized. We hypothesized that in sleeping newborn infants, measures derived from wavelet assessment of power in the MMN paradigm would be more robust markers of the brain's response to stimulus change than the ERP-derived MMN. Consistent with this premise, we found increased power in response to unpredictable and infrequent tones compared to frequent tones. These increases were present at multiple locations on the scalp over a range of latencies and frequencies and occurred even in the absence of an ERP-derived MMN. There were two predominant effects. First, theta band power was elevated at middle and late latencies (200 to 600 ms), suggesting that neocortical theta rhythms that subserve working memory in adults are present at birth. Second, late latency (500 ms) increased power to the unpredictable and infrequent tones was observed in the beta and gamma bands, suggesting that oscillations involved in adult cognition are also present in the neonate. These findings support the expectation that frequency dependent measures, such as wavelet power, will improve the prospects for a clinically useful test of cortical function early in the postnatal period.  相似文献   
985.
Despite the importance of scientific integrity to the well-being of society, recent findings suggest that training and mentoring in the responsible conduct of research are not very reliable or effective inhibitors of research misbehavior. Understanding how and why individual scientists decide to behave in ways that conform to or violate norms and standards of research is essential to the development of more effective training programs and the creation of more supportive environments. Scholars in business management, psychology, and other disciplines have identified many important factors that affect ethical behavior, including individual, contextual, and organizational factors. Surprisingly little research has been conducted to examine the role of these factors in either the development of ethical decision-making skills, or their applicability to ethical issues commonly encountered in research and other scholarly and professional activities. Interdisciplinary approaches combined with research and discipline relevant paradigms should greatly enhance understanding of the individual contextual and organizational factors involved in ethical and unethical research conduct. Such studies will inform and facilitate the development of more effective ethics education programs in the sciences and engineering professions.  相似文献   
986.
To explore the influence of circadian rhythms on executive function during early adolescence, we administered a battery of executive function measures (including a Go-Nogo task, the Iowa Gambling Task, a Self-ordered Pointing task, and an Intra/Extradimensional Shift task) to Morning-preference and Evening-preference participants (N = 80) between the ages of 11 and 14 years who were tested in the morning or afternoon. Significant Chronotype × Time of Day interactions (controlling for amount of sleep the previous night) revealed that adolescents tested at their optimal times of day performed better than those tested at their nonoptimal times. Implications for our understanding of physiological arousal, sleep, and executive function during adolescence are discussed.  相似文献   
987.
Leisure-time physical activity (LTPA) represents an important factor contributing to the development and management of osteoporosis yet research linking LTPA with perceived health markers has been limited in this cohort. The purpose of this study was to test the relationship between LTPA and perceived health controlling for select demographic factors and chronic conditions in people living with osteoporosis. Population-health survey data from cycle 2.2 of the Canadian Community Health Survey were used in conjunction with linear multiple regression models. Participants were 1538 (n female = 1371) adults who reported living with osteoporosis. Demographic factors, chronic conditions, and more frequent participation in LTPA accounted for variance in diverse indices representing perceived health. LTPA was the only predictor to account for unique variance in each marker of perceived health. Overall, it would appear that increased use of LTPA as an adjunct to therapeutic interventions may be a viable aid to enhancing self-perceived health amongst Canadians living with osteoporosis.  相似文献   
988.
Evidence is mixed regarding an independent association between anxiety and suicidality in youth. Study 1 examined suicidal ideation in treatment-referred, anxiety-disordered youth (N = 312, aged 7-17). Forty-one percent of anxiety-disordered youth endorsed suicidal ideation. Anxiety disorder severity, global impairment, and current depressive symptoms predicted suicidal ideation in a multivariate model. Study 2 compared youth (N = 216, aged 7-14) with and without anxiety disorders. Higher rates of suicidal ideation were associated with anxiety diagnosis, and levels of anxiety predicted suicidal ideation after controlling for comorbid depressive disorders, current depressive symptoms, and global impairment. Results support an association between anxiety disorders and suicidal ideation in treatment-referred youth and recommend routine screening for suicidal ideation in this population.  相似文献   
989.
The authors examined the relationship of perceived stress, specific types of coping resources, the working alliance, and the supervisory working alliance among 232 counselor supervisees. The working alliance and the supervisory working alliance were negatively related to perceived stress and positively related to multiple coping resources. Two regression models for predicting the working alliance and supervisory working alliance from perceived stress and specific coping resources were significant. Implications for practice and research are discussed.  相似文献   
990.
Time flies when you're having fun, but what is it about pleasant experiences that makes time seem to go by faster? In the experiments reported here, we tested the proposal that approach motivation causes perceptual shortening of time during pleasant experiences. Relative to a neutral state or a positive state with low approach motivation (Experiment 1), a positive state with high approach motivation shortened perceptions of time. Also, individual differences in approach motivation predicted shorter perceptions of time. In Experiment 2, we manipulated approach motivation independently of the affective state and showed that increasing approach motivation caused time to be perceived as passing more quickly. In Experiment 3, we showed that positive approach motivation, as opposed to arousal, shortens perception of time by comparing a highly arousing positive state with a highly arousing negative state. Shortening of time perception in appetitive states may prolong approach-motivated behavior and increase the likelihood of acquiring appetitive objects or goals.  相似文献   
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