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991.
992.
Ambient white noise (80 dB), compared with quiet (52-dB) testing conditions, improved the performance of elderly and younger subjects on simple addition. Reliable age-related interactions were found on health measures of systolic and diastolic blood pressure, as well as heart rate. Heightened sensory conditions reduced the physiological measures of arousal in the younger group, whereas significant cardiovascular reactivity was found among the older group. The results are suggestive of the potential for increased cardiovascular risk as a function of sensory stimulation in the elderly despite improvements on cognitive tasks. Additional research is needed to evaluate the multidimensional effects of extended sensory stimulation on the elderly.  相似文献   
993.
Previous work on investor decision making has focused almost exclusively on information specific to the company being judged. Consequently, every decision is viewed as a novel event, disconnected from the investor's existing knowledge. In this study, the analogical reasoning literature provides the theoretical support for arguing that investors frequently utilize existing knowledge as a basis for generating predictions about a company's future. The specific proposal is that investors transfer their existing knowledge via two different forms of analogical reasoning. The first, relational reasoning, is based primarily on structural correspondence between a novel company and an existing schema. The second, literal similarity reasoning, is based primarily on surface correspondence of a novel company and a previously encountered company. Our theoretical framework is tested in a study in which experienced investors predict the outcome of a novel company's strategy after reading about the experiences of other companies who implemented a similar strategy. The results are consistent with the occurrence of both relational and literal similarity reasoning, with relational reasoning emerging as the dominant approach to generating investors' predictions. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
994.
为考察初中生友谊质量与孤独感的变化轨迹及两者间的关系,采用关系网络问卷、孤独感量表对西安市的875名初中生(M=12.73±0.18;男生494名)进行三年追踪测量,使用多元潜变量增长模型进行分析。结果发现:(1)初中三年,中学生的友谊质量逐渐提高,孤独感水平逐渐下降;(2)初一时的友谊质量和孤独感水平存在显著的个体差异,初中三年期间二者的发展速度也存在个体差异;(3)初一时的友谊质量可显著预测初一时的孤独感水平(β=-1.77,p<0.001)及随后的发展速度(β=0.20,p<0.05);(4)男生的孤独感水平初始值高于女生,友谊质量的初始值则低于女生;高SES个体孤独感的起始值高于低SES个体。本研究结果揭示了初中三年期间个体友谊质量与孤独感的动态变化关系及友谊质量对孤独感的预测作用,对改善青少年孤独感的现状有一定的现实指导意义。  相似文献   
995.

Anxiety and depressive disorders are global public health concerns, and research suggests that these disorders are common in parents and can adversely influence family functioning. However, little is known about normative levels of anxiety and depressive symptoms in parents of school-age children. The present study reports on generalized anxiety and depressive symptoms in 1570 parents and guardians of a nationally representative sample of children ages five to twelve years using two widely used and validated questionnaires: the eight-item variant of the Patient Health Questionnaire depression scale (PHQ-8) and the seven-item Generalized Anxiety Disorder scale (GAD-7). Moderate to severe levels of generalized anxiety symptoms were reported in 12.7% of the total sample and moderate to severe levels of depressive symptoms were reported in 14.1% of the sample; 17.7% of the sample reported moderate to severe levels of either generalized anxiety or depressive symptoms. This percentage was higher for females, younger parents and guardians, and parents and guardians reporting lower household incomes. These data, collected online in early 2018, may be useful for researchers and clinicians studying and treating anxiety and depression in parents. Further, these data provide a baseline for researchers currently studying the impact of changes related to the novel coronavirus (COVID-19) pandemic (e.g., school closures) on the mental health of parents of school-age children.

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996.
Reliance on self‐report limits clinicians' ability to accurately predict suicidal behavior. In this study the predictive validity of an objective measure, the death/suicide Implicit Association Test (d/sIAT), was tested among psychiatrically hospitalized veterans. Following acute stabilization, 176 participants completed the d/sIAT and traditional suicide risk assessments. Participants had similar d/sIAT scores regardless of whether they had recently attempted suicide. However, d/sIAT scores significantly predicted suicide attempts during the 6‐month follow‐up above and beyond other known risk factors for suicidal behavior (OR = 1.89; 95% CI: 1.15–3.12; based on 1SD increase). The d/sIAT may augment the accuracy of suicide risk assessment.  相似文献   
997.
Research has investigated how sleep affects emotional memory and how emotion enhances visual processing, but these questions are typically asked by re-presenting an emotional stimulus at retrieval. For the first time, we investigate whether sleep affects neural activity during retrieval when the memory cue is a neutral context that was previously presented with either emotional or nonemotional content during encoding. Participants encoded scenes composed of a negative or neutral object on a neutral background either in the morning (preceding 12 hours awake; wake group) or evening (preceding 12 hours including a night of sleep; sleep group). At retrieval, participants viewed the backgrounds without their objects, distinguishing new backgrounds from those previously studied. Occipital activity was greater within the sleep group than the wake group specifically during the successful retrieval of neutral backgrounds that had been studied with negative (but not neutral) objects. Moreover, there was enhanced connectivity between the middle occipital gyrus and hippocampus following sleep. Within the sleep group, the percentage of REM sleep obtained correlated with activity in the middle occipital gyrus, lingual gyrus, and cuneus during the successful retrieval of neutral backgrounds previously paired with negative objects. These results confirm that emotion affects neural activity during retrieval even when the cues themselves are neutral, and demonstrate, for the first time, that this residual effect of emotion on visual activity is greater after sleep and may be maximized by REM sleep.  相似文献   
998.
Across three experiments, we explore differences between relational categories—whose members share common relational patterns—and entity categories, whose members share common intrinsic properties. Specifically, we test the claim that relational concepts are more semantically mutable in context, and therefore less stable in memory, than entity concepts. We compared memory for entity nouns and relational nouns, tested either in the same context as at encoding or in a different context. We found that (a) participants show better recognition accuracy for entity nouns than for relational nouns, and (b) recognition of relational nouns is more impaired by a change in context than is recognition of entity nouns. We replicated these findings even when controlling for factors highly correlated with relationality, such as abstractness–concreteness. This suggests that the contextual mutability of relational concepts is due to the core semantic property of conveying relational structure and not simply to accompanying characteristics such as abstractness. We note parallels with the distinction between nouns and verbs and suggest implications for lexical and conceptual structure. Finally, we relate these patterns to proposals that a deep distinction exists between words with an essentially referential function and those with a predicate function.  相似文献   
999.
This paper describes the relations of psychological distress with 11 ecological factors (5 community, 4 family, and 2 individual) among 423 older urban adolescents who are predominantly people of color. Data were obtained by means of self-report via group-administered questionnaires given between 1994 and 1996; most scales are multi-item. There is wide variation in distress. There are very few statistically significant relationships between the ecological factors and distress, and those are negligible. Girls whose parents have less education and live in extended families have higher distress; family and individual domains are correlated .04 and .03 with distress and the community domain .00, so this ecological model accounts for a mere 7%, of the common total variance in distress.  相似文献   
1000.
Daniel Callahan's concept of a sustainable medicine is examined by looking at experiences Old Order Amish communities have had with organ and bone marrow transplantation. The Amish possess many characteristics that might make them embrace limits on the use of expensive, life-prolonging medical treatments: they believe that the good of the individual should be subordinated to the good of the community, they are suspicious of progress as a goal, and they are more comfortable with dying than many other modern Americans. However, the Amish actively pursue these treatments without the benefit of private or government insurance. Although the Amish affective response to sick individuals is worthy of emulating, their commitment to help individuals obtain and pay for transplants has had negative financial and cultural effects on some Amish communities. The Amish experience can thus teach us lessons about how to care for one another when we are sick and dying, but it can also teach us how difficult but important it is to limit some forms of expensive care for the good of our communities.  相似文献   
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