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1.
It was examined whether cooperative learning within the Success for All (SfA) program led to improved group work behaviour of Grade 1 pupils. 168 pupils of six SfA schools and 144 pupils of four control schools participated. Positive and negative group work behaviour was observed during a group task, taking into account socioemotional ethos, group participation, and type of dialogue. Longitudinal multilevel analysis was used for the sequence of observed 20-s time intervals. SfA groups showed more positive and less negative group work behaviour compared to control groups, whilst controlling for several group characteristics. Results suggest that negative group work behaviour increased gradually during the whole task in control groups, while in SfA groups it increased only towards the end of the task. The findings indicate that cooperative learning may lead to improved group work behaviour of young pupils (6–7 years old).  相似文献   
2.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
3.
Recently, models that based on Transformer (Vaswani et al., 2017) have yielded superior results in many sequence modeling tasks. The ability of Transformer to capture long-range dependencies and interactions makes it possible to apply it in the field of portfolio management (PM). However, the built-in quadratic complexity of the Transformer prevents its direct application to the PM task. To solve this problem, in this paper, we propose a deep reinforcement learning-based PM framework called LSRE-CAAN, with two important components: a long sequence representations extractor and a cross-asset attention network. Direct Policy Gradient is used to solve the sequential decision problem in the PM process. We conduct numerical experiments in three aspects using four different cryptocurrency datasets, and the empirical results show that our framework is more effective than both traditional and state-of-the-art (SOTA) online portfolio strategies, achieving a 6x return on the best dataset. In terms of risk metrics, our framework has an average volatility risk of 0.46 and an average maximum drawdown risk of 0.27 across the four datasets, both of which are lower than the vast majority of SOTA strategies. In addition, while the vast majority of SOTA strategies maintain a poor turnover rate of approximately greater than 50% on average, our framework enjoys a relatively low turnover rate on all datasets, efficiency analysis illustrates that our framework no longer has the quadratic dependency limitation.  相似文献   
4.
本文通过在CNKI数据库中搜索了来源期刊为《科技管理研究》(2003-2016.9)的相关文献,运用科学计量分析方法,对其现状和研究热点进行了分析。研究发现,技术创新、影响因素、知识产权、产业集聚、指标体系、科技创新等都是近年来研究的热门话题。  相似文献   
5.
The rapid development of e-commerce is driving many traditional manufacturing enterprises to establish online channels. This typically leads to online and offline channel conflicts for these enterprises. Existing studies on channel conflict management primarily focus on describing the conflicts and discussing the types of strategies. Utilizing the case study method and taking the resource orchestration perspective as the theoretical lens, this study examines the implementation processes of online and offline channel integration and segmentation strategies in two Chinese manufacturing enterprises. The findings reveal the prerequisite to select online and offline integration and segmentation strategies, and specific resource orchestration actions and capabilities generated under the guidance of the integration and segmentation strategies. This study has theoretical implications to the online and offline channel conflict management strategies by extending the “what” question to the “how” question. In addition, this study also provides references to practitioners for selecting and implementing appropriate online and offline channel conflict management strategies.  相似文献   
6.
Majority opinions are often observed in the process of social interaction in online communities, but few studies have addressed this issue with empirical data. To identify an appropriate theoretical lens for explaining majority opinions in online environments, this study investigates the skewness statistic, which indicates how many “Likes” are skewed to major comments on a Facebook post; 3489 posts are gathered from the New York Times Facebook page for 100 days. Results show that time is not an influential factor for skewness increase, but the number of comments has a logarithmic relation to skewness increase. Regression models and Chow tests show that this relationship differs depending on topic contents, but majority opinions are significant in overall. These results suggest that the bandwagon effect due to social affordance can be a suitable mechanism for explaining majority opinion formation in an online environment and that majority opinions in online communities can be misperceived due to overestimation.  相似文献   
7.
冯泽  陈凯华  戴小勇 《科研管理》2019,40(10):73-86
现有关税收优惠政策对企业创新活动影响的文献缺乏从整个创新链的全角度揭示税收优惠政策是否真正提高企业创新能力的探索。基于中关村科技型企业数据,本文选取税收优惠政策中典型的政策工具“研发费用加计扣除”作为研究对象,有别于已有主要从“投入”视角关注研发费用加计扣除引导作用的研究,从“投入-产出-收益”的创新链全视角,将创新过程分为技术研发阶段与技术转化阶段,以揭示研发费用加计扣除政策是否真的提升了企业创新能力。基于PSM-DID方法的实证研究结果发现:在投入端,研发费用加计扣除政策显著提高了企业的研发投入规模与强度;在产出端,研发费用加计扣除政策仅促进了研发产出规模的提升,而对于产出强度则无显著影响;在收益端,研发费用加计扣除对收益规模与强度同样有显著的促进作用。本文的发现肯定了我国研发费用加计扣除政策的引导作用,以及其在企业创新能力提升中发挥的积极作用。本文的研究思路为揭示政府创新激励政策的效果提供了新视角,研究发现为从创新链与企业创新能力的角度思考和改善政府研发税收优惠政策的管理和实施提供了新证据。  相似文献   
8.
外部网络关系对企业双元创新的影响结果存在较大争议,企业维持何种状态的外部网络关系会促进双元创新,影响机理中知识吸收能力起到怎样的作用,这是亟需研究的问题。对387家企业为样本进行问卷调查,运用结构方程模型法,以知识获取能力和知识实现能力为双重中介,探析外部网络关系对企业双元创新的影响。研究结果表明:外部网络关系不同维度对双元创新具有差异化影响;网络关系强度和网络关系密度的提高以及网络关系深度的适度降低有利于渐进性创新,网络关系深度和网络关系密度的提高以及网络关系强度的适度降低更有利于突破性创新;知识吸收能力在外部网络关系对双元创新的影响中发挥部分中介作用。  相似文献   
9.
With greater access to computational resources, people use search to address many everyday challenges in their lives, including solving technology problems. Although there are now many useful ‘how-to’ resources online (especially videos on YouTube), it can still be difficult to identify, understand, and resolve certain kinds of technical problem. While research tasks have been studied for many years and we know the tactics people use, we know far less about searchers’ tactics for how-to technical tasks that involve actually being able to apply found information to resolve a problem. Crucial to our study was developing and studying a highly realistic, how-to technical task, for which there was no single guidance resource: making a phone safe for a child. After providing 39 participants with an actual phone to fix, and a search engine to perform the task, we analysed their search tactics using retrospective cued think aloud interviews. Our primary contribution is a set of 77 tactics used, in three categories, along with detail of how common they were. We conclude that people had a lot of tactics in their repertoire. Although it was not hard for participants to find relevant information, what was hard was for participants to find information they could use; indeed only 23% of participants successfully completed the entire task. Domain knowledge affected the choice of tactics used (although not necessarily towards better task success). We discuss these influences and make design recommendations for how future search systems can support those in resolving how-to technical tasks.  相似文献   
10.
BackgroundThe current state of knowledge regarding the role of non-offending fathers in supporting their sexually abused children is very scarce.ObjectiveThe objective of this study is to further our understanding of fathers’ roles following disclosure of their children’s sexual abuse (SA) by evaluating fathers’ perceptions of the impact of disclosure on their involvement and support of their children.Participants and methodThis qualitative study relies on individual semi-structured interviews conducted with 17 fathers of allegedly abused children.ResultsInductive thematic analysis first highlighted that some reported a period of disengagement from the child during which they put into question their role and attitudes, followed by a period of re-involvement. This period of difficulties experienced by some fathers in regard to their involvement towards their children was due to either their own important psychological distress, their ambivalence towards their child or even because of feelings of uneasiness experienced during physical contact with them. Despite this, findings indicate the presence of thoughts and attitudes that suggest children are a source of concern for fathers. The four forms of abuse-specific support previously observed among mothers (believing the child, seeking out professional services, protecting him/her from the offender, supporting him/her emotionally) were also observed among fathers. In accordance with the activation theory, a form of support specific to fathers, namely, encouraging the child to open up to and explore the world outside the family, thereby, fostering the child’s self-esteem development, was observed and constitutes a relevant finding.ConclusionClinical and empirical implications are discussed.  相似文献   
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