全文获取类型
收费全文 | 3286篇 |
免费 | 14篇 |
专业分类
教育 | 2302篇 |
科学研究 | 553篇 |
各国文化 | 6篇 |
体育 | 101篇 |
综合类 | 7篇 |
文化理论 | 72篇 |
信息传播 | 259篇 |
出版年
2023年 | 2篇 |
2022年 | 11篇 |
2021年 | 31篇 |
2020年 | 19篇 |
2019年 | 26篇 |
2018年 | 86篇 |
2017年 | 124篇 |
2016年 | 191篇 |
2015年 | 128篇 |
2014年 | 80篇 |
2013年 | 144篇 |
2012年 | 167篇 |
2011年 | 178篇 |
2010年 | 91篇 |
2009年 | 45篇 |
2008年 | 74篇 |
2007年 | 65篇 |
2006年 | 58篇 |
2005年 | 689篇 |
2004年 | 472篇 |
2003年 | 302篇 |
2002年 | 138篇 |
2001年 | 66篇 |
2000年 | 35篇 |
1999年 | 25篇 |
1998年 | 7篇 |
1997年 | 6篇 |
1996年 | 9篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1985年 | 2篇 |
1976年 | 2篇 |
1973年 | 1篇 |
1830年 | 2篇 |
排序方式: 共有3300条查询结果,搜索用时 15 毫秒
891.
Studies addressing the connections between knowledge and organization structures can be divided into two classes. One class holds that a perspective on knowledge signals shortcomings of classical design principles and calls for flatter hierarchy and less specification of the production structure. Another class maintains that a knowledge perspective on organizations is at odds with any design perspective, whether classical or not, because the emergent, thoroughly social and practice-based nature of knowledge as knowing in action makes knowledge a useless and even dangerous beacon to designers: ex ante, knowledge is said to be fundamentally indeterminate and any attempt to ‘structure around knowledge’ may effectively drive out knowledge. To explore differences and possible bridges between these two calls of studies, the paper explores how both elements of the equation, organization structure and organizational knowledge, are to be conceived to ensure a meaningful connection between them. It is argued that the grouping focus in both defines the meeting place of organization structures and organizational knowledge, but shows that the involved knowledge and grouping concepts are not mutually compatible. It leads to a view where organization structures are seen as the ‘seeding’ background for knowledge integration processes that, in turn, constitute the patterns of work relationships envisioned in the designer's organizational decomposition and grouping. For illustration purposes, the paper presents the example of the Max Planck Institute that describes one possible way through the conceptual model presented in the paper. 相似文献
892.
Dra?an Butorac Ivana ?elap Sanja Ka?kov Vera Robi? Tomislav Mileti? Zlata Flegar Me?tri? Andrea Hulina Krunoslav Kuna Tihana ?ani? Grubi?i? Marija Grdi? Rajkovi? 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(2):273-280
Introduction
Postmenopausal women have higher risk of cardiovascular disease. One of the contributing factors could be reduced activity of anti-atherogenic enzyme paraoxonase 1 (PON1). The aim of this study was to examine differences in the lipid status, paraoxonase and arylesterase PON1 activities and PON1 phenotype in women with regular menstrual cycle and in postmenopausal women.Materials and methods:
The study included 51 women in reproductive age (25 in follicular and 26 in luteal phase of the menstrual cycle) and 23 women in postmenopause. Lipid parameters in sera were determined using original reagents and according to manufacturer protocol. PON1 activity in serum was assessed by spectrophotometric method with substrates: paraoxon and phenylacetate. PON1 phenotype was determined by double substrate method.Results:
Compared to the women in follicular and luteal phase, postmenopausal women have significantly higher concentration of triglyceride [0.9 (0.7–1.3), 0.7 (0.6–1.0) vs. 1.5 (0.9–1.7) mmol/L; P = 0.002], cholesterol [5.10 (4.78–6.10), 5.05 (4.70–5.40) vs. 6.30 (5.73–7.23) mmol/L; P < 0.001], LDL [3.00 (2.56–3.63), 3.00 (2.70–3.70) vs. 3.90 (3.23–4.50) mmol/L; P < 0.001], and apolipoprotein B [0.88 (0.75–1.00), 0.79 (0.68–1.00) vs. 1.07 (0.90–1.24) mmol/L; P = 0.002]. PON1 basal [104 (66–260), 106 (63–250) vs. 93 (71–165) U/L; P = 0.847] and salt-stimulated paraoxonase activity [210 (131–462), 211 (120–442) vs. 180 (139–296) U/L; P = 0.857] as well as arylesterase activity [74 (63–82), 70 (54–91) vs. 70 (60–81) kU/L; P = 0.906] and PON1 phenotype (P = 0.810) were not different in the study groups.Conclusion:
There are no differences in PON1 activity and PON1 phenotype between women with regular menstrual cycle and postmenopausal women. 相似文献893.
There is extensive coverage in literature of knowledge management (KM) implementation based on private sector entities. Although recent trends have been characterised by a shift towards understanding KM in the public sector organisations, there is very little focus on the public sector entities in Africa. KM has become popular in modern organisations because it is capable of enhancing the effectiveness and efficiency of entities if properly implemented. While the explosion of the internet has seen the emergence of public sector transformation programmes such as e-government plans, most African states have wholly adopted these without due consideration to the structural constraints they would face in their implementation. Having observed that e-government is technology-based and most African states lack the necessary information technology (IT) tools to effectively implement it, my proposition in this paper is that the most viable option of transforming the public sector in Africa could be through KM, rather than e-government. Nevertheless, e-government plans in African states should be implemented as a component of the overall KM strategy. 相似文献
894.
We analyse how the impact of determinants of inter-firm knowledge transfers in alliances can be moderated by the proximity of the resources pooled by partners. Six factors are examined: relative absorptive capacity (RAC), inter-partner trust, cultural distance between allies, knowledge ambiguity, knowledge protection, and the partners’ learning intent. We distinguish alliances mobilizing similar resources by partners (called ‘endogamies’ as allies build on their similarities) from alliances pooling different resources (called ‘exogamies’ as allies build on their differences). We propose that: (a) the impact of RAC on knowledge transfers is reinforced in exogamies, but reduced in endogamies; (b) the knowledge ambiguity and cultural distance effect is less in endogamies than in exogamies; (c) the trust and knowledge protection impact is stronger in exogamies than in endogamies; (d) the learning intent impact on knowledge transfers is similar in endogamies and exogamies. 相似文献
895.
Inter-organizational knowledge sharing systems (IOKSS) can serve as strategic systems for knowledge-based sectors. Most prior research on inter-organizational systems (IOSs) focuses on organizations’ adoption of such systems; they reveal little about knowledge workers’ adoption of IOS, especially in horizontally linked firms. Knowledge workers’ perception is critical to the deployment of IOKSS at all stages. On the basis of a Delphi technique in the health sector, this study demonstrates that IOKSS can benefit individuals, customers, organizations, the sector, and the knowledge sharing process, and that the challenges of IOKSS arise from individuals, peers, IOKSS, organizations, and the sector. 相似文献
896.
Frauke Gr?ter 《中国科学院院刊(英文版)》2014,(2):195-197
<正>The Group on Protein Mechanics and Evolution at the CAS-MPG Partner Institute for Computational Biology,Shanghai,was established in January 2007 and headed by Dr.Frauke Gr?ter.The Klaus Tschira Lab has continued the eff orts of this former Independent Junior Research Group,since Dr.Gr?ter took up a position at the Heidelberg Institute of Theoretical Studies(HITS)in Heidelberg,Germany,in 相似文献
897.
Harisha Ramachandraiah Sahar Ardabili Asim M. Faridi Jesper Gantelius Jacob M. Kowalewski Gustaf M?rtensson Aman Russom 《Biomicrofluidics》2014,8(3)
Passive particle focusing based on inertial microfluidics was recently introduced as a
high-throughput alternative to active focusing methods that require an external force field to
manipulate particles. In inertial microfluidics, dominant inertial forces cause particles to move
across streamlines and occupy equilibrium positions along the faces of walls in flows through
straight micro channels. In this study, we systematically analyzed the addition of secondary Dean
forces by introducing curvature and show how randomly distributed particles entering a simple
u-shaped curved channel are focused to a fixed lateral position exiting the curvature. We found the
lateral particle focusing position to be fixed and largely independent of radius of curvature and
whether particles entering the curvature are pre-focused (at equilibrium) or randomly distributed.
Unlike focusing in straight channels, where focusing typically is limited to channel cross-sections
in the range of particle size to create single focusing point, we report here particle focusing in a
large cross-section area (channel aspect ratio 1:10). Furthermore, we describe a simple u-shaped
curved channel, with single inlet and four outlets, for filtration applications. We demonstrate
continuous focusing and filtration of 10 μm particles (with >90% filtration
efficiency) from a suspension mixture at throughputs several orders of magnitude higher than flow
through straight channels (volume flow rate of 4.25 ml/min). Finally, as an example of high
throughput cell processing application, white blood cells were continuously processed with a
filtration efficiency of 78% with maintained high viability. We expect the study will aid in the
fundamental understanding of flow through curved channels and open the door for the development of a
whole set of bio-analytical applications. 相似文献
898.
Jaka Lindi?Author VitaePeter BalohAuthor Vitae Vincent M. RibièreAuthor Vitae 《International Journal of Information Management》2011,31(2):183-188
Organizations must innovate if they are to survive in today's fiercely competitive marketplace. In this paper, we explore how leading organizations are using emerging technologies to enable novel forms of ideation that can radically increase the sheer volume of ideas they explore. In addition, we outline how organizations use technologies to cost effectively manage this increased volume of ideas by optimizing generation, mobilization, advocacy and screening, experimentation, commercialization, and even the diffusion and implementation of ideas. Critical to this is the management of knowledge during the innovation process. 相似文献
899.
900.