首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1401篇
  免费   121篇
  2024年   3篇
  2023年   41篇
  2022年   7篇
  2021年   13篇
  2020年   66篇
  2019年   74篇
  2018年   175篇
  2017年   150篇
  2016年   140篇
  2015年   91篇
  2014年   94篇
  2013年   291篇
  2012年   63篇
  2011年   55篇
  2010年   50篇
  2009年   32篇
  2008年   37篇
  2007年   20篇
  2006年   9篇
  2005年   16篇
  2004年   11篇
  2003年   4篇
  2002年   10篇
  2001年   16篇
  2000年   7篇
  1999年   5篇
  1998年   6篇
  1997年   6篇
  1996年   4篇
  1995年   11篇
  1994年   2篇
  1993年   3篇
  1992年   3篇
  1989年   1篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1982年   2篇
  1979年   1篇
排序方式: 共有1522条查询结果,搜索用时 15 毫秒
991.
992.
Being competitive requires continuously performing product and process innovations nowadays. Because of this reason, the absorption of externally generated R&D is increasingly important for companies. It is well known that companies differ regarding their aptitude for knowledge absorption. This paper aims at the identification of different firm profiles by means of the identification and valuation of drivers that support the absorption of external R&D. For this, we have carried out an empirical work that is based on a random sample of companies located in the northern Spanish county of Biscay. We identify four company conglomerates according to their attitude to absorb externally generated R&D.  相似文献   
993.
ABSTRACT This paper provides an empirical study of the determinants of income inequality across regions of the EU. Using the European Community Household Panel dataset for 102 regions over the period 1995–2000, it analyses how microeconomic changes in human capital distribution affect income inequality for the population as a whole and for normally working people. The different static and dynamic panel data analyses conducted reveal that the relationship between income per capita and income inequality, as well as between a good human capital endowment and income inequality is positive. High levels of inequality in educational attainment are also associated with higher income inequality. The above results are robust to changes in the definition of income distribution and may be interpreted as a sign of the responsiveness of the EU labor market to differences in qualifications and skills. Other results indicate that population ageing, female participation in the labor force, urbanization, agriculture, and industry are negatively associated to income inequality, while unemployment and the presence of a strong financial sector positively affect inequality. Finally, income inequality is lower in social‐democratic welfare states, in Protestant areas, and in regions with Nordic family structures.  相似文献   
994.
995.
The consumption of small prey dates back to the Plio-Pleistocene chronologies in some African sites. However, the systematic acquisition and consumption of small prey in the pre-Upper Palaeolithic times is still a highly debated topic in Europe. Although the utilization of leporids has been recorded in several pre-Late Pleistocene European sites, the evidence of bird consumption is not as common for these periods. Nevertheless, Level XI (MIS 6) of Bolomor Cave has clear diagnostic elements to document the acquisition and use of birds (Aythya sp.) for food in the form of: (1) cutmarks on bones of both the front and hind limb; (2) presence of burning patterns on the extremities of the bones (areas of the skeleton with less meat); and (3) human toothmarks on limb bones. The capture of birds is classified as quick-flying game in the archaeological sites. The acquiring of fast-running (mostly lagomorphs) and quick-flying small prey requires a sophisticated technology and involves obtaining and processing ways different from those used for large- and medium-sized animals. From this perspective, the aim of this paper is to examine possible patterns in the processing sequence of birds from Level XI of Bolomor Cave and to improve the data on their butchery and human consumption in the Middle Pleistocene of Iberian Peninsula.  相似文献   
996.
The extent of racemization of aspartic acid (Asp) – expressed as d/l ratio – has been used as a marker of biomolecular degradation in ancient remains. However, Asp racemization rate is highly variable, and depends on biochemical and geochemical factors. In this paper we aim to determine to which extent the fraction analyzed and the kind of sample used may influence the d/l Asp ratios. Other factors, such as burial site and sample preservation conditions, are also considered.  相似文献   
997.
Skeletal remains of Pazyryk warriors unearthed in a recent archaeological excavation in the Mongolian Altai offer a unique opportunity for verifying ancient histories of warfare and violence given by Herodotus in the fifth century BC. The Pazyryks were Iron Age nomadic groups associated with the eastern Scythians and known from burial site discoveries on the high steppes of the Altai (Central Asia). The aim of this paper is to analyze the evidence for bone trauma provided by the skeletal remains of these Pazyryk warriors with a particular focus on violence-related injuries. The sample consists of 10 individuals, comprising seven adult males, one adult female and two children. Seven individuals exhibited a total of 14 traumatic injuries. Six of these injuries (43%) showed evidence of bone remodelling and eight injuries (57%) were morphologically compatible with a perimortem origin. Twelve injuries (86%) were related to interpersonal violence, most likely caused by weapons similar to those found in Pazyryk tombs (battle-axes, daggers and arrowheads). Five individuals, including the female and one child, exhibited evidence of violent death. Furthermore, one individual also exhibited evidence of scalping. Despite the small number of Pazyryk skeletons analyzed, the pattern of traumatic injuries observed appears to be in agreement with that documented in conflicts related to raids or surprise attacks, and not a result of routinized or ritualized violence. These findings contribute new data to osteological evidence from Scythian burial sites.  相似文献   
998.
This article explores constructions of Spanish masculinity in the first decades of the twentieth century, as Spain engaged in colonialist wars in Morocco; memoirs and literary texts by travellers, soldiers and military leaders such as Francisco Franco and José Millán Astray are read alongside theoretical works. I argue that, like European Orientalism, Spanish Orientalism projects onto Moroccan men an image of fanaticism, barbaric violence and ultra‐virile yet ‘polymorphously perverse’ sexuality. However, that particular image of masculinity is just as often re‐assimilated into a Spanish national identity that can never quite manage to assert its fundamental difference from North Africa.  相似文献   
999.
1000.
Conditional Cash Transfer programmes aim to alleviate short‐term poverty through cash transfers to poor households, and to reduce longer‐term poverty through making these transfers conditional on household investment in the health and education of children. These programmes have become increasingly popular with institutions such as the World Bank. However, the need for conditionalities has been questioned on a number of levels, including its necessity: it has been suggested that the cash transfer in itself may be sufficient to secure most of the programme's wider aims. The example of Nicaragua supports this contention, demonstrating that only a small incentive is needed to bring the desired changes in the uptake of education, since this is something prized by the poor themselves. In health, the Nicaraguan case suggests that demand‐side initiatives might not be as important as supply‐side changes that improve the affordability and accessibility of services. The Nicaragua case also highlights the long‐term limitations of applying such programmes in countries with high levels of poverty and low economic growth. A gendered analysis of the programme highlights the fact that women ‘beneficiaries’ bear the economic and social cost of the programme without apparent benefit to themselves or even necessarily to the household in the short or longer term.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号