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   285篇
  免费   41篇
  326篇
  2024年   2篇
  2023年   1篇
  2020年   4篇
  2019年   4篇
  2018年   10篇
  2017年   22篇
  2016年   22篇
  2015年   3篇
  2014年   16篇
  2013年   74篇
  2012年   44篇
  2011年   50篇
  2010年   31篇
  2009年   3篇
  2008年   3篇
  2007年   3篇
  2006年   1篇
  2005年   3篇
  2004年   5篇
  2003年   2篇
  2002年   2篇
  2001年   4篇
  2000年   3篇
  1999年   1篇
  1996年   2篇
  1992年   2篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1981年   1篇
  1980年   1篇
  1972年   1篇
排序方式: 共有326条查询结果,搜索用时 15 毫秒
61.
62.
The goal of this paper is to assess the variation in the proportional contribution of diverse resources to the diet of human populations from northwest Patagonia (Argentina) throughout the Middle-Late Holocene. Particularly, we assessed the variation among three geographic areas and two periods. We first estimated the expected proportions of terrestrial animals and plants and aquatic resources for each area according to the Binford’s frames of references approach. A Bayesian mixing method was then applied to calculate the proportion of plants and animals in the diets from stable isotopes (δ13C and δ15N) of human bone collagen. The isotope values suggest that the composition of diets differed spatially and temporally. Diets of South Mendoza were mainly composed of terrestrial animals (Rhea-Lama and rodents) with a greater incorporation of C3 plants towards the later Late Holocene; in North Neuquén, Rhea and Lama represent a proportion of 0.84 of the diet consumed; and finally, the sample of Center Neuquén is the only one with high values of Araucaria in the diet. The isotopic values obtained for the three studied areas did not fit to the expectations of Binford’s model, North Neuquén being the area that departs most from the predicted proportions of terrestrial animals and plants and aquatic organisms in the diet. These findings open up new questions about the local conditions that influenced regional variation in the diet of prehistoric hunter-gatherers.  相似文献   
63.
64.
Sorrowful Eyes     
  相似文献   
65.
    
Agriculture has recently been the subject of considerable research and policy attention. Events such as the 2008 ‘world food price crisis’ and concerns over the future of global food security have led to calls for a ‘New Green Revolution’, with an emphasis on boosting yields through new transgenic crop varieties. However, critics have raised concerns over the growing role of global agribusiness and transnational capital in agriculture, as well as the potential social and ecological impacts of new technologies. An analysis of emerging agricultural trends thus demands a framework that is able to negotiate the complex multi‐scalar interplay between environmental, technological, scientific, political and economic factors. In this paper, we focus on the potential contribution of a synthesis between political ecology and Actor–Network Theory to our understanding of agricultural networks. We review the literature with a view to teasing out key insights and sketching out future research priorities. We focus on questions surrounding power and agency, the political ecology of scale and the role of situated knowledges and practices.  相似文献   
66.
    
ABSTRACT This study investigates the determinants of interregional migration flows in Italy in the light of the upsurge occurred in 1996, after two decades of decreasing internal migration rates. The fixed‐effect vector decomposition estimator (FEVD) is applied to a gravity model using bilateral migration flows for the period 1996–2005. It is shown that the FEVD improves the estimates with respect to the traditional panel data estimators. The GDP per capita and the unemployment rate appear to be the key determinants whose changes push migrants out from their regions and direct them to “better off” destinations. Migrants leaving the regions in the Center‐North respond differently to the push and pull forces compared to southern migrants. The dynamic model provides evidence for the presence of social networks, which in this analysis take place for each pair of regions.  相似文献   
67.
In the Edwardian period, the essays, novels, and criticism of G.K. Chesterton gave voice to a unique but emblematic form of patriotic anti-imperialism. The article places his views in the context of the Liberal Little Englander reaction to the Boer War, and offers two comparative case studies. The first focuses on Chesterton's inheritance of the late-Victorian anti-imperialist rhetoric of William Morris; the second assesses his fraught relationship with internationalism, as represented in the writings of Morris's political collaborator, E.B. Bax. Chesterton's radical populist patriotism, it turns out, had more in common with contemporary socialist ideologies than the currently prevailing view of its parochialism would allow.  相似文献   
68.
    
  相似文献   
69.
    
  相似文献   
70.
    
Sept cavaliers quittèrent la Ville au crépuscule, face au soleil couchant, par la porte de l'ouest qui n'etait plus guardée. Tête haute, sans se cacher, au contraire de tous ceux qui avaient abandonné la Ville, car ils ne fuyaient pas, ils ne trahissaient rien, espéraient moins encore et se gardaient d'imaginer. Ainsi étaient-ils armés, le coeur et l'âme désencombrés scintillant froidement comme du cristal, pour le voyage qui les attendait. Sur l'ordre du margrave héréditaire, simplement, ils allaient, ils s'étaient mis en mouvement et le plus jeune d'entre eux, qui n'avait pas seize ans, fredonnait une chanson…  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