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   326篇
  免费   19篇
  2023年   5篇
  2022年   1篇
  2021年   3篇
  2020年   9篇
  2019年   12篇
  2018年   14篇
  2017年   19篇
  2016年   22篇
  2015年   17篇
  2014年   7篇
  2013年   84篇
  2012年   13篇
  2011年   10篇
  2010年   5篇
  2009年   11篇
  2008年   5篇
  2007年   6篇
  2006年   8篇
  2005年   7篇
  2004年   4篇
  2003年   6篇
  2002年   9篇
  2001年   3篇
  2000年   6篇
  1999年   5篇
  1998年   5篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1994年   3篇
  1993年   2篇
  1991年   1篇
  1989年   2篇
  1988年   3篇
  1987年   1篇
  1983年   1篇
  1982年   5篇
  1981年   6篇
  1980年   1篇
  1979年   3篇
  1978年   5篇
  1977年   3篇
  1976年   5篇
  1975年   1篇
  1974年   2篇
排序方式: 共有345条查询结果,搜索用时 15 毫秒
31.
32.
WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.

Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.

Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013.  相似文献   
33.
The established rhetoric of opposition between state and NGOs as development agents has shifted to one of complementarity and common interest. Along with this, the ‘comparative advantage’ claimed for NGOs has expanded from economic and welfare benefits to encompass also the political goods of civil society and popular participation. This paper reviews these developments in the context of Bangladesh. It argues that they need to be assessed critically in ways which are both theoretically informed and locally contextualized. While recognizing that there are, indeed, areas of common experience and interest between the state and NGOs in Bangladesh, it questions whether these necessarily coincide with the interests of those they all invoke: the poor.  相似文献   
34.
Mark J. White 《外交史》1999,23(3):565-570
Book reviewed in this article:
Ernest R. May and Philip D. Zelikow (eds.), The Kennedy Tapes: Inside the White House during the Cuban Missile Crisis  相似文献   
35.
36.
37.
Stable carbon- and nitrogen-isotope ratios were measured for segments along the shafts of hair from eight individuals from the site of Pacatnamu, located in the Jequetepeque Valley on the north coast of Peru. All are from known grave contexts dating from Moche (ca. 450–750 A.D.) to Lambayeque periods (ca. 900–1100 A.D.). The mean δ13C and δ15N values of hair segments from individuals are comparable to those of bone, and demonstrate increased consumption of marine resources in the Lambayeque times relative to the Moche period.  相似文献   
38.
This article highlights a marked growth in the number of second homes in Ireland since the mid-1990s, which is concentrated in the rural and coastal parts of the peripheral Border, Midwest, Southeast, Southwest and West regions, together with parallel growth in the number of long-term vacant dwellings in these regions. These phenomena are linked to economic and population growth, the “laissez faire” nature of land use planning in rural Ireland, the generous fiscal treatment of housing, as well as tax incentives to encourage house building in economically marginal areas. The social and economic impacts of these dwelling on individual localities vary, depending on their number, usage patterns and the nature of the local economy and housing market. However, their environmental consequences are largely negative as is their impact on the national economy and on the economies of those regions where vacant dwellings are concentrated. Thus, our research questions the value of housing-led rural development, as they can result in excessive output of vacant and second homes and highlights the importance of adequately resourcing planning authorities if the worst excesses of rural housing overdevelopment are to be avoided.  相似文献   
39.
40.
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