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   7529篇
  免费   170篇
  7699篇
  2020年   97篇
  2019年   175篇
  2018年   194篇
  2017年   239篇
  2016年   221篇
  2015年   182篇
  2014年   165篇
  2013年   2166篇
  2012年   206篇
  2011年   186篇
  2010年   251篇
  2009年   233篇
  2008年   166篇
  2007年   170篇
  2006年   156篇
  2005年   105篇
  2004年   109篇
  2003年   109篇
  2002年   120篇
  2001年   116篇
  2000年   96篇
  1999年   100篇
  1998年   110篇
  1997年   95篇
  1996年   80篇
  1995年   75篇
  1994年   75篇
  1993年   69篇
  1992年   69篇
  1991年   64篇
  1990年   49篇
  1989年   54篇
  1988年   65篇
  1987年   73篇
  1986年   53篇
  1985年   77篇
  1984年   80篇
  1983年   81篇
  1982年   60篇
  1981年   74篇
  1980年   70篇
  1979年   71篇
  1978年   52篇
  1977年   73篇
  1976年   60篇
  1975年   54篇
  1974年   47篇
  1973年   34篇
  1972年   37篇
  1970年   35篇
排序方式: 共有7699条查询结果,搜索用时 0 毫秒
31.
32.
The collection and analysis of 3D digital data is a rapidly growing field in archaeology, anthropology, and forensics. Even though the 3D scanning of human remains in archaeology has been conducted for over 10 years, it is still frequently considered as a new field. Despite this, the availability of 3D scanning equipment and the number of studies employing these methods are increasing rapidly, and it is arguably damaging to the validity of this field to continue to consider these methods new and therefore not subject to the same standardisations as other researches. This paper considers the current issues regarding the lack of standardisation in the methods, ethics, and ownership of 3D digital data with a focus on human remains research. The aim of this paper is to stimulate further research and discussion, allowing this field to develop, improving the quality and value of future research.  相似文献   
33.
34.
This paper examines the discourse of autism as we have experienced it as parents of an autistic six year‐old girl. Because both authors are anthropologists, we were professionally trained to understand something of what discourses are and do. However, our training did not necessarily help us blunt the original force of the diagnosis. Over time we have come to understand both our daughter and the discourse that is said to define her differently, and these understandings have fed back into our understanding of our discipline. One key transformative event occurred when we took our family to live in a village where we had done previous research. This reminded us of the conceptual power of discourses: we put the discourse of autism to work for our own purposes, but at the same time it works on us, shapes us in ways we do not always realize.  相似文献   
35.
36.
37.
A holistic landscape approach to cultural resource analysis of a set of archaeological sites in the central Penobscot Valley led to inferences regarding the Holocene physical and biological environmental context. Targeted environmental studies include (1) examination of forest and wetland changes through time and (2) lake-level studies as a key to paleohydrology. These studies were combined with broad-scale geomorphic investigations and detailed stratigraphic analyses, and studies of archaeological sites and their artifact assemblages. Together, these studies provide a picture of dramatic changes to the physical and vegetational landscape. These included reestablishment of a major river following deglaciation, evolution of extensive lakes to uplands and peatlands, and a shifting mosaic of open and closed forest composed of a variety of hardwood and softwood species. Inferences based on buried soils exposed in archaeological excavations supported climatic interpretations based on vegetation and paleohydrology. As a result, this work allowed evaluation of (1) site formation and preservation processes and (2) occupational patterns. Site formation and preservation of Early Holocene sites can be linked to sedimentation by hydraulic damming upstream of rapids at the mouths of tributary streams. Shifting human land use reflected by changes in occupation patterns appears to correspond to changes in forest composition as well as wetland and stream evolution through time.  相似文献   
38.
39.
40.
Poropat, S.F., Nair, J.P., Syme, C.E., Mannion, P.D., Upchurch, P., Hocknull, S.A., Cook, A.G., Tischler, T.R. &; Holland, T. XX.XXXX. 2017. Reappraisal of Austrosaurus mckillopi Longman, 1933 Longman, H.A., 1933. A new dinosaur from the Queensland Cretaceous. Memoirs of the Queensland Museum 10, 131144. [Google Scholar] from the Allaru Mudstone of Queensland, Australia’s first named Cretaceous sauropod dinosaur. Alcheringa 41, 543–580. ISSN 0311-5518

Austrosaurus mckillopi was the first Cretaceous sauropod reported from Australia, and the first Cretaceous dinosaur reported from Queensland (northeast Australia). This sauropod taxon was established on the basis of several fragmentary presacral vertebrae (QM F2316) derived from the uppermost Lower Cretaceous (upper Albian) Allaru Mudstone, at a locality situated 77 km west-northwest of Richmond, Queensland. Prior to its rediscovery in 2014, the type site was considered lost after failed attempts to relocate it in the 1970s. Excavations at the site in 2014 and 2015 led to the recovery of several partial dorsal ribs and fragments of presacral vertebrae, all of which clearly pertained to a single sauropod dinosaur. The discovery of new material of the type individual of Austrosaurus mckillopi, in tandem with a reassessment of the material collected in the 1930s, has facilitated the rearticulation of the specimen. The resultant vertebral series comprises six presacral vertebrae—the posteriormost cervical and five anteriormost dorsals—in association with five left dorsal ribs and one right one. The fragmentary nature of the type specimen has historically hindered assessments of the phylogenetic affinities of Austrosaurus, as has the fact that these evaluations were often based on a subset of the type material. The reappraisal of the type series of Austrosaurus presented herein, on the basis of both external morphology and internal morphology visualized through CT data, validates it as a diagnostic titanosauriform taxon, tentatively placed in Somphospondyli, and characterized by the possession of an accessory lateral pneumatic foramen on dorsal vertebra I (a feature that appears to be autapomorphic) and by the presence of a robust ventral mid-line ridge on the centra of dorsal vertebrae I and II. The interpretation of the anteriormost preserved vertebra in Austrosaurus as a posterior cervical has also prompted the re-evaluation of an isolated, partial, posterior cervical vertebra (QM F6142, the ‘Hughenden sauropod’) from the upper Albian Toolebuc Formation (which underlies the Allaru Mudstone). Although this vertebra preserves an apparent unique character of its own (a spinopostzygapophyseal lamina fossa), it is not able to be referred unequivocally to Austrosaurus and is retained as Titanosauriformes indet. Austrosaurus mckillopi is one of the oldest known sauropods from the Australian Cretaceous based on skeletal remains and potentially provides phylogenetic and/or palaeobiogeographic context for later taxa such as Wintonotitan wattsi, Diamantinasaurus matildae and Savannasaurus elliottorum.

Stephen F. Poropat* [; ] Department of Chemistry and Biotechnology, Swinburne University of Technology, John St, Hawthorn, Victoria 3122, Australia; Jay P. Nair [; ] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Caitlin E. Syme [] School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Philip D. Mannion [] Department of Earth Science and Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK; Paul Upchurch [] Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK; Scott A. Hocknull [] Geosciences, Queensland Museum, 122 Gerler Rd, Hendra, Queensland 4011, Australia; Alex G. Cook [] School of Earth Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia; Travis R. Tischler [] Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia; Timothy Holland [] Kronosaurus Korner, 91 Goldring St, Richmond, Queensland 4822, Australia. *Also affiliated with: Australian Age of Dinosaurs Museum of Natural History, Lot 1 Dinosaur Drive, PO Box 408, Winton, Queensland 4735, Australia.  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