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   780篇
  免费   62篇
  2023年   13篇
  2022年   2篇
  2021年   5篇
  2020年   21篇
  2019年   41篇
  2018年   44篇
  2017年   63篇
  2016年   55篇
  2015年   32篇
  2014年   27篇
  2013年   179篇
  2012年   30篇
  2011年   46篇
  2010年   36篇
  2009年   32篇
  2008年   24篇
  2007年   15篇
  2006年   22篇
  2005年   11篇
  2004年   19篇
  2003年   9篇
  2002年   17篇
  2001年   7篇
  2000年   6篇
  1999年   11篇
  1998年   5篇
  1997年   7篇
  1996年   3篇
  1995年   4篇
  1994年   4篇
  1993年   5篇
  1992年   5篇
  1991年   1篇
  1990年   4篇
  1989年   3篇
  1988年   3篇
  1987年   1篇
  1986年   1篇
  1985年   4篇
  1984年   6篇
  1983年   2篇
  1982年   2篇
  1981年   1篇
  1980年   3篇
  1979年   5篇
  1975年   1篇
  1974年   1篇
  1972年   3篇
  1971年   1篇
排序方式: 共有842条查询结果,搜索用时 24 毫秒
101.
Umhlatuzana Rock Shelter is a long-sequence Middle and Later Stone Age site in KwaZulu-Natal, South Africa. Jonathan Kaplan excavated the site and analysed the material in the 1980s as a rescue project. For many years thereafter the collection remained untouched, partly because of doubts raised about the stratigraphic integrity of the site. Using single-grain OSL dating we show that post-depositional mixing of sediment was restricted to time-specific, small-scale events. The OSL ages obtained for the Howiesons Poort and pre-Howiesons Poort are comparable to those of other southern African sites with unambiguous Howiesons Poort and Still Bay Industries. Based on morphological and other characteristics, we reason that the Still Bay is represented at Umhlatuzana, and announce the presence of a serrated point assemblage closely associated in time with the Still Bay points.  相似文献   
102.
103.
This study collects data from three major journals and analyses them in order to assess the recent (1997–2006) nature of the study of palaeopathology within Britain. It considers the types of study published (case, population or method), whether findings are integrated with other data, the particular ‘theme’ that is considered (diet, activity patterns, etc) and the particular pathological condition focused upon (metabolic, dental, etc). The findings show there is a move away from the traditional case study and an increase in the acknowledgement of the value of integrating data with wider information. There is also a bias towards certain ‘themes’ and pathologies, reasons for which are discussed. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
104.
105.
This essay examines the late Ming-dynasty Chan master Yunqi Zhuhong’s commentary on the Brahma Net Sutra (Fanwangjing), which it takes up in order to explore his discourse concerning both Chan realism and his ensuing rejection of mainstream Chan gongan rhetoric. The Brahma Net Sutra contains a list of major and minor precepts governing proper morality for monastic and lay Buddhists. Zhuhong’s interpretation of the Twenty-First Minor Precept, which prohibits revenge, offers insight into his sense of political realism regarding the relationship between gradual teachings, provisional truths, and ultimate truth. His interpretation of the Tenth Minor Precept, which prohibits storing weapons, demonstrates his moral realism in contrast to Chan’s traditional use of pedagogical violence. Zhuhong’s realist discourse, influenced by the teachings of the Buddhist Vinaya as well as by engagement with Confucian ethics, presents an overlooked counter-narrative shift that contrasts with the emphasis on sudden enlightenment and antinomianism in Chan gongan discourse typical of the Tang and Song dynasties.  相似文献   
106.
Matthew T. Huber 《对极》2009,41(3):465-486
Abstract:  While the critical literature has focused on the geography of oil production, the politics of "outrageous" gasoline prices in the United States provide a fertile path toward understanding the wider geography of petro-capitalism. Despite the deepening contradictions of US oil consumption, "pain at the pump" discourse projects a political sense of entitlement to low priced gasoline. I use a value-theoretical perspective to examine this politics as not only about the quantitative spectrum of price, but also the historical sedimentation of qualitative use-values inscribed in the commodity gasoline. Gasoline is analyzed both as a use-value among many within the postwar value of labor power and as a singular use-value fueling broader imaginaries of a national "American way of life." While use-value still represents an open site of cultural and political struggle infused within value itself, the case of gasoline illustrates how use-values are not automatically mobilized toward politically savory ends.  相似文献   
107.
108.
We report the recovery of short fragments of PCR amplifiable ancient DNA from exoskeletal fragments of the grain weevil Sitophilus granarius (L.) extracted from Roman and medieval deposits in Northern England. If DNA preservation in archaeological insect remains is widespread then many applications in the spheres of evolutionary studies and archaeology can be conceived, some of which are outlined.  相似文献   
109.
The detection and identification of protein residues from archaeological artefacts has been the subject of considerable controversy over the past two decades, this controversy spurring the application of a range of different analytical methods. Part of the debate surrounds the ability of the methods to uniquely identify original proteins. Another is the apparent contradiction between the ease of extraction in the laboratory of residues that have managed to survive in sediment over millennia; some studies use simple solvents including water, whilst others claim that efficient extraction requires the destruction of the artefact.Desorption electrospray ionisation mass spectrometry (DESI-MS) offers the potential to directly analyse proteins bound to the surface of artefacts. The method permits desorption of analytes under ambient conditions directly from a wide range of surfaces with little or no sample preparation. This has already led to its application in a range of areas, including forensic analysis of trace levels of narcotic drugs. It does not require destruction of the artefact (e.g. by drilling or dissolution) and can work in concert with other methods (for instance it could be used as a screening tool prior to lipid extraction).Here we report the construction of a DESI-MS interface and consider the potential of the method to contribute to the debate surrounding the preservation of proteins on artefacts. The DESI-MS interface was fitted to a conventional ion trap mass spectrometer and tested using peptides and proteins artificially applied to the surface of flint flakes and potsherd samples. A range of intact proteins was analysed; the DESI interface identified test proteins up to a maximum molecular weight of approximately 20 kDa. Peptides generated from these and larger proteins could be detected using DESI-MS following tryptic digestion in situ. The collected data allowed identification of the originating proteins. The potential applications to archaeological science of this new analytical tool are discussed.  相似文献   
110.
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