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   6802篇
  免费   337篇
  2020年   84篇
  2019年   119篇
  2018年   197篇
  2017年   198篇
  2016年   267篇
  2015年   175篇
  2014年   167篇
  2013年   1719篇
  2012年   180篇
  2011年   242篇
  2010年   195篇
  2009年   205篇
  2008年   164篇
  2007年   176篇
  2006年   170篇
  2005年   88篇
  2004年   94篇
  2003年   95篇
  2002年   82篇
  2001年   116篇
  2000年   108篇
  1999年   100篇
  1998年   86篇
  1997年   87篇
  1996年   66篇
  1995年   72篇
  1994年   52篇
  1993年   84篇
  1992年   62篇
  1991年   62篇
  1990年   63篇
  1989年   71篇
  1988年   50篇
  1987年   69篇
  1986年   57篇
  1985年   76篇
  1984年   71篇
  1983年   86篇
  1982年   71篇
  1981年   63篇
  1980年   73篇
  1979年   64篇
  1978年   71篇
  1977年   76篇
  1976年   77篇
  1975年   61篇
  1974年   56篇
  1973年   50篇
  1972年   48篇
  1971年   35篇
排序方式: 共有7139条查询结果,搜索用时 15 毫秒
81.
The advent of new techniques of dental ageing has permitted inferences about the age-structures of ancient animal populations on the basis of faunal remains. Unfortunately, inference from archaeological populations of faunal elements to the age-structure of ancient herds is fraught with both sampling problems and logical difficulties. The relationship between a living herd—a dynamic system characterized by growth—and a static archaeological population is more complex than that assumed by current models based on kill-off patterns and survivorship curves. Using a computer simulation, these logical relationships are explored, and the effects of herd growth on the composition of live and death populations are evaluated. By employing the simulation within a deductive framework, constrained by ethnographically derived criteria for reproduction, mortality, and economic viability in the Near East, it is possible to determine whether certain archaeological kill-off patterns could represent viable herding systems. Examples were found to vary widely in terms of both demographic plausibility and economic viability. Some implications for the possible course of ova-caprine domestication in the Near East are discussed.  相似文献   
82.
83.
84.
The beginning of the Late Bronze Age in the Aegean has usually been thought to coincide with the start of the Eighteenth Dynasty in Egypt, and radiocarbon dates (which consistently suggest an earlier chronology) have been rejected by Aegean specialists because they do not agree with this view. Evidence from pottery is used to re-examine the links between the Aegean and Egypt, with the conclusion that the Aegean Late Bronze Age began during the Hyksos period.  相似文献   
85.
86.
In September 1968, one of the authors (P. Mayes), having been appointed Head of Mission by the British Ministry of Overseas Development to act as advisor to the Jamaica National Trust Commission, made recommendations which formed the basis for the establishment of the Port Royal Project. The Project is concerned with the excavation, conservation and presentation of 17th century Port Royal, which was founded in 1655 and destroyed by an earthquake in 1692 (see Fig. 1). For the purposes of archaeology the area was divided into three: the Archaeological-Historical Reserve, encompassing the protected underwater area and lands currently occupied by government facilities at the west end of Port Royal; the area in the centre of Port Royal which is protected archaeologically by modern housing and the area at the east end of Port Royal in which it was proposed that commercial expansion should be allowed on land held on lease from the Jamaican government. Work began early in 1969 in a section of this last area, which was threatened, at that time, by the construction of an hotel. This area was part of the shoal water section of sunken Port Royal (see below and Fig. 2). Since that date excavation headquarters and conservation laboratories have been established in the old naval hospital and the construction of a major museum, the first phase of the presentation programme, has begun.  相似文献   
87.
This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed.  相似文献   
88.
89.
90.
A method is described for the identification of the origin of flint artefacts. The method is based on the variation in the trace element concentrations for different origins. The trace element concentrations were determined by non-destructive neutron activation analysis. The identification was obtained from a pattern recognition analysis.  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