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   7312篇
  免费   317篇
  7629篇
  2023年   36篇
  2020年   108篇
  2019年   161篇
  2018年   197篇
  2017年   243篇
  2016年   268篇
  2015年   178篇
  2014年   174篇
  2013年   2165篇
  2012年   211篇
  2011年   240篇
  2010年   250篇
  2009年   206篇
  2008年   168篇
  2007年   160篇
  2006年   155篇
  2005年   171篇
  2004年   124篇
  2003年   117篇
  2002年   111篇
  2001年   111篇
  2000年   107篇
  1999年   108篇
  1998年   80篇
  1997年   80篇
  1996年   51篇
  1995年   70篇
  1994年   57篇
  1993年   69篇
  1992年   58篇
  1991年   64篇
  1990年   59篇
  1989年   49篇
  1988年   49篇
  1987年   59篇
  1986年   56篇
  1985年   76篇
  1984年   83篇
  1983年   86篇
  1982年   65篇
  1981年   72篇
  1980年   62篇
  1979年   67篇
  1978年   60篇
  1977年   54篇
  1976年   47篇
  1975年   44篇
  1974年   47篇
  1973年   41篇
  1972年   35篇
排序方式: 共有7629条查询结果,搜索用时 15 毫秒
71.
72.
An important line of research concerning historical fertility patterns in currently developed countries of Europe has concluded that, prior to the fertility transition, marital fertility was essentially constant over time, and deliberate fertility control was virtually unknown. It has been argued that variations over time in overall fertility were largely the consequence of variations in nuptiality. Other researchers have challenged these views and present evidence for the existence of a significant minority of fertility controllers in pretransition populations. In this article, we find support for this second view and argue that (1) there was significant, non-random variation in marital fertility over time, prior to the transition; (2) in many cases, this variation in marital fertility was large relative to contemporaneous variations in nuptiality; and (3) in a substantial minority of the cases, the variation over time in pretransition marital fertility was so large that it is suggestive of deliberate fertility control. Thus, our findings question the view of fertility transition as an innovation in deliberate marital fertility control. While most of our evidence is based on data from England and Wales, we find corroboration of our key results in other European data.  相似文献   
73.
Blue glass trade beads from well-dated late seventeenth- to early twentieth-century sites and collections have been analysed non-destructively by instrumental neutron activation analysis. The beads display enough variations in their elemental contents to allow us to characterize the different chemistries. The implication of these results is that similar chemical analyses of blue beads from undated archaeological sites may be used to help date the sites, since each bead chemistry has a specific earliest period.  相似文献   
74.
David Schmid 《对极》1995,27(3):242-269
Radical geographers often discuss how contemporary urban space is becoming increasingly violent and dangerous. They pay much less attention to the question of how to make this space safe. In contrast, detective fiction focuses precisely on how to take danger out of the city. It therefore provides radical geographers with imaginative models of how different levels of space are linked through forms of violence. Detective fiction challenges accounts of the urban spatialization of power that over-simplify relations between city inhabitants as a clash between “oppressor” and “oppressed.” By suggesting how a subject can simultaneously oppress through and be oppressed by volence, detective fiction shows the contradictory multiplicity of people's spatial identifications.  相似文献   
75.
Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP.  相似文献   
76.
77.
The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field.  相似文献   
78.
79.
Random Time Sampling is an innovative data collection method which has potential for adaptation and use by geographers. Individual pocket-sized programmable beepers were used in a pilot study of the uses of time by older households and older people's attitudes to different activities. Random beeps were used to prompt individuals living in eleven Melbourne suburbs to record time use data in diaries over a period of a week. The method proved extremely effective and reliable, and many participants reporting that they enjoyed the exercise.  相似文献   
80.
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