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   2555篇
  免费   107篇
  2662篇
  2020年   39篇
  2019年   46篇
  2018年   58篇
  2017年   58篇
  2016年   77篇
  2015年   49篇
  2014年   53篇
  2013年   754篇
  2012年   83篇
  2011年   101篇
  2010年   100篇
  2009年   78篇
  2008年   59篇
  2007年   57篇
  2006年   66篇
  2005年   48篇
  2004年   27篇
  2003年   38篇
  2002年   25篇
  2001年   40篇
  2000年   39篇
  1999年   57篇
  1998年   29篇
  1997年   27篇
  1996年   18篇
  1995年   28篇
  1994年   21篇
  1993年   23篇
  1992年   19篇
  1991年   21篇
  1990年   25篇
  1989年   24篇
  1988年   17篇
  1987年   27篇
  1986年   25篇
  1985年   32篇
  1984年   29篇
  1983年   29篇
  1982年   25篇
  1981年   23篇
  1980年   26篇
  1979年   23篇
  1978年   23篇
  1977年   18篇
  1975年   15篇
  1974年   12篇
  1973年   20篇
  1972年   17篇
  1970年   13篇
  1966年   11篇
排序方式: 共有2662条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.
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   
55.
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   
56.
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   
57.
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   
58.
59.
Reviews     
“JINNAH: CREATOR OF PAKISTAN.” by Hector Bolitho. John Murray. London, 7954. Pp. x and 244, illus.

“WANTED: AN ASIAN POLICY,” by Edwin O. Reisehauer. New York: Knopf, 7955. Pp. 256.  相似文献   

60.
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