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   144篇
  免费   12篇
  2023年   1篇
  2020年   2篇
  2019年   9篇
  2018年   5篇
  2017年   8篇
  2016年   15篇
  2015年   4篇
  2014年   6篇
  2013年   54篇
  2012年   4篇
  2011年   2篇
  2010年   5篇
  2009年   7篇
  2008年   4篇
  2007年   2篇
  2005年   1篇
  2004年   1篇
  2003年   3篇
  2002年   1篇
  2000年   1篇
  1997年   1篇
  1996年   2篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1987年   1篇
  1986年   1篇
  1985年   3篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
  1980年   3篇
  1978年   1篇
  1974年   1篇
  1969年   1篇
排序方式: 共有156条查询结果,搜索用时 15 毫秒
1.
2.
3.
Cities across America look for management strategies useful for accomplishing their responsibilities and programs. While some cities include privatization strategies in their management portfolios, others do not, and the underlying reasons are not readily apparent. This study seeks to gain some insight into this disparity through several questions: Why do some cities use more privatization than others? Are privatization levels higher in fiscally healthy or fiscally stressed cities? Where are the cities that use privatization located? This study attributes municipal privatization levels in medium-sized cities, in part, to degree of wealth, fiscal stress, and location. The findings suggest that privatization levels are higher in wealthy, fiscally healthy, suburban cities.  相似文献   
4.
5.
Rozefelds, A.C., Dettmann, M.E., Clifford, H.T. & Lewis, D., August 2015. Macrofossil evidence of early sporophyte stages of a new genus of water fern Tecaropteris (Ceratopteridoideae: Pteridaceae) from the Paleogene Redbank Plains Formation, southeast Queensland, Australia. Alcheringa 39,. ISSN 0311-5518.

Water fern foliage is described from the Paleogene Redbank Plains Formation at Dinmore in southeast Queensland. The material, which is based upon leaf impressions, records early sporophyte growth stages. The specimens occur at discrete levels in clay pits at Dinmore, and the different leaf stages present suggest that they represent colonies of young submerged plants, mats of floating leaves, or a mixed assemblage of both. The leaf material closely matches the range of variation evident in young sporophytes of Ceratopteris Brongn., but in the complete absence of Cenozoic fossils of the spore genus Magnastriatites Germeraad, Hopping & Muller emend. Dettmann & Clifford from mainland Australia, which are the fossil spores of this genus, it is referred to a new genus, Tecaropteris. The record of ceratopterid-like ferns adds significantly to our limited knowledge of Cenozoic freshwater plants from Australia. The geoheritage significance of sites, such as Dinmore, is discussed briefly.

Andrew C. Rozefelds [], Queensland Museum GPO Box 3300, South Brisbane, 4101, Queensland, Australia and School of Earth Sciences, University of Queensland, St Lucia, 4072, Queensland, Australia; Mary Dettmann [], H. Trevor Clifford [] and Debra Lewis [], Queensland Museum, GPO Box 3300, South Brisbane, 4101, Queensland, Australia.  相似文献   

6.
7.
8.
9.
10.
Since his first book The Cholera Years appeared in 1962, Charles Rosenberg has had an enormous influence on the history of medicine. Not the least of that influence has been exercised through his role as a graduate teacher, advisor, and mentor. This article compares Rosenberg's work with that of his students, to see if there is such a historiographic identity as the "Rosenberg School." The authors, two Rosenberg students from different generations, conclude that there is not such a school, at least in the classic sense of the term. Yet they argue that certain common assumptions, or "Rosenberg Rules," have been passed on from Rosenberg to the other scholars he has influenced. They also discuss the challenges they have encountered in applying Charles's conceptual framework, worked out primarily in pre-1920 terms, to the late twentieth-century history of American medicine.  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