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   41259篇
  免费   1637篇
  2020年   536篇
  2019年   827篇
  2018年   923篇
  2017年   1143篇
  2016年   1222篇
  2015年   939篇
  2014年   921篇
  2013年   14154篇
  2012年   1058篇
  2011年   1081篇
  2010年   1078篇
  2009年   1072篇
  2008年   1011篇
  2007年   910篇
  2006年   822篇
  2005年   571篇
  2004年   567篇
  2003年   520篇
  2002年   501篇
  2001年   483篇
  2000年   415篇
  1999年   483篇
  1998年   453篇
  1997年   416篇
  1996年   394篇
  1995年   406篇
  1994年   351篇
  1993年   404篇
  1992年   381篇
  1991年   284篇
  1990年   283篇
  1989年   289篇
  1988年   296篇
  1987年   308篇
  1986年   281篇
  1985年   398篇
  1984年   437篇
  1983年   431篇
  1982年   380篇
  1981年   374篇
  1980年   412篇
  1979年   406篇
  1978年   397篇
  1977年   419篇
  1976年   371篇
  1975年   376篇
  1974年   282篇
  1973年   258篇
  1972年   240篇
  1970年   217篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
133.
134.
135.
136.
137.
An investigation of three Andean towns in their regional setting forms the basis for an assessment of urban-rural demographic differences. The towns are found to have been ethnically distinct, with a larger proportion of whites than the mainly Indian rural areas. The urban populations also had a larger surplus of women, lower average marriage ages for women but lower proportions married, a higher illegitimacy rate and a slightly older age structure. Trends in urban districts differed from those in rural areas. The towns suffered major population losses, and their share of the regional population fell from nearly 10% in 1778 to around 5% in 1841. The factors affecting population trends are examined in order to identify those which had a differential urban-rural impact. Earthquake and warfare were of key significance. In a regional context of economic depression and population stagnation, these two catastrophes instigated a major urban recession. The three towns shared in the urban decline experienced in many parts of Latin America, but their recession was particularly pronounced owing to the impact of catastrophes.  相似文献   
138.
ABSTRACT Casinos are often considered as a “growth pole” strategy to revitalize dilapidated regions. However, voters often reject casinos due to their perceived adverse impact on crime. Using a quasi-experimental design we analyze the impact of the casinos on crime spillover from Atlantic City to other localities in the region. We found that the level of crime in localities adjacent to Atlantic City and along the major nontoll routes to Philadelphia and New York City up to approximately 30 miles from Atlantic City rose significantly following the introduction of casinos. Crime levels are higher than they would have been in the absence of casinos.  相似文献   
139.
ABSTRACT. In a simple urban model, where the only spatial distinction made is between center and suburb, we introduce a uniform distribution of preferences for land. Under a logarithmic utility function, we examine how the location and consumption decisions of individuals differ in consequence of their different preferences for land. Comparative statics indicate that the qualitative response of the city at equilibrium to changes in per capita income and transportation cost is not affected by the introduction of such heterogeneity. Possible extensions are also briefly discussed.  相似文献   
140.
ABSTRACT. This paper uses a large data base to study metropolitan labor demand functions. The data are disaggregated by two-digit SICs in manufacturing for SMS As, and are corrected for changing SMSA boundaries. Labor demand elasticities are estimated for factor and commodity prices, transportation costs, state and local taxes and expenditures, and production-function shifters. Estimates from different years allow one to test Le Chatelier's principle in the context of interregional change.  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