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   12501篇
  免费   294篇
管理学   1511篇
民族学   51篇
人口学   1097篇
丛书文集   78篇
教育普及   2篇
理论方法论   1170篇
综合类   337篇
社会学   6341篇
统计学   2208篇
  2021年   66篇
  2020年   189篇
  2019年   221篇
  2018年   244篇
  2017年   365篇
  2016年   282篇
  2015年   229篇
  2014年   253篇
  2013年   2051篇
  2012年   395篇
  2011年   317篇
  2010年   213篇
  2009年   234篇
  2008年   261篇
  2007年   279篇
  2006年   216篇
  2005年   350篇
  2004年   296篇
  2003年   257篇
  2002年   268篇
  2001年   314篇
  2000年   297篇
  1999年   309篇
  1998年   209篇
  1997年   204篇
  1996年   214篇
  1995年   188篇
  1994年   204篇
  1993年   177篇
  1992年   222篇
  1991年   219篇
  1990年   199篇
  1989年   210篇
  1988年   191篇
  1987年   181篇
  1986年   184篇
  1985年   172篇
  1984年   201篇
  1983年   191篇
  1982年   160篇
  1981年   131篇
  1980年   134篇
  1979年   160篇
  1978年   132篇
  1977年   113篇
  1976年   98篇
  1975年   94篇
  1974年   89篇
  1973年   87篇
  1971年   63篇
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
21.
In this essay we discuss changes in the cultural meaning and significance of time in postmodernism. We begin by examining the experience of time and space in the Middle Ages and its radical alteration following the Renaissance. After a relatively brief period of optimism during the Enlightenment regarding the scientific control over time and space, a new crisis beginning in the mid‐nineteenth century emphasized the increasing disjuncture between external, objective notions of time and the way time was experienced subjectively. We argue that the current literature on time and post‐modernity is best understood in this context, where earlier disequilibriating effects brought about by modern technologies are exacerbated by new developments in transportation and communications technology. Here we discuss the particular effects on topics of interest to social scientists such as changes in notions of personal identity and the effacement of historical time. We conclude with a call for more empirically grounded work on questions concerning time in postmodernism. We lament the paucity of concrete data as well as the excess of useless polemics and recommend several researchers already conducting work in this field.  相似文献   
22.
The authors examined the impact of sense of coherence on the career thought processes of a sample of college students. A. Antonovsky (1987) defined sense of coherence as the global orientation that the world is comprehensible, manageable, and meaningful. Study participants completed the Sense of Coherence Scale (A. Antonovsky, 1987) and the Career Thoughts Inventory (CTI; J. P. Sampson, G. W. Peterson, J. G. Lenz, R. C. Reardon, & D. E. Saunders, 1996). Multivariate tests indicated a medium relationship between sense of coherence and CTI Total and subscale scores; sense of coherence accounted for 14% of the variance. Univariate tests also indicated a medium relationship between sense of coherence and each subscale.  相似文献   
23.
This study examined variations in the relationships among child characteristics, parenting stress, and parental involvement. Participants were 100 two‐parent families with preschool‐aged children. Self‐report and interview data were collected to measure parental involvement, as well as perceptions of child temperament and parental stress. Analyses revealed significant, yet somewhat different, associations between child temperament and parental stress for mothers and fathers. More significant associations were found between perceptions of child temperament and involvement for fathers than for mothers. The associations between child temperament and parental stress and involvement differed on the basis of child and parent gender. Results are discussed in terms of future research on father involvement, as well as programs designed to encourage fathers to assume more active parental roles.  相似文献   
24.
25.
In a longitudinal, community-based study, adolescent protective factors for those at risk for depression were identified that were associated with resilient outcomes in young adulthood. For those with childhood risk factors for major depression, significant protective factors included family cohesion, positive self appraisals, and good interpersonal relations. Findings may help inform the development of prevention and treatment programs for adolescents vulnerable to depression. Implications for future research and clinical practice are discussed.  相似文献   
26.
27.
National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity.  相似文献   
28.
运用参与性诊断(即PRRA)方法对临安示范林地区的森林经营主要政策进行了诊断分析,找出了现行政策存在的问题,如:政策环境欠佳,产权政策不到位,税费政策不合理,林业产品生产、加工和销售脱节,森林生态效益补偿政策欠规范、不合理等.同时,运用参与性设计的方法对若干主要政策进行专项设计,并在此基础上,从优化森林可持续经营的政策环境和规范政策系统运行两方面入手,提出一套科学、合理和有效的适合当地水平的森林可持续经营综合设计方案,以促进示范林网络的发展.  相似文献   
29.
Abstract The effect of nonfarm development on dairy farm survival in New York's highly developed lower Hudson Valley is analyzed. The major hypothesis is that significant losses of dairy farms during this period are the result of urban development pressures. Contrary to this hypothesis, however, the bivariate and multivariate analyses of data from a mail survey of all commercial dairy operators in Dutchess County as of 1984 and industry survivors, exiters, and new entrants through 1990 demonstrate that nonfarm development has a negligible effect on dairy farm survival; rather, survival is significantly affected by age of operator and by family disruption. Thus, demographic and family process factors are found to be more powerful determinants of dairy farm survival in this particular metropolitan context.  相似文献   
30.
对林业税费的经济学分析   总被引:3,自引:0,他引:3  
该文运用经济学的基本工具———供给和需求曲线 ,以商品林为研究对象 ,探讨了林业税费的作用机理和内涵。该文认为商品林生产具有正的外部性 ,市场失灵使生产者将不能提供社会真正所需要的商品林数量。在封闭的市场条件下 ,林业税费会直接成为价格的一部分 ,商品林生产者应当能够获得正常利润 ,与税费高低无关 ,但会使一部分林地退出生产。林业补贴是一种负的林业税收。在开放市场经济条件下 ,国内商品林供应量低于没有林业税收时的商品林供应量 ,更低于考虑社会生态需求时的商品林供应量 ,造成巨大的社会福利损失 ,应减免林业税费、增加林业扶持、取消价格管制。该文进一步研究了与林业税费密切相关的森林采伐限额政策 ,认为对商品林应该完全取消采伐限额政策  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