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   2895篇
  免费   109篇
管理学   620篇
民族学   28篇
人口学   250篇
丛书文集   7篇
理论方法论   261篇
综合类   20篇
社会学   1307篇
统计学   511篇
  2023年   31篇
  2022年   24篇
  2021年   22篇
  2020年   41篇
  2019年   97篇
  2018年   139篇
  2017年   146篇
  2016年   127篇
  2015年   92篇
  2014年   109篇
  2013年   529篇
  2012年   117篇
  2011年   95篇
  2010年   105篇
  2009年   100篇
  2008年   86篇
  2007年   96篇
  2006年   103篇
  2005年   75篇
  2004年   66篇
  2003年   53篇
  2002年   85篇
  2001年   69篇
  2000年   56篇
  1999年   39篇
  1998年   23篇
  1997年   27篇
  1996年   25篇
  1995年   15篇
  1994年   13篇
  1993年   25篇
  1992年   24篇
  1991年   24篇
  1990年   14篇
  1989年   19篇
  1988年   21篇
  1987年   19篇
  1986年   13篇
  1985年   21篇
  1984年   19篇
  1983年   17篇
  1982年   17篇
  1981年   19篇
  1980年   13篇
  1979年   12篇
  1978年   13篇
  1976年   15篇
  1975年   14篇
  1972年   12篇
  1971年   11篇
排序方式: 共有3004条查询结果,搜索用时 433 毫秒
51.
Early in development, children explore and combine objects in increasingly complex ways. One manual skill, object construction, represents a major shift in how objects are explored relative to other objects. Despite recent connections with cognitive functioning such as spatial skills, the development of object construction ability has rarely been studied and its trajectory has not been adequately described. The purpose of this study was to describe the development of three types of object construction (stacking, nesting, and affixing) across 5 monthly infant visits and 7 monthly toddler visits using a longitudinal design and a large sample size. Infants (10–14 months, = 131) and toddlers drawn from the infant sample (18–24 months, = 65) were given sets of age‐appropriate toys each of which elicited at least one type of constructive play. We described success at different construction tasks and identified trends for construction skill for infant and toddler development using multilevel modeling. We found that each of the three construction actions developed in unique ways across the 10‐ to 24‐month period. Infant construction skill predicted the development of toddler skill, but toddler construction skill diverged from infant trajectories. We discuss the role of combination strategies in the development of object construction skill and how object construction could be related to other domains of development.  相似文献   
52.
This study addressed the role of actual and perceived similarity in peer rejection of socially anxious adolescents. Videotapes of 20 high and 20 low socially anxious adolescents (13–17 years old) giving a speech were rated by groups of unfamiliar peers with regard to perceived similarity and desire for future interaction (lower scores indicating rejection). Actual similarity between speakers and observers regarding social anxiety and gender was also taken into account. Findings showed that high socially anxious students were more rejected and that perceived but not actual similarity between peer observers and speakers (partly) mediated rejection.  相似文献   
53.
Bonuses in the finance sector may be based on too short time intervals for environmental and social factors to be taken into account in investment decisions. We report two experiments to investigate whether investors prefer short-term to long-term bonuses. In Experiment 1 employing 27 undergraduates, preferences were measured for four short-term certain bonuses, evenly distributed across a time interval, and one certain long-term bonus at the end of the time interval. A majority chose the short-term bonuses, and in order for the long-term bonus to be equally preferred it had to be about 40% higher than the four added short-term bonuses. Experiment 2 employing another 36 undergraduates introduced outcome uncertainty that more accurately reflects the choices stock investors face. The participants again choose between a long-term bonus and four distributed short-term bonuses. It was shown that uncertainty made more participants prefer the long-term bonus to the added short-term bonuses than when the outcome was certain. A smaller increase of the long-term bonus of about 20% was now required to make it equally attractive as the four added short-term bonuses.  相似文献   
54.
55.
The world is ageing both at an individual and a population level, and population ageing is truly a global phenomenon. Life expectancies at birth have increased at the global level from 47 years in the mid-20th century to around 70 years today, and are expected to rise to 76 years by the mid-21st century. The proportion of the world’s population aged 60 years and over has increased from 8 % in the mid-20th century to 12 %, and by 2050 it is expected to reach 21 %. The emergence of large numbers of centenarians has accompanied this development. This paper outlines this emergence historically and the likely growth in the number of centenarians in the 21st century, in particular in England and Wales, analysing mortality trends since 1840 and the rise in the number of centenarians in the 20th and 21st centuries. The number of centenarians in England and Wales increased from around 160 in 1922 to almost 12,500 by 2012, but if mortality at all ages had remained constant from 1912 to 2012, then by 2012 the number of centenarians would only have been around 720. By 2100, the number of centenarians is expected to reach around 1.4 million, but if future mortality at all ages were to remain constant, then by 2100 the number of centenarians would be around 78,000. However, if predicted mortality for those aged 55 years and over was to decrease by an additional 5 % every 5 years until 2100, then the number of centenarians in England and Wales would reach around 1.8 million by the end of the century.  相似文献   
56.
Objective: To examine the perceptions among faculty and health professional students regarding mandatory vaccination policies on a health sciences campus. Participants: A total of 296 faculty and 244 students completed surveys during Fall 2015. Methods: The online survey administered to individuals who received the influenza vaccine during the fall 2015 influenza vaccination clinic season included five items evaluating perceptions of employer mandatory vaccination requirements. Results: Chi-square analysis indicated that although faculty and students agree mandatory vaccinations in a health care environment are appropriate, faculty are more likely than students to get vaccinated in the absence of a mandate. Additionally, a small fraction of faculty would consider employment elsewhere when facing this mandate. Conclusions: Overall, faculty and students had favorable perceptions about mandatory influenza vaccine policies. Since students were less likely to be vaccinated in the absence of a mandate, education of students should be improved to support the importance of vaccinations in a health care environment.  相似文献   
57.
58.
With the fall of the Berlin Wall in 1989, open migration from East to West Germany became possible. Between 1989 and 2007, roughly 10 per cent of the East’s population at the time of reunification migrated from east to west. The emigrants were predominantly young and female. This selective migration pattern led to a tremendous deficit of females in the 18–29 year old age group in eastern Germany. Overall, the sex ratio in that age group is as low as 89 females per 100 males in the east. In some rural counties, the sex ratio is 80 females per 100 males. We find that excess female emigration at the county level is associated with gender disparities in educational attainment that favour women, a labour market structure that favours men and the lower availability of potential partners with similar levels of education in eastern Germany.  相似文献   
59.
This study examined the role of depressive symptoms, acute intoxication, and risk rationale in men’s use of condom use resistance (CUR) tactics in an experimental study. Participants included 313 heterosexual male, nonproblem drinkers, ages 21 to 30. Participants were randomized to one of four beverage conditions: no alcohol, placebo, low (.04%) alcohol dose, or high (.08%) alcohol dose. They read an eroticized scenario depicting a consensual sexual encounter with a female partner who requested a condom to prevent either pregnancy or sexually transmitted infections (STIs) (risk rationale) and then indicated their intentions to use 10 different CUR tactics. Hypotheses related to the pharmacological, dosage, and expectancy effects of alcohol were tested in a generalized linear model. In intoxicated (.04% and .08%) men who were given a pregnancy risk rationale, depressive symptoms were associated with stronger intentions to use CUR tactics than in sober (control and placebo) men. Men who received a high alcohol dose (.08%) and who were given a pregnancy risk rationale reported higher intentions to use CUR tactics than those who received a lower alcohol dose (.04%). Findings suggest that the pharmacological effects of alcohol on men’s likelihood to resist condoms vary by the saliency of the risk rationale and mood-related variables.  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