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   16978篇
  免费   513篇
  国内免费   14篇
管理学   2083篇
民族学   101篇
人才学   2篇
人口学   1553篇
丛书文集   176篇
教育普及   1篇
理论方法论   1695篇
综合类   736篇
社会学   9022篇
统计学   2136篇
  2023年   80篇
  2021年   132篇
  2020年   260篇
  2019年   323篇
  2018年   396篇
  2017年   589篇
  2016年   412篇
  2015年   328篇
  2014年   383篇
  2013年   2732篇
  2012年   601篇
  2011年   608篇
  2010年   490篇
  2009年   448篇
  2008年   530篇
  2007年   539篇
  2006年   565篇
  2005年   488篇
  2004年   403篇
  2003年   363篇
  2002年   386篇
  2001年   422篇
  2000年   367篇
  1999年   345篇
  1998年   259篇
  1997年   230篇
  1996年   241篇
  1995年   232篇
  1994年   214篇
  1993年   212篇
  1992年   243篇
  1991年   236篇
  1990年   223篇
  1989年   216篇
  1988年   209篇
  1987年   226篇
  1986年   202篇
  1985年   210篇
  1984年   223篇
  1983年   190篇
  1982年   169篇
  1981年   150篇
  1980年   143篇
  1979年   159篇
  1978年   124篇
  1977年   100篇
  1976年   118篇
  1975年   126篇
  1974年   92篇
  1971年   72篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Editorial     
Ohne Zusammenfassung
Editorial
  相似文献   
32.
33.
34.
35.
Sleep is essential for our health and well‐being but it has, historically, been the subject of little sociological study. Yet sleep is not, as common sense would have us believe, ‘asocial inaction’. Like our waking lives, it is a time of interaction. The sociology of sleep presently exists in a state similar to the early stages of development of the sociology of the body, waiting for something like Frank's (1991 ) typology of body action, which served as a heuristic guide through which action and its multifaceted components could be understood. This paper argues that one productive analytical framework is to adapt Watson's (2000 ) ‘male body schema’ for the sociological investigation of sleep. This revolves around four interrelated forms of embodiment: normative (opinions and perceptions about healthy sleep behaviour); pragmatic (‘normal’ as related to social role); experiential (feelings related to sleep); and visceral (the biological body and sleep). The possibilities this model provides for the sociology of sleep is illustrated in the paper through the analysis of a case study of sleep negotiation between a couple.  相似文献   
36.
37.
38.
Children may be more susceptible to toxicity from some environmental chemicals than adults. This susceptibility may occur during narrow age periods (windows), which can last from days to years depending on the toxicant. Breathing rates specific to narrow age periods are useful to assess inhalation dose during suspected windows of susceptibility. Because existing breathing rates used in risk assessment are typically for broad age ranges or are based on data not representative of the population, we derived daily breathing rates for narrow age ranges of children designed to be more representative of the current U.S. children's population. These rates were derived using the metabolic conversion method of Layton (1993) and energy intake data adjusted to represent the U.S. population from a relatively recent dietary survey (CSFII 1994–1996, 1998). We calculated conversion factors more specific to children than those previously used. Both nonnormalized (L/day) and normalized (L/kg-day) breathing rates were derived and found comparable to rates derived using energy estimates that are accurate for the individuals sampled but not representative of the population. Estimates of breathing rate variability within a population can be used with stochastic techniques to characterize the range of risk in the population from inhalation exposures. For each age and age-gender group, we present the mean, standard error of the mean, percentiles (50th, 90th, and 95th), geometric mean, standard deviation, 95th percentile, and best-fit parametric models of the breathing rate distributions. The standard errors characterize uncertainty in the parameter estimate, while the percentiles describe the combined interindividual and intra-individual variability of the sampled population. These breathing rates can be used for risk assessment of subchronic and chronic inhalation exposures of narrow age groups of children.  相似文献   
39.
40.
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