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   8291篇
  免费   127篇
  国内免费   1篇
管理学   1112篇
民族学   29篇
人口学   720篇
丛书文集   31篇
理论方法论   705篇
综合类   140篇
社会学   3752篇
统计学   1930篇
  2020年   118篇
  2019年   173篇
  2018年   175篇
  2017年   262篇
  2016年   178篇
  2015年   155篇
  2014年   183篇
  2013年   1530篇
  2012年   247篇
  2011年   205篇
  2010年   187篇
  2009年   162篇
  2008年   226篇
  2007年   225篇
  2006年   189篇
  2005年   163篇
  2004年   144篇
  2003年   130篇
  2002年   145篇
  2001年   186篇
  2000年   166篇
  1999年   149篇
  1998年   128篇
  1997年   130篇
  1996年   128篇
  1995年   114篇
  1994年   86篇
  1993年   126篇
  1992年   143篇
  1991年   120篇
  1990年   130篇
  1989年   109篇
  1988年   110篇
  1987年   113篇
  1986年   100篇
  1985年   86篇
  1984年   117篇
  1983年   98篇
  1982年   95篇
  1981年   64篇
  1980年   93篇
  1979年   106篇
  1978年   73篇
  1977年   83篇
  1976年   72篇
  1975年   85篇
  1974年   68篇
  1973年   55篇
  1972年   61篇
  1971年   52篇
排序方式: 共有8419条查询结果,搜索用时 15 毫秒
21.
The most popular methodology used by the US International Trade Commission (USITC) commissioners to determine whether dumped and/or subsidized imports injure competing domestic industries has been rejected by reviewing bodies because it does not distinguish injury caused by unfairly traded imports from other demand or supply changes. We estimate injury to the domestic industry due to changes in unfairly traded import price and to other causes for 44 USITC dumping and/or subsidy investigations. Change in unfairly traded import price was typically not the most important cause of injury to the domestic industry. (JEL F13 )  相似文献   
22.
23.
We examine how attention to animacy information may contribute to children's developing knowledge of language. This research extends beyond prior research in that children were shown dynamic events with novel entities, and were asked not only to comprehend sentences but to use sentence structure to infer the meaning of a new word. In a 4 × 3 design, animacy status (e.g., animate agent, inanimate patient) and labeling syntax (agent, patient, nonlabel control) were varied. Across most events, 2 1/2‐year‐old participants responded as if they expected animate entities to be named. However, in a prototypical (animate agent‐inanimate patient) event condition, children responded differentially across different syntactic structures. Thus, the clearest evidence for attention to syntactic cues was found in the prototypical event condition. These results suggest that young children attend to the animacy status of unfamiliar entities, that they have expectations about animacy relations in events, and that these expectations support emerging syntactic knowledge.  相似文献   
24.
A mechanistic model is presented describing the clearance of a compound in a precision-cut liver slice that is incubated in a culture medium. The problem of estimating metabolic rate constants in PBPK models from liver slice experiments is discussed using identifiability analysis. From the identifiability problem analysis, it appears that in addition to the clearance, the compound's free fraction in the slice and the diffusion rate of the exchange of the compound between culture medium and liver slice should be identified. In addition, knowledge of the culture medium volume, the slice volume, the compound's free fraction, and octanol-water-based partition between medium and slice is presupposed. The formal solution for identification is discussed from the perspective of experimental practice. A formally necessary condition for identification is the sampling of parent compound in liver slice or culture medium. However, due to experimental limitations and errors, sampling the parent compound in the slice together with additional sampling of metabolite pooled from the medium and the slice is required for identification in practice. Moreover, it appears that identification results are unreliable when the value of the intrinsic clearance exceeds the value of the diffusion coefficient, a condition to be verified a posteriori.  相似文献   
25.
Existential, or existential-phenomenological philosophical approaches to the social psychology of risk perception provide a novel framework for understanding issues that are common to all humanity, such as fear of death, freedom and responsibility, isolation and meaninglessness, as these anxieties are a function of existing, or being-in-the-world. These fundamental anxieties can be related theoretically to the ways people perceive risks within social and cultural milieus, and can also be used practically within case studies, as demonstrated in the three examples presented, which examine perceptions of climate change, food-related risks, and environmental awareness via a mixture of quantitative and qualitative techniques. The discussion focuses on the possible insights that can be gained from taking an existential perspective on risk perception, and relates notions of contemporary technologically-oriented societies to the existential challenges faced by individuals and societies in the contemporary world.  相似文献   
26.
Recent studies have shown that group differences in marital stability and satisfaction can be predicted based on premarital relationship quality. There is also a growing literature indicating that there are distinct types of relationships, both premaritally and developmentally over time. This study examined the relationship between the four premarital types (Vitalized, Harmonious, Traditional, and Conflicted) identified by Fowers and Olson (1992) and relationship outcome over a 3-year period with 393 couples. A substantial relationship was found, with conflicted couples being the most likely to separate or divorce. Vitalized couples had the highest levels of satisfaction, followed by Harmonious, Traditional, and Conflicted couples. Traditional couples were less likely to have divorced than Harmonious couples, even though Harmonious couples had higher premarital relationship satisfaction scores.  相似文献   
27.
This paper presents the results of a study that identified how often a probabilistic risk assessment (PRA)should be updated to accommodate the changes that take place at nuclear power plants. Based on a 7-year analysis of design and procedural changes at one plant, we consider 5 years to be the maximum interval for updating PRAs. This conclusion is preliminary because it is based on the review of changes that occurred at a single plant, and it addresses only PRAs that involve a Level 1 analysis (i.e., a PRA including calculation of core damage frequency only). Nevertheless, this conclusion indicates that maintaining a useful PRA requires periodic updating efforts. However, the need for this periodic update stems only partly from the number of changes that can be expected to take place at nuclear power plants–changes that individually have only a moderate to minor impact on the PRA, but whose combined impact is substantial and necessitates a PRA update. Additionally, a comparison of two generations of PRAs performed about 5 years apart indicates that PRAs must be periodically updated to reflect the evolution of PRA methods. The most desirable updating interval depends on these two technical considerations as well as the cost of updating the PRA. (Cost considerations, however, were beyond the scope of this study.)  相似文献   
28.
29.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
30.
Assessing reoffense risk with juvenile sexual offenders   总被引:1,自引:0,他引:1  
This article summarizes a two-year study of juvenile sexual offenders in Washington. Both community-based and institution-based treatment programs were evaluated. A typical profile of the juvenile sexual offender is offered, as well as recidivism data from a mean 20-month follow-up period.  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