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   22019篇
  免费   431篇
  国内免费   1篇
管理学   2964篇
民族学   129篇
人才学   1篇
人口学   1919篇
丛书文集   96篇
教育普及   1篇
理论方法论   1941篇
综合类   209篇
社会学   11116篇
统计学   4075篇
  2023年   138篇
  2022年   99篇
  2021年   142篇
  2020年   365篇
  2019年   538篇
  2018年   652篇
  2017年   849篇
  2016年   653篇
  2015年   436篇
  2014年   612篇
  2013年   3940篇
  2012年   785篇
  2011年   759篇
  2010年   559篇
  2009年   464篇
  2008年   590篇
  2007年   560篇
  2006年   570篇
  2005年   465篇
  2004年   474篇
  2003年   401篇
  2002年   410篇
  2001年   505篇
  2000年   451篇
  1999年   440篇
  1998年   355篇
  1997年   310篇
  1996年   321篇
  1995年   334篇
  1994年   279篇
  1993年   301篇
  1992年   344篇
  1991年   338篇
  1990年   327篇
  1989年   283篇
  1988年   266篇
  1987年   234篇
  1986年   250篇
  1985年   278篇
  1984年   245篇
  1983年   228篇
  1982年   186篇
  1981年   157篇
  1980年   181篇
  1979年   195篇
  1978年   166篇
  1977年   130篇
  1976年   111篇
  1975年   111篇
  1974年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
The extent of carcinogen regulation under existing U.S. environmental statutes is assessed by developing measures of the scope and stringency of regulation. While concern about cancer risk has played an important political role in obtaining support for pollution control programs, it has not provided the predominant rationale for most regulatory actions taken to date. Less than 20% of all standards established to limit concentrations of chemicals in various media address carcinogens. Restrictions on chemical use are more frequently based on concerns about noncancer human health or ecological effects. Of the chemicals in commercial use which have been identified as potential human carcinogens on the basis of rodent bioassays, only a small proportion are regulated. There is an inverse relationship between the scope of regulatory coverage and the stringency of regulatory requirements: the largest percentages of identified carcinogens are affected by the least stringent requirements, such as information disclosure. Standards based on de minimis cancer risk levels have been established for only 10% of identified carcinogens and are restricted to one medium: water. Complete bans on use have affected very few chemicals. The general role that carcinogenicity now plays in the regulatory process is not dramatically different from that of other adverse human health effects: if a substance is identified as a hazard, it may eventually be subject to economically achievable and technically feasible restrictions.  相似文献   
102.
This paper presents a case study of the August 1994 Cuban balseros crisis, during which more than 35,000 fled the island and headed toward Florida in the span of a few weeks. It argues that Castro launched the crisis in an attempt to manipulate US fears of another Mariel, and in order to compel a shift in US policy, both on immigration and on a wider variety of issues. The paper further contends that from Castro’s perspective, this exercise in coercion proved a qualified success – his third such successful use of the Cuban people as an asymmetric political weapon against the US. In addition, the paper argues that Castro’s success was predicated on his ability to internationalize his own domestic crisis and transform it into an American domestic political and foreign policy crisis. Finally, it offers a novel explanation of how, why, and under what conditions, states and/or non–state actors may attempt to use refugees as coercive political weapons. Although dwarfed in size by the larger 1980 Mariel boatlift, the 1994 crisis is important for several reasons. First, despite its brevity, it had far reaching consequences for US–Cuban relations. Without warning or preamble, it catalyzed a shift in US policy vis–à–vis Cuban immigration that represented a radical departure from what it had been for the previous three decades. Second, it influenced US domestic politics on the national level, by expanding the scope and salience of the issue, and mobilizing not only Floridians, but also the larger public concerned about illegal immigration. Third, the crisis illustrated the potential potency of engineered migration as an asymmetric weapon of the weak. Finally, the brief, but significant, interactions of international and domestic actors in this case warrant examination because, although the 1994 crisis was limited, in its dynamics it resembles myriad other international refugee crises, large and small. Thus the case offers valuable lessons that may aid in dealing with future (real or threatened) crises.  相似文献   
103.
Abstract Although scholars cite the Tennessee Valley Authority as one of President Franklin Roosevelt's major reform programs, the valley authority model did not replace the limited‐purpose water programs of the Bureau of Reclamation and the Army Corps of Engineers. State‐centered theorists hold that reformers are most likely to succeed during periods such as the New Deal era, when they are supported by a democratized polity and when they dominate Congress and the administration. This paper shows that in river policy, the strength of opposing interest groups also mattered. The TVA bill was passed in 1933 because reformers skillfully coordinated action at potential choke points and weakened the already disorganized opposing lobbyists. In 1936, however, after regrouping, opposing river lobbyists and legislators took advantage of the New Dealers' spending mood by expanding the Corps' flood control program. They also helped defeat further valley authorities, the most promising of the New Deal water policy reforms.  相似文献   
104.
Extractive industries such as logging and mining are generally expected to bring significant economic benefits to rural regions, but a growing number of findings have now challenged that common expectation. Still, it is not clear whether the findings of less–than–desirable economic outcomes are isolated or representative. In this article, we assemble literally all of the relevant quantitative findings on mining that we have been able to identify in published and/or technical literature from the United States. In the interest of rigor, we limit the assessment to cases in which strictly nonmetropolitan mining regions are compared against other nonmetropolitan regions and/or against those regions’ own experiences over time. Overall, 301 findings meet the criteria for inclusion. Contrary to the long–established assumptions, but consistent with more recent critiques, roughly half of all published findings indicate negative economic outcomes in mining communities, with the remaining findings being split roughly evenly between favorable and neutral/indeterminate ones. Positive findings are more likely to be associated with incomes than with poverty or (especially) unemployment rates, and they are more likely to come from the western United States, where much of the mining involves relatively large, new coal strip mines. Over half of all positive findings come from the years prior to 1982. In virtually all other categories, the plurality or majority of findings have been negative. When the patterns of findings are subjected to one–sample means tests, the only way to produce a significantly positive outcome is by combining all neutral/indeterminate findings with the positive ones, while focusing exclusively on incomes; by contrast, in the case of poverty or unemployment rates—as well as for the overall body of findings—the results are consistently and significantly negative, whether the neutral/indeterminate findings are combined with negative ones or omitted from the equations altogether. Until or unless future studies produce dramatically different findings, there appears to be no scientific basis for accepting the widespread, “obvious” assumption that mining will lead to economic improvement.  相似文献   
105.
Acknowledgment of outside reviewers for 1994  相似文献   
106.
Data from the 1988 National Survey on Families and Households were analyzed to examine the associations among marital conflict, ineffective parenting, and children's and adolescents' maladjustment. Parents' use of harsh discipline and low parental involvement helped explain the connection between marital conflict and children's maladjustment in children aged 2 through 11. Parent‐child conflict was measured only in families with a target teenager and also was a significant mediator. Although ineffective parenting explained part of the association between marital conflict and children's maladjustment, independent effects of marital conflict remained in families with target children aged 2 through 11 (but not for families with a teenager). With a few exceptions, this pattern of findings was consistent for mothers' and fathers' reports, for daughters and sons, for families with various ethnic backgrounds, and for families living in and out of poverty.  相似文献   
107.
A strategy of analyzing the moral vocabulary of a social movement or subculture is proposed by which ethnographies and other qualitative works may place the moral and ethical concepts used by respondents into a broader sociological context. Through examining the moral resources, the status hierarchy which the specific moral resources within a given moral vocabulary form, and the historical and cultural contexts within which these moral resources exist, it is argued that it becomes possible to analyze and anticipate the moral claims and form of discourse which will be produced by a specific movement and/or subculture. It is also argued that this method may be used to predict how the opposition to a movement and/or subculture is perceived through the formation of an antithetical moral vocabulary.  相似文献   
108.
In this article, the authors present a case example of a Chinese American lesbian woman who seeks counseling for career decision making. The client's career issues stem from cultural issues that have created a dichotomy in her life. Using an ecological model, the authors dissect the case, propose interventions, and identify potential problems that may arise.  相似文献   
109.
The development and initial psychometric properties of an adolescent gambling problem severity measure are described. The scale, based on a revision of the South Oaks Gambling Screen (Lesieur & Blume, 1987), was administered to 1,101 older (ages 15 to 18) Minnesota adolescents as part of a state-wide gambling survey. Study results indicated that the scale had moderate internal consistency reliability and was significantly related to alternate measures of problem severity for male subjects. Because the rate and severity of gambling among females was very low, the psychometric adequacy of the scale for females is not known at this time. The implications of study findings to the conceptual understanding of adolescent gambling problem severity as well as study limitations and future research needs, are discussed.Support for the study was provided by the Minnesota Department of Human Services and the Center for Addiction Studies, University of Minnesota, Duluth. The authors gratefully acknowledge the assistance from Robert Blum, Linda Harris, Durand Jacobs, J. Laundergan, Alan Mathiason, Brenda Miller, James Schaefer, school officials from the participating high schools, and interviewers who assisted with the telephone survey.  相似文献   
110.
The issue of work place hazards that may threaten the health of an unborn child has long been problematic for women, business decision-makers, and lawmakers. The desire to protect the developing foetus must be balanced against a woman's legal right to get and keep the job of her choice. The issue has never been easy to resolve, as this historical analysis shows. An overview of the potential effects of work place hazards on reproductive health is presented. Relevant fair employment laws are summarized, and a brief history of court cases and employer practices is provided. It is argued that ultimately, foetal protection policies had little or nothing to do with protection of foetuses. They may have had more to do with protecting the employer from potential liability and with perceptions of women's status in the work place than with protecting the next generation. Finally, suggestions for future research are presented.  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