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   3269篇
  免费   114篇
管理学   579篇
民族学   25篇
人才学   4篇
人口学   229篇
丛书文集   18篇
理论方法论   359篇
综合类   23篇
社会学   1649篇
统计学   497篇
  2023年   25篇
  2022年   13篇
  2021年   15篇
  2020年   59篇
  2019年   95篇
  2018年   88篇
  2017年   108篇
  2016年   103篇
  2015年   79篇
  2014年   90篇
  2013年   520篇
  2012年   120篇
  2011年   95篇
  2010年   98篇
  2009年   100篇
  2008年   110篇
  2007年   96篇
  2006年   117篇
  2005年   136篇
  2004年   94篇
  2003年   99篇
  2002年   95篇
  2001年   76篇
  2000年   55篇
  1999年   62篇
  1998年   54篇
  1997年   35篇
  1996年   39篇
  1995年   27篇
  1994年   51篇
  1993年   46篇
  1992年   39篇
  1991年   47篇
  1990年   41篇
  1989年   34篇
  1988年   34篇
  1987年   36篇
  1986年   25篇
  1985年   45篇
  1984年   44篇
  1983年   30篇
  1982年   31篇
  1981年   20篇
  1980年   14篇
  1979年   16篇
  1978年   16篇
  1977年   16篇
  1976年   15篇
  1975年   12篇
  1974年   18篇
排序方式: 共有3383条查询结果,搜索用时 31 毫秒
221.
Gender, Race, and Perception of Environmental Health Risks   总被引:17,自引:2,他引:17  
This paper reports the results of a national survey in which perceptions of environmental health risks were measured for 1275 white and 214 nonwhite persons. The results showed that white women perceived risks to be much higher than did white men, a result that is consistent with previous studies. However, this gender difference was not true of nonwhite women and men, whose perceptions of risk were quite similar. Most striking was the finding that white males tended to differ from everyone else in their attitudes and perceptions–on average, they perceived risks as much smaller and much more acceptable than did other people. These results suggest that sociopolitical factors such as power, status, alienation, and trust are strong determiners of people's perception and acceptance of risks.  相似文献   
222.
Driven by differing statutory mandates and programmatic separation of regulatory responsibilities between federal, state, and tribal agencies, distinct chemical and radiation risk management strategies have evolved. In the field this separation poses real challenges since many of the major environmental risk management decisions we face today require the evaluation of both types of risks. Over the last decade, federal, state, and tribal agencies have continued to discuss their different approaches and explore areas where their activities could be harmonized. The current framework for managing public exposures to chemical carcinogens has been referred to as a "bottom up approach." Risk between 10(-4) and 10(-6) is established as an upper bound goal. In contrast, a "top down" approach that sets an upper bound dose limit and couples with site specific As Low As Reasonably Achievable Principle (ALARA), is in place to manage individual exposure to radiation. While radiation risk are typically managed on a cumulative basis, exposure to chemicals is generally managed on a chemical-by-chemical, medium-by-medium basis. There are also differences in the nature and size of sites where chemical and radiation contamination is found. Such differences result in divergent management concerns. In spite of these differences, there are several common and practical concerns among radiation and chemical risk managers. They include 1) the issue of cost for site redevelopment and long-term stewardship, 2) public acceptance and involvement, and 3) the need for flexible risk management framework to address the first two issues. This article attempts to synthesize key differences, opportunities for harmonization, and challenges ahead.  相似文献   
223.
In this paper we compare expectations derived from 10 different human physiologically based pharmacokinetic models for perchloroethylene with data on absorption via inhalation, and concentrations in alveolar air and venous blood. Our most interesting finding is that essentially all of the models show a time pattern of departures of predictions of air and blood levels relative to experimental data that might be corrected by more sophisticated model structures incorporating either (a) heterogeneity of the fat compartment (with respect to either perfusion or partition coefficients or both) or (b) intertissue diffusion of perchloroethylene between the fat and muscle/VRG groups. Similar types of corrections have recently been proposed to reduce analogous anomalies in the fits of pharmacokinetic models to the data for several volatile anesthetics.(17-20) A second finding is that models incorporating resting values for alveolar ventilation in the region of 5.4 L/min seemed to be most compatible with the most reliable set of perchloroethylene uptake data.  相似文献   
224.
225.
Successfully managing change in an organization is very difficult. Paul Strebel sets out a new way of doing this, based on contract theory which states that stakeholders have both an explicit and implicit individual contract with their companies. These contracts must be modified if corporate change is to proceed.The author develops five propositions about the role of contracts in change management. Change can only succeed if these five propositions are satisfied and the operational implications fully understood and implemented.  相似文献   
226.
This study outlines the results of the UK's national gambling helpline run by GamCare. The results outlined here cover the period of the first 12 months of operation (November 1997 to October 1998). The helpline received a total of 1729 calls. Of these, 51% were from problem gamblers themselves (90% male; 10% female) and a further 26% of calls were from relatives of problem gamblers. The remaining calls came from other professionals handling problem gambling cases (13%), attempted calls, e.g., people calling and then putting the phone down due to being scared of talking (4%), information requests (3%) and the media (3%). Fruit machine gambling appeared to be most problematic for the callers as a whole and for particular sub-groups such as adolescents (82%) and women (52%).  相似文献   
227.
While two-stage designs in problem gambling research are expensive and relatively difficult to execute, they have the potential to yield more accurate prevalence estimates as well as valuable additional information about gambling and problem gambling in the community. However, gains in precision are heavily dependent on the accuracy of the screening methods used and the sample sizes involved. Sound practice requires reliable information about the variances and confidence levels associated with different screens. In the spirit of contributing to the ongoing dialog about ways to improve the measurement of problem gambling, we examine several reasons to question whether the revised estimates offered by Gambino are in fact an improvement.  相似文献   
228.
229.
230.
The movement of activities earlier in the product development process requires a re-examination of the total supply network. The objective of this paper is to determine the degree of early supplier involvement (ESI) that exists between a multinational electronics company and its key suppliers, in terms of depth of integration, information exchange and buyer–supplier relationships. The paper provides insights into the strategic factors that affect the dynamics of the ESI process. The research indicates that there are considerable impediments for those participants responsible for establishing and managing the implementation of ESI. A number of strategic insights are identified that explain the existence of the impediments to the ESI process. Finally, based upon the findings a number of lessons are highlighted for organisations considering the adoption of the ESI process.  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