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   9490篇
  免费   306篇
各国政治   626篇
工人农民   365篇
世界政治   746篇
外交国际关系   386篇
法律   5390篇
中国共产党   2篇
中国政治   140篇
政治理论   2038篇
综合类   103篇
  2020年   124篇
  2019年   143篇
  2018年   205篇
  2017年   230篇
  2016年   229篇
  2015年   199篇
  2014年   205篇
  2013年   1145篇
  2012年   240篇
  2011年   325篇
  2010年   236篇
  2009年   252篇
  2008年   256篇
  2007年   237篇
  2006年   236篇
  2005年   208篇
  2004年   229篇
  2003年   245篇
  2002年   180篇
  2001年   369篇
  2000年   339篇
  1999年   309篇
  1998年   157篇
  1997年   117篇
  1996年   118篇
  1995年   110篇
  1994年   113篇
  1993年   112篇
  1992年   167篇
  1991年   164篇
  1990年   151篇
  1989年   142篇
  1988年   165篇
  1987年   165篇
  1986年   169篇
  1985年   151篇
  1984年   151篇
  1983年   161篇
  1982年   99篇
  1981年   70篇
  1980年   82篇
  1979年   103篇
  1978年   84篇
  1977年   68篇
  1976年   70篇
  1975年   63篇
  1973年   55篇
  1972年   56篇
  1971年   61篇
  1969年   58篇
排序方式: 共有9796条查询结果,搜索用时 31 毫秒
201.
202.
In 1989, after almost two decades of substance-by-substance standard setting, the Occupational Safety and Health Administration (OSHA) promulgated its Air Contaminants Standard, imposing new exposure limits for 376 toxic substances encountered in U.S. industry. In marked contrast to earlier regulations, the Air Contaminants Standard has generated relatively little industry opposition. This paper analyzes the standard in the context of the twenty-year debate over the appropriate role for technological feasibility and economic compliance costs in occupational health policy. The political feasibility of the new standard is traced to OSHA's abandonment of "technology forcing" in favor of reliance on "off-the-shelf" technologies already in use in major firms. While important as an embodiment of OSHA's new "generic" approach to regulation, the Air Contaminants Standard cannot serve as a model for future occupational health policy, due to its reliance on informal, closed-door mechanisms for establishing regulatory priorities and permissible exposure limits.  相似文献   
203.
204.
In Summit Health Ltd. v. Pinhas, the United States Supreme Court by a narrow majority found that the exclusion of an ophthalmologist from a hospital in Los Angeles had a sufficient effect on interstate commerce to establish federal jurisdiction under the Sherman Act. In resolving a split among the federal circuit courts of appeal, the Court applied the broad jurisdictional test from McLain v. Real Estate Board of New Orleans, Inc. to peer review proceedings. Despite many ambiguities in the majority opinion by Justice Stevens and a scathing dissent by Justice Scalia, the effect of Pinhas will be to increase the suits in federal court on antitrust grounds brought by aggrieved medical staff members and applicants denied appointments or privileges, and to decrease, if not eliminate, the likelihood of preliminary dismissal on jurisdictional grounds. This, in turn, should serve to emphasize the importance of complying with the Health Care Quality Improvement Act in order to obtain immunity from damages under federal antitrust and state laws.  相似文献   
205.
206.
207.
208.
Child mortality was analyzed in relation to 3 dimensions of reproductive behavior: birth intervals, additional children desired, and contraceptive use. Study data were drawn from a 1978 survey conducted in 2 predominantly rural governorates, Beheira and Kafr El-Sheikh, in lower Egypt. Within each governorate, 2 districts were selected on the basis of their distance from the capital of the governorate, agricultural output by major crops, percent of the population urban, infant mortality rate, and crude birthrate. Within each of the 4 districts, villages were randomly drawn from 3 strata: villages lacking any governmental services; villages with limited services (health center or primary school); and villages served by a combined unit center providing integrated services. A random sample of household heads was selected from household registration records of the provision office of each district. 1200 interviews were obtained from 685 households. Restriction of the sample to women with 1 or more live births, and the elimination of 13 cases with incomplete or inaccurate information, yielded 1010 cases for analysis. The basic measure of actual fertility was birth intervals. For the total sample and within each age category, cumulative fertility is higher the greater the number of child deaths. The data demonstrate a strong relationship between child mortality experience and cumulative fertility. The problem lies in interpreting such results. With some exceptions, birth intervals increased as expected with increasing parity. Women without child death experience displayed longer birth intervals than women who had not lost a child. With the single exception of the 7th parity women, all differences were statistically significant. The data fail to eliminate potential biological influences on subsequent fertility. With biological influences adequately controlled, no behavioral differences remained. Women who experienced child mortality desired greater numbers of additional children than women without child death experience. 19% of respondents were ever users of contraception, with women of low parity the least likely ever to have used contraception.  相似文献   
209.
210.
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