全文获取类型
收费全文 | 6103篇 |
免费 | 221篇 |
专业分类
各国政治 | 427篇 |
工人农民 | 181篇 |
世界政治 | 617篇 |
外交国际关系 | 440篇 |
法律 | 2551篇 |
中国政治 | 50篇 |
政治理论 | 1987篇 |
综合类 | 71篇 |
出版年
2023年 | 41篇 |
2022年 | 28篇 |
2021年 | 54篇 |
2020年 | 103篇 |
2019年 | 149篇 |
2018年 | 166篇 |
2017年 | 194篇 |
2016年 | 199篇 |
2015年 | 115篇 |
2014年 | 172篇 |
2013年 | 1026篇 |
2012年 | 170篇 |
2011年 | 174篇 |
2010年 | 173篇 |
2009年 | 180篇 |
2008年 | 157篇 |
2007年 | 218篇 |
2006年 | 190篇 |
2005年 | 225篇 |
2004年 | 227篇 |
2003年 | 209篇 |
2002年 | 225篇 |
2001年 | 120篇 |
2000年 | 115篇 |
1999年 | 97篇 |
1998年 | 90篇 |
1997年 | 92篇 |
1996年 | 89篇 |
1995年 | 92篇 |
1994年 | 93篇 |
1993年 | 78篇 |
1992年 | 84篇 |
1991年 | 91篇 |
1990年 | 62篇 |
1989年 | 65篇 |
1988年 | 64篇 |
1987年 | 63篇 |
1986年 | 67篇 |
1985年 | 62篇 |
1984年 | 53篇 |
1983年 | 62篇 |
1982年 | 48篇 |
1981年 | 55篇 |
1980年 | 38篇 |
1979年 | 37篇 |
1978年 | 32篇 |
1977年 | 33篇 |
1976年 | 30篇 |
1974年 | 15篇 |
1967年 | 14篇 |
排序方式: 共有6324条查询结果,搜索用时 15 毫秒
31.
32.
33.
David DeGrazia 《The Journal of law, medicine & ethics》2006,34(1):49-57
Underlying President Bush's view regarding stemcell research and cloning are two assumptions: we originate at conception, and we have full moral status as soon as we originate. I will challenge both assumptions, argue that at least the second is mistaken, and conclude that the President's approach is unsustainable. 相似文献
34.
35.
36.
37.
David P. Colvin 《The Journal of Technology Transfer》1995,20(2):5-7
Historically, small businesses have been the innovation engine of the United States, with significantly more than half of the new technologies and products coming from small enterprises. In 1992, there were more than 21 million small businesses with fewer than 500 employees each in the United States, including 4.5 million small corporations, 1.6 million partnerships, and 15.1 million sole proprietorships. Although most small businesses have considerably fewer than 100 employees, they employ more than half the private U.S. work force, contribute more than half of all sales in the country, and are responsible for over half of the private sector's products. From 1976 to 1990, small firms also generated 65% of the net new jobs. From 1988 to 1990, all of the net new jobs in the U.S. economy were created by small firms. Indeed, small business is really big business in the United States. 相似文献
38.
39.
Sixteen major evaluations of programs to prevent school bullying, conducted in 11 different countries, are reviewed in detail. Of these 16 evaluations, 8 produced desirable results, 2 produced mixed results, 4 produced small or negligible effects, and 2 produced undesirable results. These varying findings may reflect variations in programs, in implementation, in assessment methods, or in evaluation designs. It is concluded that high-quality evaluations are needed in the future, with randomized designs, theoretically grounded interventions, multiple measures of bullying, and attempts to disentangle the effectiveness of different program components. 相似文献
40.