全文获取类型
收费全文 | 3643篇 |
免费 | 64篇 |
专业分类
各国政治 | 110篇 |
工人农民 | 105篇 |
世界政治 | 163篇 |
外交国际关系 | 101篇 |
法律 | 2765篇 |
中国政治 | 19篇 |
政治理论 | 393篇 |
综合类 | 51篇 |
出版年
2020年 | 37篇 |
2019年 | 36篇 |
2018年 | 62篇 |
2017年 | 48篇 |
2016年 | 70篇 |
2015年 | 35篇 |
2014年 | 57篇 |
2013年 | 287篇 |
2012年 | 96篇 |
2011年 | 141篇 |
2010年 | 83篇 |
2009年 | 68篇 |
2008年 | 114篇 |
2007年 | 131篇 |
2006年 | 117篇 |
2005年 | 88篇 |
2004年 | 130篇 |
2003年 | 124篇 |
2002年 | 116篇 |
2001年 | 152篇 |
2000年 | 139篇 |
1999年 | 104篇 |
1998年 | 22篇 |
1997年 | 20篇 |
1995年 | 19篇 |
1993年 | 30篇 |
1992年 | 62篇 |
1991年 | 85篇 |
1990年 | 86篇 |
1989年 | 91篇 |
1988年 | 96篇 |
1987年 | 89篇 |
1986年 | 76篇 |
1985年 | 77篇 |
1984年 | 68篇 |
1983年 | 61篇 |
1982年 | 25篇 |
1981年 | 22篇 |
1979年 | 31篇 |
1978年 | 34篇 |
1977年 | 24篇 |
1976年 | 29篇 |
1975年 | 29篇 |
1974年 | 38篇 |
1973年 | 37篇 |
1972年 | 38篇 |
1971年 | 37篇 |
1970年 | 38篇 |
1969年 | 32篇 |
1968年 | 27篇 |
排序方式: 共有3707条查询结果,搜索用时 375 毫秒
391.
392.
Deoxyribonucleic acid (DNA) isolated from male and female fresh blood samples was processed exactly as for routine DNA fingerprint analysis; that is, the DNA was digested with particular restriction endonucleases and fractionated by agarose gel electrophoresis. Ultraviolet (UV) visualization of ethidium-bromide (EtBr)-stained gels revealed a sex-specific banding pattern, which depended only on the restriction enzyme used. By means of this test, which is based on direct detection of particular sex-specific restriction fragments in human DNA digests, the authors succeeded in determining the sex of DNA obtained from biological specimens recovered as criminal evidence in rape cases. The data obtained demonstrate that direct sexing of DNA on DNA fingerprint gel appears to be useful as an intermediate control step in DNA fingerprinting analysis used for the purpose of assailant identification. 相似文献
393.
394.
Following a short-term burst of migration activity after the dissolution of the USSR, the current situation is marked by the unusually low population territorial mobility, defined by both the political and, increasingly, the socioeconomic factors. While this trend indicates some degree of minority accommodation, it also demonstrates the depth of economic crisis and increasing socioeconomic differentiation. Visible also is the disproportionate influence exercised by Russia on the formation of migration flows in the region. Remaining the major recipient of migrants, Russia increasingly plays a role of supplier of labor migrants to the West, and acts as a “bridge” for those attempting to reach Western Europe. Meanwhile, Russia still lacks an effective legislative base, institutional mechanisms, and political will for dealing with the new migration flows. 相似文献
395.
396.
397.
398.
Roxane D. V. Sismanidis 《East Asia》1996,15(2):63-80
Beijing’s weapons modernization, arms transfer, and arms control policies reflect priorities and internal and external constraints established in previous decades. Although Chinese perceptions of the evolving security environment in Asia have prompted some adjustments, PRC policies remain constricted by a security structure originally formed during the cold war, domestically driven security policymaking, and non-security factors, including economic and technological limitations imposed by the global market, the domestic economy and budgetary resources, and technological developments. Constraints notwithstanding, it is China’s policy ambiguities and opaque intentions that fuel suspicions throughout Asia that the PRC seeks to dominate the region. 相似文献
399.
400.
The introduction of a standardized paternity index (PI) for the statistical evaluation of blood group findings in cases of disputed paternity is proposed and explained. By using the PI as parameter, it is not necessary to give the information of the probability of paternity in percent. The PI includes the full information of the blood group findings. In addition to that, by using the suggested standardization based on the probabilities of error according to Schulte Mönting and Walter the test volume is also taken into account. The interpretation of the mathematical result is given by verbal predicates, the limitations of which are orientated by the verbal predicates for the probabilities of error according to Schulte Mönting and Walter, published by us elsewhere. Besides the essential fact that the test volume is taken into account, the most important advantage of this procedure is that the mathematical result is involved in the court decision only by the PI (which is free of any valuation) and its verbal predicate and not by sometimes relatively high percentages, which may be misunderstood by laymen. 相似文献