全文获取类型
收费全文 | 7617篇 |
免费 | 493篇 |
专业分类
各国政治 | 369篇 |
工人农民 | 299篇 |
世界政治 | 499篇 |
外交国际关系 | 259篇 |
法律 | 5248篇 |
中国政治 | 40篇 |
政治理论 | 1357篇 |
综合类 | 39篇 |
出版年
2020年 | 166篇 |
2019年 | 173篇 |
2018年 | 189篇 |
2017年 | 224篇 |
2016年 | 234篇 |
2015年 | 207篇 |
2014年 | 189篇 |
2013年 | 815篇 |
2012年 | 169篇 |
2011年 | 184篇 |
2010年 | 220篇 |
2009年 | 233篇 |
2008年 | 179篇 |
2007年 | 178篇 |
2006年 | 184篇 |
2005年 | 172篇 |
2004年 | 199篇 |
2003年 | 171篇 |
2002年 | 146篇 |
2001年 | 319篇 |
2000年 | 259篇 |
1999年 | 235篇 |
1998年 | 108篇 |
1997年 | 74篇 |
1996年 | 78篇 |
1995年 | 84篇 |
1994年 | 98篇 |
1993年 | 98篇 |
1992年 | 162篇 |
1991年 | 168篇 |
1990年 | 159篇 |
1989年 | 160篇 |
1988年 | 132篇 |
1987年 | 138篇 |
1986年 | 126篇 |
1985年 | 137篇 |
1984年 | 107篇 |
1983年 | 122篇 |
1982年 | 87篇 |
1981年 | 79篇 |
1980年 | 59篇 |
1979年 | 113篇 |
1978年 | 70篇 |
1977年 | 60篇 |
1976年 | 51篇 |
1975年 | 51篇 |
1974年 | 56篇 |
1973年 | 55篇 |
1972年 | 45篇 |
1968年 | 40篇 |
排序方式: 共有8110条查询结果,搜索用时 15 毫秒
761.
762.
763.
L.B. Curzon 《The Law teacher》2013,47(1):32-36
“Health” is a disciplinarily imperialistic and conceptually amorphous term; as such, it defies a unifying, coherent and universal definition. These characteristics of health present enormous problems for a curriculum developer trying to chart the outlines and contents of the subject. A sure way out is to reflect carefully on Gardner's suggestion regarding the tension between depth and coverage and to make the definition of health a part of any module on health care law. In addition, the experiences of other common jurisdictions present Nigeria with a choice between a single module approach and multiple module approach to health care law. 相似文献
764.
Davis B. Bobrow 《国际研究展望》2001,2(1):1-12
This essay was stimulated (provoked) by discussions in three separate venues: (1) a U.S. Naval War College conference on "Alternative Futures in War and Conflict: Implications for U.S. National Security," held in late 1999; (2) several recent widely circulated "blue-ribbon" reports on the subject; and (3) recent papers emerging from the U.S. defense bureaucracy speculating on strategic visions of the next ten to twenty years. My contention is that the prevailing official and quasi-official debate exhibits excessive and overly definitive emphases on: (1) particular facets of insecurity; (2) attributions to the U.S. of benign intent and capacity; and (3) assumptions that most others share that interpretation of our words and deeds. There also tends to be unwarranted neglect of representation and standing issues which discriminate for and against different policy perspectives and forms of program expertise. A plea is offered for an alternative approach based on what we know about how persons, organizations, and communities can best position themselves for (in)security futures. 相似文献
765.
766.
767.
768.
769.
770.
A novel method for the forensic analysis of commercial petroleum products is presented. In this approach, the petroleum sample is extracted with nitromethane and then separated by capillary liquid chromatography with laser-induced fluorescence detection. The addition of selective fluorescence quenching agents allows the sample to be profiled by the distribution of alternant and nonalternant polycyclic aromatic hydrocarbons (PAHs). In preliminary studies, the quenching behavior of nitromethane and diisopropylamine was established by using a standard mixture of sixteen PAHs ranging in size from two to six aromatic rings. Subsequent examination of new and used motor oil demonstrated that characteristic differences arise in the PAH content, which may allow for the unique identification of oil from a particular engine or vehicle. In addition, three brands of petrolatum jelly were successfully distinguished. Although a number of alternant alkylated and heterocyclic PAHs were found in all petrolatum samples, there were significant differences in the relative concentrations of alternant as well as nonalternant PAHs. This allowed for clear differentiation of the samples through qualitative inspection of their chromatograms as well as quantitative statistical correlation techniques. 相似文献