全文获取类型
收费全文 | 6939篇 |
免费 | 291篇 |
国内免费 | 3篇 |
专业分类
各国政治 | 371篇 |
工人农民 | 57篇 |
世界政治 | 892篇 |
外交国际关系 | 863篇 |
法律 | 2673篇 |
中国共产党 | 541篇 |
中国政治 | 892篇 |
政治理论 | 462篇 |
综合类 | 482篇 |
出版年
2023年 | 46篇 |
2022年 | 50篇 |
2021年 | 43篇 |
2020年 | 46篇 |
2019年 | 56篇 |
2018年 | 72篇 |
2017年 | 16篇 |
2016年 | 41篇 |
2015年 | 54篇 |
2014年 | 238篇 |
2013年 | 165篇 |
2012年 | 432篇 |
2011年 | 454篇 |
2010年 | 277篇 |
2009年 | 244篇 |
2008年 | 344篇 |
2007年 | 354篇 |
2006年 | 390篇 |
2005年 | 318篇 |
2004年 | 319篇 |
2003年 | 316篇 |
2002年 | 321篇 |
2001年 | 239篇 |
2000年 | 202篇 |
1999年 | 139篇 |
1998年 | 113篇 |
1997年 | 116篇 |
1996年 | 101篇 |
1995年 | 117篇 |
1994年 | 119篇 |
1993年 | 77篇 |
1992年 | 65篇 |
1991年 | 96篇 |
1990年 | 71篇 |
1989年 | 72篇 |
1988年 | 115篇 |
1987年 | 89篇 |
1986年 | 88篇 |
1985年 | 104篇 |
1984年 | 101篇 |
1983年 | 99篇 |
1982年 | 69篇 |
1981年 | 68篇 |
1980年 | 91篇 |
1979年 | 46篇 |
1973年 | 17篇 |
1964年 | 22篇 |
1962年 | 19篇 |
1959年 | 18篇 |
1957年 | 17篇 |
排序方式: 共有7233条查询结果,搜索用时 0 毫秒
261.
262.
263.
Determination of formic acid tissue and fluid concentrations in three fatalities due to methanol poisoning 总被引:1,自引:0,他引:1
Hantson P Haufroid V Mahieu P 《The American journal of forensic medicine and pathology》2000,21(4):335-338
Three fatalities caused by methanol ingestion are reported. Admission blood methanol concentrations ranged from 0.28 to 4.6 g/L. Two patients had been admitted after a significant delay (>20 hours), and one patient was observed within 90 minutes following ingestion. Formic acid levels were determined in blood samples at admission and ranged from 302 to 680 mg/L. The patients died 44, 55, and 82 hours after poisoning. Formic acid determinations in postmortem tissues were performed by a gas chromatograph method. The authors found great variability in formic acid distribution among the patients and among organs. 相似文献
264.
265.
Forensic psychiatric services in British Columbia 总被引:1,自引:0,他引:1
266.
267.
Beyleveld D 《Forensic science international》2000,113(1-3):461-475
The legal position in the UK on embryo research and preimplantation genetic diagnosis (PGD) is outlined and contrasted with the position in other EU countries. The "gradualist" position of the UK on the moral status of the embryo is defended on the basis of an argument that precaution must be applied in proportion to the degree to which the embryo has developed to display components of agency, on the assumption that mortality is categorically binding and requires agents to be granted rights and that it cannot be known with certainty that the embryo is not an agent. The extent to which this argument, when combined with vicarious protections that the embryo should receive in order to protect the rights of other agents, limits embryo research and PGD, is discussed. It is concluded that the complexities that attend deliberation about the moral problems attending embryo research and PGD are such that the proper response to these problems is via the procedures of political democracy to achieve accountable answers rather than "correct" answers. This allows for a variety of judgements. 相似文献
268.
Automated analysis of fire residues involves a strategy which deals with the wide variety of received criminalistic samples. Because of unknown concentration of accelerant in a sample and the wide range of flammable products, full attention from the analyst is required. Primary detection with a photoionisator resolves the first problem, determining the right method to use: the less responsive classical head-space determination or absorption on active charcoal tube, a better fitted method more adapted to low concentrations can thus be chosen. The latter method is suitable for automatic thermal desorption (ATD400), to avoid any risk of cross contamination. A PONA column (50 mx0.2 mm i.d.) allows the separation of volatile hydrocarbons from C(1) to C(15) and the update of a database. A specific second column is used for heavy hydrocarbons. Heavy products (C(13) to C(40)) were extracted from residues using a very small amount of pentane, concentrated to 1 ml at 50 degrees C and then placed on an automatic carousel. Comparison of flammables with referenced chromatograms provided expected identification, possibly using mass spectrometry. This analytical strategy belongs to the IRCGN quality program, resulting in analysis of 1500 samples per year by two technicians. 相似文献
269.
270.
近几年来美国把对泰国援助中一部分“贈欵”改为貸欵,泰报认为是援助減少了。作者认为貸欵也是援助,但可能使泰国经济发展計划降低要求或中止,言外之音是希望增加“贈欵”。 相似文献