全文获取类型
收费全文 | 7075篇 |
免费 | 233篇 |
专业分类
各国政治 | 353篇 |
工人农民 | 233篇 |
世界政治 | 549篇 |
外交国际关系 | 266篇 |
法律 | 4159篇 |
中国政治 | 53篇 |
政治理论 | 1625篇 |
综合类 | 70篇 |
出版年
2020年 | 82篇 |
2019年 | 126篇 |
2018年 | 168篇 |
2017年 | 160篇 |
2016年 | 160篇 |
2015年 | 122篇 |
2014年 | 133篇 |
2013年 | 771篇 |
2012年 | 173篇 |
2011年 | 178篇 |
2010年 | 162篇 |
2009年 | 174篇 |
2008年 | 173篇 |
2007年 | 174篇 |
2006年 | 198篇 |
2005年 | 161篇 |
2004年 | 158篇 |
2003年 | 165篇 |
2002年 | 161篇 |
2001年 | 218篇 |
2000年 | 179篇 |
1999年 | 163篇 |
1998年 | 97篇 |
1997年 | 94篇 |
1996年 | 68篇 |
1995年 | 77篇 |
1994年 | 75篇 |
1993年 | 82篇 |
1992年 | 118篇 |
1991年 | 150篇 |
1990年 | 130篇 |
1989年 | 143篇 |
1988年 | 130篇 |
1987年 | 150篇 |
1986年 | 138篇 |
1985年 | 146篇 |
1984年 | 134篇 |
1983年 | 137篇 |
1982年 | 100篇 |
1981年 | 94篇 |
1980年 | 89篇 |
1979年 | 94篇 |
1978年 | 75篇 |
1977年 | 58篇 |
1976年 | 66篇 |
1975年 | 61篇 |
1974年 | 69篇 |
1973年 | 67篇 |
1972年 | 55篇 |
1969年 | 56篇 |
排序方式: 共有7308条查询结果,搜索用时 0 毫秒
21.
22.
Correlation between plasma and bone marrow tricyclic antidepressants has not been studied before. Two groups of rabbits were given 10 and 20 mg of desipramine/kg body weight, respectively. Desipramine was administered to the animals once daily by mouth for 5 days. On the fifth day the animals were sacrificed and blood and bone marrow samples were collected and analyzed using a high performance liquid chromatographic (HPLC) method. Data showed that a correlation exists between bone marrow and blood desipramine. The bone marrow desipramine concentration increased as its blood levels increased. The average ratio of bone marrow to blood desipramine +/- S.D. (standard deviation) in both dosage groups was 37.2 +/- 4.46 with a range of 30.99-44.82. This investigation is promising and shows that bone marrow could be used as an alternative tissue in the absence of a suitable blood sample. 相似文献
23.
W D Haglund D G Reichert D T Reay 《The American journal of forensic medicine and pathology》1990,11(1):35-43
The Green River Murder Investigation in King County, Washington, is currently the longest active serial murder investigation in U.S. history. During its course, over 26 separate scenes with from one to five victims each have been processed. The experience of the authors is presented in order to acquaint other agencies with techniques of outdoor scene processing that have evolved during recovery of remains from Green River and other skeletal cases. 相似文献
24.
J W Eisele J Frisino W Haglund D T Reay 《The American journal of forensic medicine and pathology》1987,8(3):208-209
The population-adjusted rate of teenage suicide in King County, Washington, was reviewed for the 26 years from 1959 to 1984. For the entire period, the rate did not change significantly. An abrupt change did occur during the middle of this period, but, for reasons discussed in the text, this may well represent a change in procedures and philosophy of death certification rather than a real change in rate. Reasons for the apparent discrepancy with national statistics are discussed. 相似文献
25.
David Brady Yunus Kaya Jason Beckfield 《Studies in Comparative International Development (SCID)》2007,42(1-2):1-35
Development debates have been greatly influenced by the growth consensus: the conventional wisdom that economic growth should be the primary priority for less-developed countries (LDCs) because it most effectively improves the well-being of the world’s poor. We compare the impact of growth to other independent variables in an unbalanced panel analysis of up to 109 LDCs and 580 observations across six time points (1980, 1985, 1990, 1995, 2000, and 2003). Our dependent variables include caloric consumption, infant survival probability, one-to-five year survival probability, female life expectancy, and male life expectancy. First, we find that gross domestic product (GDP) has significant positive effects on caloric consumption, female life expectancy, and male life expectancy. Second, GDP does not have robust effects on infant and one-to-five survival probabilities. Third, fertility, urbanization, and secondary school enrollment have larger effects than GDP in the majority of models. The more powerful effects of fertility, urbanization, and secondary schooling cannot simply be attributed to an indirect effect of GDP. Fourth, we find that dependency variables do not have robust significant effects. Fifth, over time, GDP has become much less effective at improving caloric consumption and infant and one-to-five survival. We infer that there are serious limitations to concentrating exclusively on economic growth to improve well-being in LDCs. 相似文献
26.
In the statistical interpretation of forensic glass evidence it is standard practice to make the assumption of homogeneity of the refractive index (RI) of the source glass, or of localized homogeneity. However, the work of Locke and Hayes showed that, for toughened windscreen glass, this assumption might not be true. This work is well cited, but there appears to have been little follow-on published research. Furthermore, the toughening process is something known to affect the refractive index, and is a process that float glass does not undergo. Float glass is a major component of casework in New Zealand and for that reason it would be interesting to know whether the findings of Locke and Hayes apply when dealing with float glass. In this paper we describe an experiment similar to that of Locke and Hayes, systematically examining the variation of RI in a pane of float window glass. It was found that, although there were no systematic differences in refractive index, there were observable differences across the pane. 相似文献
27.
28.
Report of an unusual finding of bones on the shore of the Baltic Sea. Although the morphological findings appeared similar to a human foot skeleton, a quick identification as sea dog bone was possible. 相似文献
29.
C Moore S Browne I Tebbett A Negrusz W Meyer L Jain 《Forensic science international》1992,56(2):177-181
A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers. 相似文献
30.