全文获取类型
收费全文 | 4336篇 |
免费 | 196篇 |
专业分类
各国政治 | 300篇 |
工人农民 | 325篇 |
世界政治 | 366篇 |
外交国际关系 | 216篇 |
法律 | 2640篇 |
中国政治 | 17篇 |
政治理论 | 649篇 |
综合类 | 19篇 |
出版年
2023年 | 44篇 |
2022年 | 22篇 |
2021年 | 66篇 |
2020年 | 94篇 |
2019年 | 126篇 |
2018年 | 250篇 |
2017年 | 228篇 |
2016年 | 271篇 |
2015年 | 150篇 |
2014年 | 176篇 |
2013年 | 525篇 |
2012年 | 272篇 |
2011年 | 210篇 |
2010年 | 82篇 |
2009年 | 83篇 |
2008年 | 118篇 |
2007年 | 130篇 |
2006年 | 114篇 |
2005年 | 460篇 |
2004年 | 192篇 |
2003年 | 107篇 |
2002年 | 70篇 |
2001年 | 60篇 |
2000年 | 45篇 |
1999年 | 38篇 |
1998年 | 24篇 |
1997年 | 14篇 |
1996年 | 12篇 |
1995年 | 19篇 |
1993年 | 13篇 |
1992年 | 30篇 |
1991年 | 33篇 |
1990年 | 35篇 |
1989年 | 43篇 |
1988年 | 33篇 |
1987年 | 34篇 |
1986年 | 32篇 |
1985年 | 24篇 |
1984年 | 20篇 |
1983年 | 17篇 |
1979年 | 11篇 |
1978年 | 11篇 |
1975年 | 16篇 |
1974年 | 28篇 |
1973年 | 15篇 |
1972年 | 22篇 |
1971年 | 21篇 |
1970年 | 15篇 |
1968年 | 12篇 |
1967年 | 12篇 |
排序方式: 共有4532条查询结果,搜索用时 15 毫秒
91.
92.
Postmortem stability of DNA 总被引:11,自引:0,他引:11
High-molecular-weight DNA was recovered postmortem in sufficient quantities from various human organ tissues as well as from blood, although not all organs were equally well suitable. Good DNA stability was found in brain cortex, lymph nodes and psoas muscle over a period of three weeks postmortem. Spleen and kidney showed good DNA stability up to five days postmortem but after longer periods, rapid degradation was observed. Yields of DNA from blood were not consistent because of the non homogeneity of samples. Blood clots were rich with DNA. Generally, the amount of degraded DNA correlated directly with the duration of the postmortem period. However in some cases, DNA degradation was already prominent after a short period. However in some cases, DNA degradation was already prominent after a short period. Case histories showed that high environmental temperature at the site of death and/or infectious diseases prior to death were the main factors for rapid autolysis. Gradual disappearance to complete loss of the long fragments (15-23 kb) was observed in DNA fingerprinting using the minisatellite probe 33.15. No extra-bands were noted, thus excluding erroneous conclusions. However, evidentiary value of older samples was lower. 相似文献
93.
Headspace gas chromatography was used to determine the concentration of ethanol and methanol in blood samples from 519 individuals suspected of drinking and driving in Sweden where the legal alcohol limit is 0.50 mg/g in whole blood (11 mmol/l). The concentration of ethanol in blood ranged from 0.01 to 3.52 mg/g with a mean of 1.83 +/- 0.82 mg/g (+/- S.D.). The frequency distribution was symmetrical about the mean but deviated from normality. A plot of the same data on normal probability paper indicated that it might be composed of two subpopulations (bimodal). The concentration of methanol in the same blood specimens ranged from 1 to 23 mg/l with a mean of 7.3 +/- 3.6 mg/l (+/- S.D.) and this distribution was markedly skew (+). The concentration of ethanol (x) and methanol (y) were positively correlated (r = 0.47, P less than 0.001) and implies that 22% (r2) of the variance in blood-methanol can be attributed to its linear regression on blood-ethanol. The regression equation was y = 3.6 + 2.1 x and the standard error estimate was 0.32 mg/l. This large scatter precludes making reliable estimates of blood-methanol concentration from measurements of blood-ethanol concentration and the regression equation. But higher blood-methanol concentrations are definitely associated with higher blood-ethanol in this sample of Swedish drinking drivers. Frequent exposure to methanol and its toxic products of metabolism, formaldehyde and formic acid, might constitute an additional health risk associated with heavy drinking in predisposed individuals. The determination of methanol in blood of drinking drivers in addition to ethanol could indicate long-standing ethanol intoxication and therefore potential problem drinkers or alcoholics. 相似文献
94.
Although the Great Depression has been the subject of much research, focus normally centers on the impact instead of the tactics developed by working-class organizations to tackle the problems it caused, specifically unemployment. Recent research has sought to fill this gap, but numerous areas remain uncovered. This paper covers two of these: the situation in Spain and the reaction of anarcho-syndicalist union – the Confederación Nacional de Trabajo. Spain presents an anomalous case; a country that saw the replacement of a semi-fascist dictatorship by a democracy in the 1930s. Furthermore, the fact that the initial government of the Spanish Second Republic included the Socialists provides an opportunity of comparing and contrasting the positions and policies of reformist and revolutionary workers’ organizations. The study is based on predominantly on articles appearing in the CNT newspaper Solidaridad Obrera. The conclusion reached is that for the CNT rising unemployment was a symptom of an irreversible trend in a failing capitalist system, which could only be solved by the revolutionary overthrow of that system. Nonetheless, the union had to present plausible solutions to ameliorate the conditions of the workers to attract the unemployed and thus, create a force strong enough to lead that revolutionary change. 相似文献
95.
96.
In this paper, I shall make the following propositions: in order to conceptually capture and represent the acts of political protest in a state of exception, we will need to reorient and supplement our representational apparatuses and also our theoretical frameworks for thinking about the gendered modes of protest under emergency laws and political abandonment. Through an analysis of the ‘naked protest’ of the Meira Peibis in Manipur, a ‘state of exception’ in democratic India, I shall argue that a series of supplementations to our current thinking on intersectionality, bare life and political subjectivation are required if we are to make sense of political acts of resistance, refusal and disavowal of the law of exception. 相似文献
97.
98.
99.
Although many iterations of the mammy in the last two centuries have received analytical attention, the construction of this figure as asexual or undesiring and undesirable remains to be interrogated. This essay attends to this under-theorised dimension of her image. Resisting a reading of the mammy as fixed in silence, I assert that she might instead ‘say nothing’, and bring into focus a black asexual agency that I call a declarative silence. This strategy of ‘saying nothing’ is then explored in a reading of the withholdings of the character of Mama in Gayl Jones’s neo-slave narrative, Corregidora (1975). 相似文献
100.