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171.
Does the uncertainty associated with post-authoritarian transitions cause political and social polarization? Does ubiquitous social media exacerbate these problems and thus make successful democratic transitions less likely? This article examines these questions in the case of Egypt between the 11 February 2011 fall of President Hosni Mubarak and the 3 July 2013 military coup, which overthrew President Mohamed el-Morsi. The analysis is based on a Twitter dataset including 62 million tweets by 7 million unique users. Using a mix of quantitative and qualitative methods, we demonstrate how clusters of users form and evolve over time, the density of interactions between them, and the flow of particular types of information through the clustered network structure. We show that the Egyptian Twitter public developed into increasingly isolated clusters of the like-minded which shared information unevenly. We argue that the growing distance between these clusters encouraged political conflict and facilitated the spread of fear and hatred, which ultimately undermined the democratic transition and won popular support for the military coup.  相似文献   
172.
173.
The authors trace the successive transformations of the large London commercial law firm, which entered the 20th century as a small group of partners, typically from one or more family groups, surrounded by a large group of working class clerks who performed much of the ‘professional work’. After mid-century this firm based on kinship and class hierarchy gave way to a larger firm consisting of non-kin partners selected meritocratically presiding over an increasing band of assistant solicitors and trainees recruited on the basis of their educational credentials and taking part in a promotion-to-partnership tournament. In the last decade of the century, the central institutions and understandings of this meritocratic firm gave way to a constellation of larger, less stable, and increasingly supra-national aggregations, in a setting pervaded by a fascination, both instrumental and narcissistic, with rank and image.  相似文献   
174.
Reliability and validity are critical standards of scientific inquiry. This analysis directs attention to problems of reliability in data collection and to problems of validity in measuring two key criminal justice variables: the offense and the sentence. The discussion and empirical analysis indicate that reliability of official information sources in criminal justice cannot be assumed. Furthermore, there is evidence to suggest that the criterion of validity is even more elusive. This elusiveness is demonstrated in the operational definition of criminal offense, an important predictor variable, and in attemps to operationally define the criminal sanction, i.e., the disposition of charges against convicted defendants. These considerations suggest that research in the sentencing area may not be directed to the subject at hand and that research results should be interpreted with “scientific” caution.  相似文献   
175.
In forensic medicine, specialists might face difficulties when estimating age at death from fetal remains. Depending on the state of preservation, this age assessment is essentially based on the diaphyseal size of long bones. In a previous work, for the measurement of fetal femoral ossified shafts, we already established a simple and reliable method using a radiographic protocol. Since we previously stated that radiographic measurement values were closer to real anatomical size than ultrasonographic ones, in the present study we decided to check the importance of the difference between radiographic and anatomical measurements. Therefore, we dissected 30 pairs of fetal femurs and compared the difference between the two kinds of measurements (in percentages). This difference seemed to be slight (4.027%), but it was large enough to entail significant differences (p < 0.001). In order to provide a correction factor for radiographic measurements, we established a linear regression formula, which was tested on another sample of 30 pairs of dissected femurs. As a consequence of the good results, we improved the linear regression using a powerful statistical tool: the bootstrap. Finally, we obtained a simple equation that allowed us to figure out the real anatomical size with an R2 of 99% and a mean relative difference of 0.153% (with a standard error of 0.252 mm, and therefore a 95% confidence interval with limits of -0.35 and 0.657 mm). This difference did not entail any significant differences (p = 0.498), and therefore, we concluded that with the proposed correction, radiographic measurements can easily be used by forensic specialists in their daily tasks or to establish new growth standards in order to best fit their population of interest.  相似文献   
176.
Analytical records concerning 440 living drivers suspected of driving under the influence of drug (DUID) were collected and examined during a 2 years period ranging from 2002 to 2003 in canton de Vaud, Valais, Jura and Fribourg (Switzerland). This study included 400 men (91%) and 40 women (9%). The average age of the drivers was 28+/-10 years (minimum 16 and maximum 81). One or more psychoactive drugs were found in 89% of blood samples. Half of cases (223 of 440, 50.7%) involved consumption of mixtures (from 2 to 6) of psychoactive drugs. The most commonly detected drugs in whole blood were cannabinoids (59%), ethanol (46%), benzodiazepines (13%), cocaine (13%), amphetamines (9%), opiates (9%) and methadone (7%). Among these 440 cases, 11-carboxy-THC (THCCOOH) was found in 59% (median 25 ng/ml (1-215 ng/ml)), Delta(9)-tetrahydrocannabinol (THC) in 53% (median 3 ng/ml (1-35 ng/ml)), ethanol in 46% (median 1.19 g/kg (0.14-2.95 g/kg)), benzoylecgonine in 13% (median 250 ng/ml (29-2430 ng/ml)), free morphine in 7% (median 10 ng/ml (1-111 ng/ml)), methadone in 7% (median 110 ng/ml (27-850 ng/ml)), 3,4-methylenedioxymethamphetamine (MDMA) in 6% (median 218 ng/ml (10-2480 ng/ml)), nordiazepam in 5% (median 305 ng/ml (30-1560 ng/ml)), free codeine in 5% (median 5 ng/ml (1-13 ng/ml)), midazolam in 5% (median 44 ng/ml (20-250 ng/ml)), cocaine in 5% (median 50 ng/ml (15-560 ng/ml)), amphetamine in 4% (median 54 ng/ml (10-183 ng/ml)), diazepam in 2% (median 200 ng/ml (80-630 ng/ml)) and oxazepam in 2% (median 230 ng/ml (165-3830 ng/ml)). Other drugs, such as lorazepam, zolpidem, mirtazapine, methaqualone, were found in less than 1% of the cases.  相似文献   
177.
Players are assumed to rank each other as coalition partners. Two processes of coalition formation are defined and illustrated:
  • Fallback (FB): Players seek coalition partners by descending lower and lower in their preference rankings until some majority coalition, all of whose members consider each other mutually acceptable, forms.
  • Build-up (BU): Same descent as FB, except only majorities whose members rank each other highest form coalitions.
BU coalitions are stable in the sense that no member would prefer to be in another coalition, whereas FB coalitions, whose members need not rank each other highest, may not be stable. BU coalitions are bimodally distributed in a random society, with peaks around simple majority and unanimity; the distributions of majorities in the US Supreme Court and in the US House of Representatives follow this pattern. The dynamics of real-life coalition-formation processes are illustrated by two Supreme Court cases.
  相似文献   
178.
Conceptual Analysis and Measurement of Adolescent Autonomy   总被引:6,自引:0,他引:6  
The aim of the present study was to examine the concept of adolescent autonomy. A conceptual analysis of different theoretical perspectives has resulted in an integrative model of attitudinal, emotional, and functional autonomy. Attitudinal autonomy refers to the cognitive process of choosing and defining a goal. Emotional autonomy refers to the affective process of feeling confident about one's own choices and goals. Functional autonomy refers to the regulatory process of developing a strategy to achieve these goals. The empirical value of this model was tested by developing a questionnaire assessing adolescent autonomy. Subjects were 400 adolescents between 12 and 18 years old. Confirmatory factor analyses (LISREL 8) provided evidence for the 3 hypothesized dimensions.  相似文献   
179.
Gas chromatography was used to study the cannabinoid content ("potency") of illicit cannabis seized by police in England in 2004/5. Of the four hundred and fifty two samples, indoor-grown unpollinated female cannabis ("sinsemilla") was the most frequent form, followed by resin (hashish) and imported outdoor-grown herbal cannabis (marijuana). The content of the psychoactive cannabinoid delta 9-tetrahydrocannabinol (THC) varied widely. The median THC content of herbal cannabis and resin was 2.1% and 3.5%, respectively. The median 13.9% THC content of sinsemilla was significantly higher than that recorded in the UK in 1996/8. In sinsemilla and imported herbal cannabis, the content of the antipsychotic cannabinoid cannabidiol (CBD) was extremely low. In resin, however, the average CBD content exceeded that of THC, and the relative proportions of the two cannabinoids varied widely between samples. The increases in average THC content and relative popularity of sinsemilla cannabis, combined with the absence of the anti-psychotic cannabinoid CBD, suggest that the current trends in cannabis use pose an increasing risk to those users susceptible to the harmful psychological effects associated with high doses of THC.  相似文献   
180.
Headspace solid-phase microextraction (HS-SPME) is assessed as an alternative to liquid-liquid extraction (LLE) currently used for 3,4-methylenedioxymethampethamine (MDMA) profiling. Both methods were compared evaluating their performance in discriminating and classifying samples. For this purpose 62 different seizures were analysed using both extraction techniques followed by gas chromatography-mass spectroscopy (GC-MS). A previously validated method provided data for HS-SPME, whereas LLE data were collected applying a harmonized methodology developed and used in the European project CHAMP. After suitable pre-treatment, similarities between sample pairs were studied using the Pearson correlation. Both methods enable to distinguish between samples coming from the same pre-tabletting batches and samples coming from different pre-tabletting batches. This finding emphasizes the use of HS-SPME as an effective alternative to LLE, with additional advantages such as sample preparation and a solvent-free process.  相似文献   
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