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41.
Now that racism has been officially recognized in Brazil, and some universities have adopted affirmative-action admission policies, measures of the magnitude of racial inequality and analyses that identify the factors associated with changes in racial disparities over time assume particular relevance to the conduct of public debate. This study uses census data from 1950 to 2000 to estimate the probability of death in the early years of life, a robust indicator of the standard of living among the white and Afro-Brazilian populations. Associated estimates of the average number of years of life expectancy at birth show that the 6.6-year advantage that the white population enjoyed in the 1950s remained virtually unchanged throughout the second half of the twentieth century, despite the significant improvements that accrued to both racial groups. The application of multivariate techniques to samples selected from the 1960, 1980, and 2000 census enumerations further shows that, controlling for key determinants of child survival, the white mortality advantage persisted and even increased somewhat in 2000. The article discusses evidence of continued racial inequality during an era of deep transformation in social structure, with reference to the challenges of skin color classification in a multiracial society and the evolution of debates about color, class, and discrimination in Brazil.  相似文献   
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The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.  相似文献   
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Aerobic sport performance may be strongly influenced by the number of red blood cells available for transport and delivery of oxygen from lungs to muscles. Often, athletes search for an acute increase in red blood cells by means of blood transfusions. This paper reviews the possibilities for detecting such prohibited practice. Flow cytometry methods are able to detect a double population of red blood cell membrane surface antigens, thus revealing an allogeneic transfusion. Other ingenious approaches for total hemoglobin mass measurements or to test for the metabolites of blood bag plasticizers in urine are new trends for facing the detection of autologous transfusions. Steady increase of red blood cell number may be obtained also by erythropoietic stimulant agents such as erythropoietin, analogs and mimetics. The challenge of detecting those substances has stimulated the development of indirect markers of altered erythropoiesis, leading to the consequent development of the hematological blood passport approach, which is gaining legal acceptance.  相似文献   
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Even though trace evidence is becoming more and more important in legal cases, only little is known about the influence of task and context factors on comparative judgments. In the present study we investigated how expectations and complexity affect shoe print examinations and to what extent differences exist between beginners and experienced examiners. Twelve examiners assessed similarity between a shoe print and a shoe for eight different cases. For half the cases expectation was induced by providing additional incriminating evidence. A complex case meant that the print was relatively noisy, for example because the perpetrator rotated his foot. A simple case meant that the print was clear. The results showed that there was no effect of expectation and no effect of experience. Only complexity affected the examiners' assessments: when the background was noisy, the acquired features received a lower evidential value than when the background was clear. Apparently, examiners compensated for the quality of the print and were more cautious in drawing conclusions when prints were less clear. Even though the results allow for some optimism with regard to the influence of expectations on shoe print examinations, it has to be taken into account that the Dutch procedure is supported by a formal guideline, which may (partly) explain the present findings.  相似文献   
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ABSTRACT: The incidence of rape has increased, especially in metropolitan areas, such as the city of São Paulo. In Brazil, studies about it have shown that the majority of this type of crime is committed by the relatives and persons close to the victim. This has made the crime more difficult to be denounced, as only 10% of the cases are reported to competent police authorities. Usually, cytological exams are carried out in sex crime investigations. The difficulty in showing the presence of spermatozoa is frequent, but it does not exclude the presence of male DNA. The absence of spermatozoa in material collected from rape victims can be due to several factors, including the fact that the agressor suffers from azoospermia. This condition can be the result of a successful vasectomy. As the majority of DNA in the ejaculation sample is from spermatozoa, there is much less DNA to be analyzed. This study presents the application of Y‐STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) in DNA analysis of sperm samples from 105 vasectomized men. The study demonstrated a great variation in DNA concentration. DNA extraction and amplification was possible in all sperm samples even in the absence of spermatozoa. The same profile was observed, for each individual, from DNA extracted from blood, pre‐ and postvasectomy semen samples. The use of markers specific for Y chromosome in sex crime cases, especially in the absence of spermatozoa, is very important, mainly because in most situations there is a small quantity of the agressor's DNA in the medium and a large quantity of the victim's DNA.  相似文献   
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Book reviews     
Deane Curtin, Chinnagounders’ Challenge: The Question of Ecological Citizenship. Bloomington: Indiana University Press, 1999.

Jim Yong Kim, et ah, ed., Dying For Growth: Global Inequality and the Health of the Poor. Monroe, ME: Common Courage Press, 2000.

Lester R. Brown, Christopher Flavin, Hilary French, et al., eds., State of the World 1998. New York: W.W. Norton and Company, 1998.

Margit Mayer and John Ely, eds., The German Greens. Paradox Between Movement and Party. Translated by Michael Schatzschneider. Philadelphia: Temple University Press, 1998.  相似文献   
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Technology Trade     
This study addresses the question of why some countries import more research and development-intensive goods than others. Using a panel data set of 80 countries for the period 1970–1995, results indicate that domestic investment, foreign direct investment and the quality of intellectual property rights systems positively affect technology imports. However, the higher the percentage of the workforce with primary studies, the lower technology imports are. Moreover, intellectual property rights tend to reinforce the positive role played by foreign direct investments in importing technology while the ability of imitation reduces the effect of intellectual property rights.  相似文献   
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