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31.
Extreme fragmentation can complicate the inventory of human skeletal remains. In such cases, skeletal mass can provide information regarding skeleton completeness and the minimum number of individuals. For that purpose, several references for skeletal mass can be used to establish comparisons and draw inferences regarding those parameters. However, little is known about the feasibility of establishing comparisons between inherently different materials, as is the case of curated reference skeletal collections and human remains recovered from forensic and archaeological settings. The objective of this paper was to investigate the effect of inhumation, weather and heat exposure on the skeletal mass of two different bone types. This was investigated on a sample of 30 human bone fragments (14 trabecular bones and 16 compact bones) that was experimentally buried for two years after being submitted to one of four different heat treatments (left unburned; 500?°C; 900?°C; 1000?°C). Bones were exhumed periodically to assess time-related mass variation. Skeletal mass varied substantially, decreasing and increasing in accordance to the interchanging dry and wet seasons. However, trends were not the same for the two bone types and the four temperature thresholds. The reason for this appears to be related to water absorption and to the differential heat-induced changes in bone microporosity, volume, and composition. Our results suggest that mass comparisons against published references should be performed only after the skeletal remains have been preemptively dried from exogenous water.  相似文献   
32.
Juvenile age estimation methods used in forensic anthropology generally lack methodological consistency and/or statistical validity. Considering this, a standard approach using nonparametric Multivariate Adaptive Regression Splines (MARS) models were tested to predict age from iliac biometric variables of male and female juveniles from Marseilles, France, aged 0–12 years. Models using unidimensional (length and width) and bidimensional iliac data (module and surface) were constructed on a training sample of 176 individuals and validated on an independent test sample of 68 individuals. Results show that MARS prediction models using iliac width, module and area give overall better and statistically valid age estimates. These models integrate punctual nonlinearities of the relationship between age and osteometric variables. By constructing valid prediction intervals whose size increases with age, MARS models take into account the normal increase of individual variability. MARS models can qualify as a practical and standardized approach for juvenile age estimation.  相似文献   
33.
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   
34.
Developing a strategy to characterize the odor prints of individuals should be relevant to support identification obtained using dogs in courts of justice. This article proposes an overview of the techniques used for the forensic profiling of human odor. After reviewing the origin of human odor—both genetic and physiological—the different analytical steps from sample collection to statistical data processing are presented. The first challenge is the collection of odor, whether by direct sampling with polymer patches, cotton gauze, etc., or indirect sampling with devices like Scent Transfer Unit. Then, analytical techniques are presented. Analyses are commonly performed with gas chromatography coupled with mass spectrometry. As they yield large amounts of data, advanced statistical tools are needed to provide efficient and reliable data processing, which is essential to give more probative value to information.  相似文献   
35.
Marketing is a relatively new academic discipline. Arts marketing as a subfield of marketing began in the 1960s. Sociologists and economists were the first to contribute to the knowledge. American authors then stepped in the late 1970s to the 1990s. Starting in the 2000s, European as well as Australian colleagues took the lead in terms of number of articles published. Currently, academic research by marketing scholars is enriching this new field of inquiry on consumer behaviors and on the four traditional P's of marketing: product (and brand), price, place, and promotion.  相似文献   
36.
Individuals experiencing non-suicidal self-injurious (NSSI) thoughts only are greatly overlooked by current research. This investigation aimed at determining how three groups of university students differed in their reported quality of childhood relationships with parents, and histories of physical and sexual abuses. These groups included students experiencing only NSSI thoughts (n = 126), students engaging in NSSI actions (n = 90), and students exhibiting neither (n = 1,080). Results showed that individuals experiencing NSSI thoughts only, and those engaging in NSSI actions reported poorer relationships with parents and more physical abuse than the No NSSI group; however, NSSI thoughts and NSSI action groups had similar outcomes to one another for most variables. These findings suggest that individuals experiencing only NSSI thoughts share similar negative childhood environments associated with engagement in NSSI action and that they should be included in future research, particularly investigations aimed at identifying protective factors that could prevent them from engaging in NSSI.  相似文献   
37.
38.
This article addresses the relationship between institutionalized citizen participation at the municipal level and clientelism. It argues, contrary to what the literature has suggested, that the institutionalization of local citizen participation does not necessarily lead to the erosion of clientelism. Drawing on a comparative case study of participatory experiences in two Mexican municipalities, León and Nezahualcóyotl, this study argues that participation does matter, but that not all types of participation have the same effect on state‐society relations. Institutional design is important in assessing the significance of popular participation in defining the relationship between the state and its citizens, but informal practices are even more important determinants of citizens' level of autonomy in institutionalized participatory mechanisms. This level of autonomy, in turn, determines the potential for such local institutions to become a means to overcome clientelism as the mechanism traditionally characterizing state‐society relationships in Mexico.  相似文献   
39.
A fully validated, sensitive and specific method for the extraction and quantification of Delta(9)-tetrahydrocannabinol (THC) and 11-nor-9-carboxy-Delta(9)-THC (THC-COOH) and for the detection of 11-hydroxy-Delta(9)-THC (11-OH THC) in oral fluid, urine and whole blood is presented. Solid-phase extraction and liquid chromatography-mass spectrometry (LC-MS) technique were used, with electrospray ionization. Three ions were monitored for THC and THC-COOH and two for 11-OH THC. The compounds were quantified by selected ion recording of m/z 315.31, 329.18 and 343.16 for THC, 11-OH THC and THC-COOH, respectively, and m/z 318.27 and 346.26 for the deuterated internal standards, THC-d(3) and THC-COOH-d(3), respectively. The method proved to be precise for THC and THC-COOH both in terms of intra-day and inter-day analysis, with intra-day coefficients of variation (CV) less than 6.3, 6.6 and 6.5% for THC in saliva, urine and blood, respectively, and 6.8 and 7.7% for THC-COOH in urine and blood, respectively. Day-to-day CVs were less than 3.5, 4.9 and 11.3% for THC in saliva, urine and blood, respectively, and 6.2 and 6.4% for THC-COOH in urine and blood, respectively. Limits of detection (LOD) were 2 ng/mL for THC in oral fluid and 0.5 ng/mL for THC and THC-COOH and 20 ng/mL for 11-OH THC, in urine and blood. Calibration curves showed a linear relationship for THC and THC-COOH in all samples (r(2)>0.999) within the range investigated. The procedure presented here has high specificity, selectivity and sensitivity. It can be regarded as an alternative method to GC-MS for the confirmation of positive immunoassay test results, and can be used as a suitable analytical tool for the quantification of THC and THC-COOH in oral fluid, urine and/or blood samples.  相似文献   
40.
The polymorphism of 15 STR loci has been studied in a population sample of 193 healthy unrelated individuals from the population of Duzce, a city in the northwestern Turkey. The most valuable loci, from forensic point of view according to their power of discrimination values, were D2S1338, D18S51, FGA, and D19S433 where CSF1PO appeared to be the least powerful one. From paternity point of view, FGA, D21S11 were found to be the loci with highest exclusion value whereas D3S1358 and TPOX were the locus with the lowest exclusion.  相似文献   
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