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701.
702.
With increasing regional disparities in economic development and living conditions in Europe, migration has become a key element in domestic politics of many European countries. One of the main concerns of analysis has been the search for important determinants of migration, however, the role of ?region specific cultural capital“ has not been considered. This omission is the starting point of our discussion and we introduce region specific capital as a form of cultural capital. In contrast to widespread approaches, hypotheses deriving from the theory of Pierre Bourdieu and his distinction of economic, social and cultural capital are deduced and empirically tested, using a representative survey of 3005 persons living in Saxony. The results show that the main determinants of migration are region specific cultural capital, dissatisfaction and age. 相似文献
703.
Dobberstein RC Huppertz J von Wurmb-Schwark N Ritz-Timme S 《Forensic science international》2008,179(2-3):181-191
Postmortem teeth are the most stable structures, and can be used to gain different information (age estimation, genetic data). Over long postmortem intervals (PMI), degradation processes may alter the molecular integrity and thus affect the reliability of applied molecular methods. Whereas some knowledge on the degradation of biomolecules in bone during the PMI exists, data for teeth are lacking. In particular, the impact of degradation processes in dentine on age estimation based on aspartic acid racemization (AAR) cannot be estimated yet. Hence, the molecular stability of both collagen and DNA was analyzed systematically, and their impact on the reliability of age estimation based on AAR and genetic analyses was checked. Two hundred and ten human and 59 porcine teeth were heated (90 degrees C in water) to simulate collagen and DNA diagenesis; 14 naturally aged teeth (PMI: 3 days to 1700 years) were analyzed comparatively. Peptide patterns of cyanogen bromide (CNBr)-cleaved collagen were employed as a new approach to check the collagen integrity. In the same samples, collagen yields, amino acid compositions, AAR in different protein fractions, and DNA integrity were analyzed. In heated human and porcine teeth the collagen content declined during the heating experiment. The amino acid composition in human samples was collagen-like until 12 days of heating. In naturally aged teeth, the collagen yielded from 9.5 to 15%, and no discrepancy of amino acid composition to that of modern collagen was observed. Electrophoresis of CNBr-peptides showed an altered pattern in experimentally degraded samples from day 10 on; naturally aged collagen displayed the typical collagen pattern. AAR increased in all protein fractions with increasing duration of the heating experiment; naturally aged samples displayed a slow accumulation of AAR. DNA degraded progressively, and after 32 h of heat exposure no more DNA was detectable, whereas the amplification of nuclear and mitochondrial DNA was successful up to 48 h. STR typing was reliable up to 16 h, and sex determination up to 40 h of heat exposure. In naturally aged samples of DNA quality, yield and typing success did not correlate with PMI. The data highlight a remarkable stability of collagen dental proteins. Within relevant forensic periods a postmortem rise of AAR under normal conditions is negligible, and analyses of dental DNA has a high chance to be successful. However, after large PMI and/or extreme postmortem conditions age estimation based on AAR and genetic analyses lose their reliability. 相似文献
704.
Immunohistochemical and molecularpathologic techniques have improved the diagnosis of myocarditis as compared with conventional histologic staining methods done according to the Dallas criteria. Additionally, immunohistochemistry and in situ-hybridization are able to demonstrate viral infection, e.g. cytomegaloviruses in salivary glands and lungs, locations both known to be involved in cytomegalovirusinfection. However, in many cases of proved cytomegalovirusinfection the cause of death remains unclear. We report on three children younger than 1-year of age, who died suddenly without prodromal symptoms. Their deaths were attributed to SIDS (sudden infant death syndrome). In situ-hybridization, immunohistochemical (LCA, CD45R0, CD68, MHC-class-II-molecules, E-selectine) and molecularpathologic investigations (PCR), however, suggested that death was caused by a cytomegalovirus-induced pneumonia or myocarditis. In the future, these methods should be used for investigating cases with suspicion of SIDS. 相似文献
705.
Nanotechnology has attracted significant research, funding, and policy activity in recent years in the US and many other countries.
Of particular interest are the locational characteristics of this emerging technology. This study examines the emergence of
nanotechnology in the US South to explore questions of regional standing and spatial trajectory, using an exploratory multi-indicator
approach. Our research employs an array of 10 indicators of knowledge generation, human capital, R&D funding, and patenting,
to uncover developments, clusters, and linkages in nanotechnology emergence. Results indicate that although there is nanotechnology
activity in every state in the US South, this activity agglomerates in a few locations. One emerging nanodistrict (North Carolina’s
Research Triangle) has prior strengths in high technology research and commercialization, especially based on biotechnology;
but other districts (e.g., Oak Ridge Tennessee and Atlanta, Georgia) that have strengths in certain aspects of the nanotechnology
research ecosystem have weaknesses in commercialization. The study illustrates how multi-indicator approaches can be developed
from existing databases, using customized search techniques, and how the insights from multi-indicator measurement can be
used to provide insights for research and innovation policy.
相似文献
Philip ShapiraEmail: |
706.
Abstract: Several applications of a microthermal desorption device for analysis of small forensic samples are presented. The method uses a solid phase microextraction holder with the fiber removed. In addition to samples of inks on paper, this device was successfully used for analysis of toners, various stains on bank notes, and lipstick stains on paper. Other small items encountered in a forensic science laboratory were also analyzed: particles of smokeless powder, particles of coffee, and automotive clear topcoat layer. The desorbed compounds were analyzed by gas chromatography with a flame ionization detector or by gas chromatography–mass spectrometry. This device can be used in connection with any kind of gas chromatograph. By selection of different injector temperatures, fractionated thermal desorption of samples is achieved. The procedure was demonstrated on samples of ballpoint pen ink of various age. 相似文献
707.
708.
Abstract. Many explanations of political involvement are based on the idea that higher levels of resources will be matched by higher levels of political involvement. Yet these kind of interpretations seem to overlook the fact that resources potentially increase individual autonomy and widen the scope of alternative actions, and so facilitate a decrease of political involvement. The analyses presented here are based on the rather paradoxical expectation that we will find a higher level of subjective political interest and, simultaneously, a lower level of political saliency among people commanding relatively high levels of social capital or other resources. The empirical evidence available for Western European countries in 1990 and 1998 essentially confirms the notion of diverging consequences of social capital (and other resources) for political involvement. People combining high political interest with a low saliency of politics are labelled spectators here. For them politics has lost its obligatory character – it is interesting and probably important to follow what goes on in this area, but compared with other matters its relevance is relatively low. Besides, a strong gender bias still can be found for each and every aspect of political involvement. 相似文献
709.
Michelle Wood Marleen Laloup Maria del Mar Ramirez Fernandez Kevin M. Jenkins Michael S. Young Jan G. Ramaekers Gert De Boeck Nele Samyn 《Forensic Science International Supplement Series》2005,150(2-3):227
We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC–MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept®, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC–MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2–200 μg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 μg/L. Limits of quantitation were estimated to be at 2 μg/L with limits of detection ranging from 0.2 to 0.5 μg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept® samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study. 相似文献
710.
Jan P. S. Fiselier 《Journal of Quantitative Criminology》1992,8(1):133-151
This paper tests the hypothesis of the stability of punishment as developed by Blumstein and his associates against Dutch prison data. After summarizing the existing empirical evidence, Dutch prison data are presented pertaining to the average daily population in penal institutions, on the one hand, and the number of admissions in these institutions, on the other hand. In three ways it is tested whether these data do support the hypothesis: regression analysis, Box-Jenkins analysis, and the analysis of a few dynamic models as presented by Berket al. (1981). The paper ends with discussing Blumstein's hypothesis and considers the way research into the extent of the prison population should be continued. 相似文献