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701.
702.
Ludwig Niewoehner Ph.D. ; Jan Andrasko Ph.D. ; Jan Biegstraaten B.Sc. ; Lawrence Gunaratnam M.Sc. ; Sylvia Steffen Ph.D. ; Steffen Uhlig Ph.D. ; Sabine Antoni M.Sc. 《Journal of forensic sciences》2008,53(1):162-167
Abstract: Within the framework of the ENFSI Expert Working Group "Firearms" a proficiency test on the detection and identification of GSR by energy-dispersive scanning electron microanalysis (SEM/EDX) is carried out in a 2 years term. The latest test was performed in 2005/2006 and was denoted as GSR2005 . Seventy-five laboratories from 28 countries participated in this proficiency test and submitted in total 83 independent data-sets. The participating laboratories were requested to determine the total number of PbSbBa containing particles on a synthetic test sample following their own laboratory specific methods of automated GSR particle search and detection by SEM/EDX. Furthermore size and position of the detected particles had to be reported by the laboratories and were evaluated statistically. The results were compiled by means of z -scores according to the IUPAC and EURACHEM guidelines—assessing individual laboratory achievements (inter-laboratory) as well as intra-laboratory performance—and were compared to the results of the previous proficiency test run GSR2003 ( 1 ). The comparison shows that there is a noticeable improvement in the method's detection capability. 相似文献
703.
Jan Sundberg 《Scandinavian political studies》1999,22(3):221-241
The frozen party hypothesis has been rejected in several contemporary studies. However, by conceptualizing the Scandinavian parties in three categories, and by focusing the study on the three pole parties originally emphasized by Stein Rokkan, the bulk of the Scandinavian party system is still frozen. Diminishing class voting and electoral instability are inefficient measures of how well cleavages structures are reflected in the party system. Cleavages must be understood in a broader context where the struggle between the three fronts to incorporate new categories of voters is the very essence of an enduring cleavage structure. 相似文献
704.
European Journal of Political Research - 相似文献
705.
This study on trafficking in women from Central and Eastern Europe explores the contextual factors, the characteristics, and the motivation of victims as well as the methods of traffickers. A combination of rational choice theory, strain theory and social control theory forms the theoretical framework of our research. Based on information from experts in the field, interviews with victims, questionnaires, a study of dossiers and a search of the literature, we developed a typology of victims, which may be helpful for prevention and law enforcement. 相似文献
706.
707.
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
708.
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
709.
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
710.
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: |