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781.
782.
Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported. 相似文献
783.
784.
The purpose of this study was to combine morphoscopic and metric analyses to assess variation in nasal aperture size and shape of black and white South Africans. Thirteen landmarks were digitized from the bony nasal region of 152 crania using an electromechanic instrument for geometric morphometric (general procrustes analysis) and craniometric analyses. Elliptical Fourier analysis was used to assess shape of the nasal aperture via outlines applied through photographs. Both principal component and discriminant function analyses were applied to these statistical methods. Black South Africans were classified 95-96% correctly and white South Africans were classified 91-94% correctly. In a four-way analysis of sex and ancestry, classification accuracy ranged from 56 to 70%. Most misclassifications were between the sexes within each group which suggests an absence of sexual dimorphism. This study found that there is quantifiable variation in shape of the nasal aperture between black and white South African groups using all three statistical methods. In forensic application, standard craniometrics can be used to accurately classify an unknown person. 相似文献
785.
This study investigates the factors that shape the attitudes of scientists toward starting their own business or working in
a private sector firm. The analysis is based on data collected from scientists working in the German Max Planck Society, a
research institution devoted to basic science. We find that the scientists’ attractiveness of working in a private sector
firm or of starting their own business differ considerably according to their academic discipline and the self-reported commercial
potential of their research. The ability to take risks, prior work experience in private firms, and personal experience in
cooperating with industry lead to a positive attitude towards switching to private sector employment or entrepreneurship.
Strong willingness to freely distribute research findings is related to a low appeal of private sector work. 相似文献
786.
While a number of studies examine the parenting and social bond causes of low self-control in data obtained in the United States, very few focus on these constructs on data collected in international settings. The resulting gap in the literature is a major one in terms of the understanding of how low self-control potentially develops in other countries. This study tests several parenting and social bond models in an attempt to spur future global research on the concepts that are associated with low self-control. The data were collected from a convenience sample of 414 high school students in a suburb of a large Chinese city. Measures of Gottfredson and Hirschi’s parental variables as well as those of other investigators are included. Additionally, important social bonds such as maternal, school, and peer attachment are also specified. Results indicate that almost all of the parenting and bond measures are significantly associated with the development of low self-control. These findings indicate the possibility that both parenting and relationship factors are potentially important to the development of low self-control in Chinese high school students. 相似文献
787.
Why do imposed democracies endure and how do policy choices by imposing states affect durability? To study these questions, we formulate expectations linking durability to structural domestic conditions, the level of domestic security in the state into which a polity is imposed, the policies of imposing states, and the regional environment within which an imposed democracy is nested. We use event history to test our expectations on a sample of democracies imposed during the twentieth century. We find that relatively immutable, structural conditions, such as ethnic cleavages, economic development, and prior democratic experience strongly influence the durability of imposed democracies. While some policy choices made by imposing states can impact the survival of imposed democracy, they do so only modestly relative to the environment in which a democracy is imposed. 相似文献
788.
Michael Welner M.D. Emily E. Davey M.A. Adam Bernstein B.A. 《Journal of forensic sciences》2014,59(5):1254-1259
The fallibility of forensic science consultation is an ongoing and major justice concern. Prospective peer‐reviewed forensic consultation has over 10 years of application in American criminal and civil courts, adapting from the traditional oversight of teaching hospitals, rules of evidence and discovery, conventions of testimony of expert witnesses, and attorneys' overall trial strategy. In systematizing heightened oversight, this process ensures greater accountability in forensic science consultation. The integration of peer reviewers' complementary expertise and experience enhances the sophistication and overall quality of assessment. Forensic examination frequently involves the interface of different specialties. Multidisciplinary peer review augments expert proficiency with that of professional peers having different vantage points from relevant scientific disciplines. This approach ensures greater sophistication of a case inquiry, built‐in accountability, and streamlined processes when multiple experts are necessitated. Here, the authors present examples of several cases and the primary and secondary benefits of this collaborative, rigorous, cross‐disciplinary exercise. 相似文献
789.
Erin E. Waddell Ph.D. Jessica L. Frisch‐Daiello Ph.D. Mary R. Williams M.S. Michael E. Sigman Ph.D. 《Journal of forensic sciences》2014,59(5):1198-1204
Gas chromatography–mass spectrometry (GC–MS) data of ignitable liquids in the Ignitable Liquids Reference Collection (ILRC) database were processed to obtain 445 total ion spectra (TIS), that is, average mass spectra across the chromatographic profile. Hierarchical cluster analysis, an unsupervised learning technique, was applied to find features useful for classification of ignitable liquids. A combination of the correlation distance and average linkage was utilized for grouping ignitable liquids with similar chemical composition. This study evaluated whether hierarchical cluster analysis of the TIS would cluster together ignitable liquids of the same ASTM class assignment, as designated in the ILRC database. The ignitable liquids clustered based on their chemical composition, and the ignitable liquids within each cluster were predominantly from one ASTM E1618‐11 class. These results reinforce use of the TIS as a tool to aid in forensic fire debris analysis. 相似文献
790.
Matt DeLisi James O. Spruill Michael G. Vaughn Chad R. Trulson 《American Journal of Criminal Justice》2014,39(1):125-138
Gang membership is a robust correlate of homicide offending and victimization, but little is known about the association between gang status and various abnormal forms of homicide (e.g., multiple-victim homicide, sexual homicide, and abduction homicide). The current study utilized data from a large sample of 618 male convicted murderers to empirically examine gang status and diverse forms of homicide perpetration. Gang-involved offenders were nearly three times as likely to commit a normal homicide characterized as a single-victim murder. However, gang members were 64 % less likely to perpetrate multiple-victim murder. In other models, gang status reduced the likelihood of sexual homicide by 75 % and reduced the likelihood of abduction homicide by 56 %. These findings present an anomaly in the gang-homicide literature, and suggestions for additional research are offered. 相似文献