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871.
Funded by the National Science Foundation and the National Nanotechnology Infrastructure Network (NNIN), this study asks qualitatively analyzes interviews with 48 nanoscientist users at four NNIN facilities. The main research questions were: (1) Do nanotechnologies pose unique social and ethical concerns?; (2) how are the risks associated with nanotechnology distributed among different human populations?; (3) what are specific policy steps that can be used to manage such risks? This study purposefully oversampled female scientists to correct for the historical underrepresentation of women in the nanotechnology workforce. By amplifying the voice of this science, technology, engineering, and mathematics (STEM) workforce minority, the policy discussion contained herein better reflects the concerns of the general population. The results, analyzed with the aid of qualitative data analysis software, yield interesting differences in risk characterization among the scientists and innovative policy suggestions for the nanoscience community and regulators alike.  相似文献   
872.
Many governments have implemented environmental justice mandates requiring agencies to consider the implications of cleanup decisions for poor and/or minority populations. To the extent that this mandate alters decisions, it usually does so by considering the composition of a community in the present without adjusting for potential demographic changes that may occur over time. However, communities change and these changes are likely to affect how well an agency meets its environmental justice mandate over the long term. In this research, an agent‐based model is introduced to simulate how alternative environmental remediation scenarios may affect environmental justice outcomes in a dynamic residential environment with two demographic classes with preferences for living in proximity to neighbors similar to themselves. Under these circumstances, there is unlikely to be one best strategy to achieve both environmental improvement and environmental equity, and a focus on valuable land is the least effective over the long run.  相似文献   
873.
Because of the unique character of the Hill‐Thomas hearings, journalists were left without a stock political plot to render the proceedings in familiar terms. Using narrative and rhetorical analyses, the study examines how newspaper journalists turned to so‐called women's entertainment genres such as soap opera and melodrama to dramatize and ultimately depoliticize the hearings. The study identifies four recurring rhetorical themes—melodrama, eroticization, agon, and privatization—that served to frame Hill's allegations of sexual harassment against Thomas not in terms of social and political debate but in terms of drama.  相似文献   
874.
This article presents the results of a validation study of a previously published method of sex determination from the temporal bone. The purpose of this study was to evaluate the lateral angle method for the internal acoustic canal for accurately determining the sex of human skeletal remains using measurements taken from computed tomography (CT) scans. Previous reports have observed that the lateral angle size in females is significantly larger than in males. The method was applied to an independent series of 77 postmortem CT scans (42 males, 35 females) to validate its accuracy and reliability. The mean lateral angle of the internal acoustic canal was found to be larger in females (46.5°) than in males (43.4°). However, the difference was not statistically significant and the sex differences reported in previous studies were not substantiated. In light of the observed results, the lateral angle method appears to be of minimal practical use in forensic anthropology and archeology.  相似文献   
875.
The use of an organic solvent to extract explosive residues from hand swabs and postblast debris inevitably leads to the coextraction of unwanted materials, usually in far greater quantities than any explosive residue. In this study, the extraction efficiency of a number of solvent cleanup procedures including solid‐phase extraction (SPE), adsorbent resins such as Chromosorb‐104, and traditional materials such as silica and Florisil was calculated using a quantitative liquid chromatography–ultraviolet (LC‐UV) detection procedure. The Oasis® HLB cartridge outperformed other cleanup procedures, with analyte recoveries approaching 95%, while the Amberlite XAD‐7 procedure returned the lowest overall recoveries. The matrix rejection ability of each method was then determined using a simulated highly contaminated matrix, with the adsorbent resins showing a higher degree of matrix rejection, which is seen as a reduction in background noise in the UV chromatogram using 210 nm detection.  相似文献   
876.
Fire investigation is a challenging area for the forensic investigator. The aim of this work was to use spectral changes to paint samples to estimate the temperatures to which a paint has been heated. Five paint samples (one clay paint, two car paints, one metallic paint, and one matt emulsion) have been fully characterized by a combination of attenuated total reflectance Fourier transform infrared (ATR‐IR), Raman, X‐ray fluorescence spectroscopy and powder X‐ray diffraction. The thermal decomposition of these paints has been investigated by means of ATR‐IR and thermal gravimetric analysis. Clear temperature markers are observed in the ATR‐IR spectra namely: loss of ν(C = O) band, >300°C; appearance of water bands on cooling, >500°C; alterations to ν(Si–O) bands due to dehydration of silicate clays, >700°C; diminution of ν(CO3) and δ(CO3) modes of CaCO3, >950°C. We suggest the possible use of portable ATR‐IR for nondestructive, in situ analysis of paints.  相似文献   
877.
Postmortem bacteriology can be a valuable tool for evaluating deaths due to bacterial infection or for researching the involvement of bacteria in various diseases. In this study, time‐dependent postmortem bacterial migration into liver, mesenteric lymph node, pericardial fluid, portal, and peripheral vein was analyzed in 33 autopsy cases by bacterial culturing and real‐time quantitative polymerase chain reaction (RT‐qPCR). None suffered or died from bacterial infection. According to culturing, pericardial fluid and liver were the most sterile samples up to 5 days postmortem. In these samples, multigrowth and staphylococci were not or rarely detected. RT‐qPCR was more sensitive and showed higher bacterial positivity in all samples. Relative amounts of intestinal bacterial DNA (bifidobacteria, bacteroides, enterobacter, clostridia) increased with time. Sterility of blood samples was low during the studied time periods (1–7 days). The best postmortem microbiological sampling sites were pericardial fluid and liver up to 5 days after death.  相似文献   
878.
Political sex scandals are largely absent in some democracies but proliferate in others. However, there have so far been few if any comprehensive attempts to document the actual number of sex scandals that have occurred and to explain their presence (and, indeed, absence), and the one study that has (Barker's 1994 study) ended in the early 1990s and had numerous problems in relation to defining and documenting such scandals. Based on extensive research, this article documents the number of sex scandals in eight advanced industrial democracies and tries to explain their occurrence using Charles Ragin's fuzzy set qualitative comparative analysis. The article has three goals: to determine the number of sex scandals in different democracies, explain why this might be, and demonstrate the utility of fuzzy set qualitative case analysis for small- and medium-N comparative research.  相似文献   
879.
Weight is often one of the few recoverable data when analyzing human cremains but references are still rare, especially for European populations. Mean weights for skeletal remains were thus documented for Portuguese modern cremations of both recently deceased individuals and dry skeletons, and the effect of age, sex, and the intensity of combustion was investigated using both multivariate and univariate statistics. The cremains from fresh cadavers were significantly heavier than the ones from dry skeletons regardless of sex and age cohort (p < 0.001 to p = 0.003). As expected, males were heavier than females and age had a powerful effect in female skeletal weight. The effect of the intensity of combustion in cremains weight was unclear. These weight references may, in some cases, help estimating the minimum number of individuals, the completeness of the skeletal assemblage, and the sex of an unknown individual.  相似文献   
880.
It is well known that temperature significantly affects corpse decomposition. Yet relatively few taphonomy studies investigate the effects of seasonality on decomposition. Here, we propose the use of the Köppen‐Geiger climate classification system and describe the decomposition of swine (Sus scrofa domesticus) carcasses during the summer and winter near Lincoln, Nebraska, USA. Decomposition was scored, and gravesoil chemistry (total carbon, total nitrogen, ninhydrin‐reactive nitrogen, ammonium, nitrate, and soil pH) was assessed. Gross carcass decomposition in summer was three to seven times greater than in winter. Initial significant changes in gravesoil chemistry occurred following approximately 320 accumulated degree days, regardless of season. Furthermore, significant (p < 0.05) correlations were observed between ammonium and pH (positive correlation) and between nitrate and pH (negative correlation). We hope that future decomposition studies employ the Köppen‐Geiger climate classification system to understand the seasonality of corpse decomposition, to validate taphonomic methods, and to facilitate cross‐climate comparisons of carcass decomposition.  相似文献   
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