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981.
982.
983.
984.
There are a number of forensic cases in which the identification of the epithelial cell type from which DNA originated would provide important probative evidence. This study aimed to develop a technique using histological staining of fixed cells to distinguish between skin, buccal and vaginal epithelium. First, 11 different stains were screened on formalin-fixed, wax-embedded cells from five women. Samples were analysed qualitatively by examining staining patterns (colour) and morphology (absence or presence of nuclei). Three of the staining methods – Dane's, Csaba's and Ayoub-Shklar – were successful in distinguishing skin epithelial cells from buccal and vaginal. Second, cells were smeared directly onto slides, fixed with one of five fixatives and stained with one of the three stains mentioned above. Methanol fixation, coupled with the Dane's staining method, specific to keratin, was the only technique that distinguished between all three cell types. Skin cells stained magenta, red and orange and lacked nuclei; buccal cells stained predominantly orange–pink with red nuclei; while vaginal cells stained bright orange with orange nuclei and a blue extracellular hue. This staining pattern in vaginal cells was consistent in samples collected from 50 women aged between 18 and 67. Identification of cell type from unlabelled micrographs by 10 trained observers showed a mean success rate of 95%. The results of this study demonstrate that histological staining may provide forensic scientists with a technique for distinguishing between skin, buccal and vaginal epithelial cells and thus would enable more conclusive analyses when investigating sexual assault cases.  相似文献   
985.
No consensus yet exists on how to handle incidental findings (IFs) in human subjects research. Yet empirical studies document IFs in a wide range of research studies, where IFs are findings beyond the aims of the study that are of potential health or reproductive importance to the individual research participant. This paper reports recommendations of a two-year project group funded by NIH to study how to manage IFs in genetic and genomic research, as well as imaging research. We conclude that researchers have an obligation to address the possibility of discovering IFs in their protocol and communications with the IRB, and in their consent forms and communications with research participants. Researchers should establish a pathway for handling IFs and communicate that to the IRB and research participants. We recommend a pathway and categorize IFs into those that must be disclosed to research participants, those that may be disclosed, and those that should not be disclosed.  相似文献   
986.
Most of the empirical literature on gender and policing has assessed gender differences in arrest levels and police use of force. While simple gender differences in police behavior are important for understanding skills men and women bring to the policing occupation, research must also determine under what conditions gender differences emerge and what factors impact the relationship between officer gender and behavior for this knowledge to be constructive. Although sexy, arrest and force decisions occur when police discretion is often limited, adding little to the knowledge of how gender affects everyday police-citizen encounters. Using data from systematic social observations of police-citizen encounters in St. Petersburg, Florida and Indianapolis, Indiana, this article replicates past analyses of gender differences in police utilization of controlling and supporting behaviors, but also extends the analyses by assessing the possible impact of intervening situational and organizational characteristics, determining under what conditions female officers utilize different behaviors from their male counterparts. The findings provide mixed support for the general hypothesis of gender-specific responses. Consistent with previous literature, this research suggests that women are much less likely than men to utilize extreme controlling behavior, such as threats, physical restraint, search, and arrest. Surprisingly, the findings do not confirm that women are more likely than men to use supporting behaviors, even when controlling for women's greater likelihood to hold community policing assignments. These findings, while unexpected, are important. Simply assuming female officers manifest stereotypically feminine traits in policing tasks is clearly an overly simplistic conceptualization of the meaning and impact of gender in policing. The implications for female officers, policing, and future research are discussed.  相似文献   
987.
This article intends to unveil some of the main theoretical backgrounds and current tendencies of environmental sociology in Brazil. But we are mainly interested in providing a historical reconstruction of the societal internalization of environmental concerns in Brazil, on both state and civic levels, with an emphasis on the transformations that took place over the 1970–1990s period. We argue that environmental civil associations do not find either a legal idiom or public forums by means of which they could turn their demands and moral concerns into a binding juridical code. This is so because, on the one hand, their moral concerns, even when based on de-traditionalized and abstract principles, are not paralleled with an autonomous legal framework, strong enough to set limits to the functioning of both the political-administrative apparatus as well as to economic actors. As we contend, this helps to explain why the environmental legislation in Brazil is rhetorically manipulated on a regular basis—and, hence, set aside whenever it contradicts other priorities. On the other hand, environmental concerns have always met with difficulties to become a priority in the Brazilian polity. Ultimately, our main goal is to carry out a critical consideration of the theoretical links that are widely set in the field of sociological theory between environmental concerns and modernity.  相似文献   
988.
Abstract: The primary purpose of this article is to investigate the factors that predict the efficiency of residential recycling collection services in Canadian local governments. The findings are based on a survey of 128 residential recycling producers from all regions of Canada. One of the most significant findings is the lack of a relationship between private‐sector companies collecting recyclables and the overall efficiency of collection operations. The dominance of the private‐sector collection of recyclables (over seventy‐seven per cent of all producers were contracted companies) does not translate into greater efficiencies. The most important variables in the model are amenable to local control. They include tonnes collected per vehicle per year, requiring full bins, inclusion of composting operations in the overall recycling program, the number of different kinds of materials recycled, participation rate, and reliance on side‐loading collection vehicles. Among the direct predictors of unit costs, the key underlying factor is the productivity of residential recycling operations. Because recyclables are marketed, handling them takes time, reduces the weights that collection vehicles can carry, and generally reduces productivity. Even diligent efforts to improve productivity will not bring recycling costs down to the levels for residential solid‐waste collection. Sommaire: L'objectif principal du présent article est d'examiner les facteurs qui prévoient l'efficacité des services de collecte de produits recyclables résidentiels dans les municipalités canadiennes. Les résultats reposent sur un sondage réalisé auprès de 128 producteurs de collecte de produits recyclables résidentiels opérant dans toutes les régions du Canada. L'un des résultats les plus notoires est le manque de relations entre les sociétés du secteur privé qui récupèrent les produits recyclables et l'efficacité d'ensemble des opérations de collecte. La prédominance de la collecte de produits recyclables par le secteur privé (plus de soixante‐dix‐sept pour cent de tous les producteurs étaient des sociétés contractuelles) ne se traduit pas par une plus grande efficacité. Les variables les plus importantes du modèle peuvent faire l'objet d'un contrôle local. Elles comprennent les tonnes récupérées par véhicule par an, l'exigence de poubelles pleines, l'inclusion d'opérations de compostage au programme général de recyclage, le nombre de différentes sortes de matériaux recyclés, le taux de participation, et le recours à des camions de collecte à chargement latéral. Parmi les variables explicatives directes des coûts unitaires, le principal facteur sous‐jacent est la productivité des opérations de recyclage résidentiel. Comme les produits recyclables sont commercialisés, leur manutention prend du temps, réduit le poids que les camions de collecte peuvent transporter, et réduit d'une manière générale la productivité. Même des efforts diligents pour améliorer la productivité ne feront pas baisser les coûts du recyclage aux niveaux de ceux de la collecte des déchets solides résidentiels.  相似文献   
989.
990.
Two cases of allelic loss at the D19S433 locus after multiplex PCR with the AmpFlSTR Identifiler kit (Applied Biosystems) are described. In both cases the failure of PCR resulted in genetic inconsistencies due to opposite homozygosity. After singleplex PCR with published primers additional alleles were observed and Mendelian inheritance was restored. These PCR products were sequenced and in both cases the same 4 bp deletion near the 3′ end of the repeat region was detected in two alleles of different length. The frequency of these null alleles (two events in 1026 allelic transfers) amounts to 0.0019 (95% confidence limits: 0.0002-0.0070).  相似文献   
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