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61.
The author reports on a study of the liquid nitrogen treatment of warts at the Rutgers University Student Health Center. He demonstrates that liquid nitrogen therapy is a safe, effective treatment method, appropriate for use by nurses and other primary providers in a college health setting.  相似文献   
62.
Unions,PAC contributions,and the NAFTA vote   总被引:1,自引:0,他引:1  
Political action committees (PACs), especially those controlled by organized labor and business, have been shown to affect Congressional voting. We explore how PACs influenced the House of Representatives’ vote on the North American Free Trade Agreement (NAFTA). The NAFTA vote is analyzed because organized labor strongly opposed the treaty while business generally supported it and because of the straight-forward voting generated by its fast-track status. Probit analysis of a unique, unpublished data set containing information about PAC and non-PAC contributions to the 1992 House election campaigns demonstrates that Representatives who depended largely on labor PACs tended to oppose NAFTA, while Representatives who derived a large proportion of their campaign contributions from business PACs tended to favor its passage.  相似文献   
63.
Modeling for Risk Assessment of Neurotoxic Effects   总被引:2,自引:0,他引:2  
The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels.  相似文献   
64.
65.
This study explored how students choose careers, their attitudes toward vocational education, and whether or not they would consider enrolling in a nontraditional vocational education program.  相似文献   
66.
67.
The possibility that carbon dioxide emissions from fossil fuel use might lead to global warming has become a leading environmental concern. Many scientific and environmental organizations have called for immediate action to limit carbon dioxide production. For the most part, however, public debate has focused on a single policy instrument: a carbon tax applied to fossil fuels in proportion to their carbon content. We present a detailed model of the U.S. economy and use it to compare carbon taxes with two other instruments that could achieve the same reduction in carbon dioxide emissions: a tax on the energy content of fossil fuels (a BTU tax) and an ad valorem tax on fuel use. We find that carbon taxes can achieve a given reduction with the least overall effect on the economy, but with a large effect on coal mining. Energy taxes are fairly similar to carbon taxes but have slightly less impact on coal mining and slightly greater overall cost. In contrast, ad valorem taxes fall much more lightly on coal mining but have a much greater effect on the economy as a whole.  相似文献   
68.
Arising as a powerful challenge to programmatic views of sociology that sought to determine stable laws underpinning social order, ethnomethodology set out an alternative programme to reveal social order as a dynamic, contingent ‘ongoing accomplishment’. This programme was neither micro nor macro, but was concerned with different contexts of accountability in which both individuals and institutions are given identity and reproduced. Recognising everyday life as an achievement, collective sense making, and the central importance of talk as a social process, ethnomethodology had an impact on all those arenas of sociology where ordinary interaction is an element. This introduction to the special section discusses the contributions of each of the papers – which cover mundane reasoning, social learning, the early acquisition of social competence, and the application of membership categorization analysis to gender – in relation to the continuing relevance of Garfinkel's legacy to contemporary sociological theory and practice.  相似文献   
69.
This article is concerned with the determinants of English language proficiency among immigrants in a longitudinal survey for Australia. It focuses on both visa category and variables derived from an economic model of the determinants of destination‐language proficiency among immigrants. Skills‐tested and economic immigrants have the greatest proficiency shortly after immigration, followed by family‐based visa recipients, with refugees having the lowest proficiency. Other variables the same, these differences disappear by 3.5 years after immigration for speaking skills; and although they diminish, they persist longer for reading and writing skills. The variables generated from the model of destination‐language proficiency (such as schooling and age at migration) are, in part, predictions of visa category, but they are more important statistically for explaining proficiency.  相似文献   
70.
Students in an academic training program were assessed for changes in their relationship and intervention skills following completion of the program. Positive improvements were found on some measures but not all. Additionally, trainee variables such as previous clinical experience. gender, age, marital stauts and scores on standardized admission tests were examined in relation to trainees' skills changes. Trainee characteristics were unrelated to changes in intervention skills. However, a number of relationships were found between trainee characteristics and changes in relationship skills.  相似文献   
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