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71.
Healthy life expectancies are almost always calculated by using health data from cross-sectional surveys. This type of calculation is done partly because data from longitudinal surveys are not always available, and when they are available, they are collected at intervals that are longer than one year. In such cases, collecting health information retrospectively for the years skipped by the survey is useful. The main purpose of this paper is to show how retrospective health information can be used to estimate life expectancies in different health states. Healthy life expectancies are estimated with and without using data on retrospective health information, and the corresponding estimates are compared. The two sets of estimates are similar. We conclude that retrospectively assessed health information based on a one-year recall period can be used to estimate years of life in various health states and that estimates based on such information will closely approximate estimates based on concurrent health information. 相似文献
72.
Selective migration and health in the USA, 1984-93 总被引:1,自引:0,他引:1
Using data from the Panel Study of Income Dynamics, we investigated the impact of health on domestic migration within the USA. We find that, for men below 60 years of age, a move from the middle to the bottom of the health distribution reduces mobility by 32-40 per cent. Non-random attrition from the panel implies that these are lower bounds. By contrast, we find evidence that, among older men, there is higher mobility at the top and bottom of the health distribution than there is in the middle. For women, we find no evidence of a relationship between their own health and mobility, although spouse's health does affect the mobility of married women. 相似文献
73.
As an exploration of the potential impact of fears of discrimination against GLBTs in long-term health care settings, this study compared perceptions of GLBT persons and heterosexuals. A total of 132 GLBT persons and 187 heterosexuals living in Eastern Washington completed a survey that contained demographic questions and perceptions of discrimination in long-term care settings. Most respondents suspected that staff and residents of care facilities discriminate against GLBTs. GLBT respondents who believed that residents of care facilities are victims of discrimination were more likely to believe that they would have to hide their sexual orientation if admitted to a care facility. GLBT respondents were more likely than heterosexual respondents to believe that GLBTs do not have equal access to health care and social services, that GLBTs residents of care facilities are victims of discrimination, that GLBT sensitivity training programs would benefit staff and residents of care facilities, and that GLBT retirement facilities would be a positive development for older GLBTs. This study is offered as a preliminary investigation of concerns about GLBT discrimination in health care settings, how concerns are expressed, and the implications of those concerns for health care needs. 相似文献
74.
75.
The purpose of this paper is to examine the role of housing prices in the outcome of the 2008 U.S. presidential election. Based on data for the 50 states, this study postulates a multivariate model in which the impact of home values is exposed while controlling for other explanatory factors might have exerted independent effects on the Democratic victory. Results of estimation indicate a significant inverse effect of property price appreciation on Democratic votes. 相似文献
76.
Jana Kreppner Michael Rutter Robert Marvin Thomas O'Connor Edmund Sonuga‐Barke 《Social Development》2011,20(1):1-16
We set out to explore the meaning of the attachment categories in the Cassidy/Marvin strange situation procedure, as employed in the home, using data from a longitudinal study of children adopted into UK families up to the age of 42 months from Romanian institutions, and of adopted children without the experience of institutional care––both groups being assessed at 4 and 6 years of age. Inter‐rater reliability was found to be good. Security (meaning the use of the parent as a secure base and no negative behavior on reunion) was the modal categorical rating in both the institution‐reared and comparison groups, but the category of anomalous non‐normative behavior (meaning a lack of any ordered attachment behavior as covered by the standard ratings), previously labeled ‘insecure‐other’, was more common in the institution‐reared children. Because this was unassociated with the usual manifestations of insecurity (such as avoidance or resistance) and because it was largely evident in interactions with the stranger, it is concluded that the adjective ‘insecure’ was not appropriate. Although this ‘insecure‐other’ category was associated with disinhibited attachment as reported by parents (meaning a lack of differentiation among adults, a willingness to go off with strangers and a lack of checking back with parents in anxiety‐provoking situations), it did not prove to be a good index of disinhibited attachment because changes over time in the ‘insecure‐other’ category were not associated with changes in the rate of disinhibited attachment. Also, whereas the rate of ‘insecure‐other’ fell markedly in the institution‐reared group between 4 and 6 years of age, it rose in the comparison group, raising queries over its meaning. 相似文献
77.
Adaptations are psychological and behavioral mechanisms designed through evolution to serve specific purposes ultimately related to reproductive success. Although adaptations are inherently functional, in some cases their operation can nevertheless cause personal and social dysfunction. We describe a theoretical framework for understanding, predicting, and reducing the dysfunctional consequences of psychological adaptations. We discuss three general sources of dysfunction: a) the existence of adaptive tradeoffs, b) mismatches between current environments and ancestral environments, and c) individual differences. The paper applies this framework primarily to the topic of social anxiety, a psychological phenomenon marked by concerns pertaining to social rejection and embarrassment. Although social anxiety can serve useful functions, it can also involve excessive worry, negative affect, and avoidance of social situations, leading to significant distress and social impairment. We consider sources of dysfunction in social anxiety and discuss implications for policy, including recommendations for psychological, situational, and biological interventions. We also discuss broader applications of this theoretical framework to other areas of social life. 相似文献
78.
Michael R. Elliott Nicolas Stettler 《Journal of the Royal Statistical Society. Series C, Applied statistics》2007,56(1):63-78
Summary. We consider the problem of obtaining population-based inference in the presence of missing data and outliers in the context of estimating the prevalence of obesity and body mass index measures from the 'Healthy for life' study. Identifying multiple outliers in a multivariate setting is problematic because of problems such as masking, in which groups of outliers inflate the covariance matrix in a fashion that prevents their identification when included, and swamping, in which outliers skew covariances in a fashion that makes non-outlying observations appear to be outliers. We develop a latent class model that assumes that each observation belongs to one of K unobserved latent classes, with each latent class having a distinct covariance matrix. We consider the latent class covariance matrix with the largest determinant to form an 'outlier class'. By separating the covariance matrix for the outliers from the covariance matrices for the remainder of the data, we avoid the problems of masking and swamping. As did Ghosh-Dastidar and Schafer, we use a multiple-imputation approach, which allows us simultaneously to conduct inference after removing cases that appear to be outliers and to promulgate uncertainty in the outlier status through the model inference. We extend the work of Ghosh-Dastidar and Schafer by embedding the outlier class in a larger mixture model, consider penalized likelihood and posterior predictive distributions to assess model choice and model fit, and develop the model in a fashion to account for the complex sample design. We also consider the repeated sampling properties of the multiple imputation removal of outliers. 相似文献
79.
The EPA Health Risk Assessment of Methylcyclopentadienyl Manganese Tricarbonyl (MMT) 总被引:1,自引:0,他引:1
This paper describes the U.S. Environmental Protection Agency's assessment of potential health risks associated with the possible widespread use of a manganese (Mn)-based fuel additive, methylcyclopentadienyl manganese tricarbonyl (MMT). This assessment was significant in several respects and may be instructive in identifying certain methodological issues of general relevance to risk assessment. A major feature of the inhalation health risk assessment was the derivation of Mn inhalation reference concentration (RfC) estimates using various statistical approaches, including benchmark dose and Bayesian analyses. The exposure assessment component used data from the Particle Total Exposure Assessment Methodology (PTEAM) study and other sources to estimate personal exposure levels of particulate Mn attributable to the permitted use of MMT in leaded gasoline in Riverside, CA, at the time of the PTEAM study; on this basis it was then possible to predict a distribution of possible future exposure levels associated with the use of MMT in all unleaded gasoline. Qualitative as well as quantitative aspects of the risk characterization are summarized, along with inherent uncertainties due to data limitations. 相似文献
80.
Gray George M. Allen Jon C. Burmaster David E. Gage Stuart H. Hammitt James K. Kaplan Stanley Keeney Ralph L. Morse Joseph G. North D. Warner Nyrop Jan P. Stahevitch Alina Williams Richard 《Risk analysis》1998,18(6):773-780
The North American Free Trade Agreement (NAFTA) and the General Agreement on Tariffs and Trade (GATT) have focused attention on risk assessment of potential insect, weed, and animal pests and diseases of livestock. These risks have traditionally been addressed through quarantine protocols ranging from limits on the geographical areas from which a product may originate, postharvest disinfestation procedures like fumigation, and inspections at points of export and import, to outright bans. To ensure that plant and animal protection measures are not used as nontariff trade barriers, GATT and NAFTA require pest risk analysis (PRA) to support quarantine decisions. The increased emphasis on PRA has spurred multiple efforts at the national and international level to design frameworks for the conduct of these analyses. As approaches to pest risk analysis proliferate, and the importance of the analyses grows, concerns have arisen about the scientific and technical conduct of pest risk analysis. In January of 1997, the Harvard Center for Risk Analysis (HCRA) held an invitation-only workshop in Washington, D.C. to bring experts in risk analysis and pest characterization together to develop general principles for pest risk analysis. Workshop participants examined current frameworks for PRA, discussed strengths and weaknesses of the approaches, and formulated principles, based on years of experience with risk analysis in other setting and knowledge of the issues specific to analysis of pests. The principles developed highlight the both the similarities of pest risk analysis to other forms of risk analysis, and its unique attributes. 相似文献