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Jennifer M. Cameron MS Natalie Heidelberg MS Lisa Simmons BS Sarah B. Lyle BS Kathakali Mitra-Varma PhD Chris Correia PhD 《Journal of American college health : J of ACH》2013,61(5):499-506
Abstract Objectives, Participants, Methods: Drinking game participation has increased in popularity among college students and is associated with increased alcohol consumption and alcohol-related problems. The current study investigated drinking game participation among 133 undergraduates attending National Alcohol Screening Day (NASD) in April of 2007. Results: A large percentage of the sample reported lifetime (77%) and recent (52%) drinking game participation. Males were more likely to report recent participation and reported higher levels of consumption while playing drinking games. Drinking game participants were more likely to experience a range of alcohol-related problems, and the relationship between drinking game participation and alcohol-related problems was mediated by weekly alcohol consumption. Conclusions: These results suggest that drinking game participation is a risk factor for elevated levels of alcohol consumption and alcohol-related problems. Programs should be developed to educate students about the risks of drinking game participation, and prevention programs like NASD should address drinking games. 相似文献
33.
Structure and composition of woody plants in urban forest remnants with different adjacent land-use and slope aspect 总被引:1,自引:0,他引:1
The plant community in the karst forest is influenced by mesoclimatic conditions, such as temperature and humidity and these
conditions are in turn influenced by topographic features. Urban areas adjacent to karstic forest remnants also have the potential
to influence mesoclimatic variables and may serve as a source of exotic species. We described the temperature and relative
humidity of karstic forest remnants at slopes with combinations of either southeast (SE) or northwest (NW) aspect, and adjacent
to either urban (URB) or secondary forest (SF). We also compared forest structure and composition on these slopes to understand
the interaction between forest aspect and adjacent land use on the plant community. URB-SE slopes had highest temperature
and lowest humidity among all adjacent land use-aspect combinations. Understory species in SE slopes had similar richness
and diversity independently of adjacent land use, however within NW aspect, slopes adjacent to urban areas showed higher values
than slopes adjacent secondary forest. Canopy trees species in slopes adjacent to secondary forest were more diverse and rich
in SE than in NW, although no differences between aspects were detected within URB-adjacent slopes. Understory species composition
was different among the four land use-aspect combinations. However, composition of canopy trees species was different only
between aspect types. Most exotic species in the sites were associated with previous agricultural practices and not with current
land use. Our results show a temporal and spatial influence of anthropogenic systems on the plant community in karstic forest
remnants at a suburban area of Puerto Rico. 相似文献
34.
Population and Deforestation in Costa Rica 总被引:5,自引:0,他引:5
This paper addresses a central debate in research and policy on population and environment, namely the extent to which rapid population growth is associated with the massive deforestation currently underway in the tropics. We utilize the experience of Costa Rica during the last forty years to illustrate what the main issues are, discuss the history of deforestation in that country, and present results from conventional regression methods and from the application of spatial analyses. These analyses enable us to estimate the magnitude of the relation between population and deforestation and to identify the factors that are responsible for the linkage between them. 相似文献
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Ileana Baldi Eva Pagano Paola Berchialla Alessandro Desideri Alberto Ferrando Franco Merletti 《Journal of applied statistics》2013,40(2):298-310
Highly skewed outcome distributions observed across clusters are common in medical research. The aim of this paper is to understand how regression models widely used for accommodating asymmetry fit clustered data under heteroscedasticity. In a simulation study, we provide evidence on the performance of the Gamma Generalized Linear Mixed Model (GLMM) and log-Linear Mixed-Effect (LME) model under a variety of data-generating mechanisms. Two case studies from health expenditures literature, the cost of strategies after myocardial infarction randomized clinical trial on the cost of strategies after myocardial infarction and the European Pressure Ulcer Advisory Panel hospital prevalence survey of pressure ulcers, are analyzed and discussed. According to simulation results, the log-LME model for a Gamma response can lead to estimations that are biased by as much as 10% of the true value, depending on the error variance. In the Gamma GLMM, the bias never exceeds 1%, regardless of the extent of heteroscedasticity, and the confidence intervals perform as nominally stated under most conditions. The Gamma GLMM with a log link seems to be more robust to both Gamma and log-normal generating mechanisms than the log-LME model. 相似文献
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The effects of the pace of childbearing and breastfeeding practices on infant mortality have rarely been considered together. In this paper, we design and use a set of methodological tools to test a variety of hypotheses postulating the effects of breastfeeding and pace of childbearing on mortality in infancy and early childhood, the mechanisms through which those effects operate, and the contingencies that strengthen or weaken them. The strong effects of both length of breastfeeding and the pace of childbearing on the risks of child death suggest that neither of them exerts an impact on mortality totally mediated by the other. Social and demographic factors (such as age of child, education of mother, and region of residence) also condition the impact of breastfeeding and pace of childbearing on mortality. 相似文献
40.
Alberto Palloni 《Demography》1979,16(3):455-473
The paper presents new estimates of infant mortality for Colombia and El Salvador for the years 1950--1970. These estimates are obtained by using a technique which improves on Brass's method in that it suppresses the assumption of constant mortality and introduces instead assumptions about linear and nonlinear changes in mortality risks affecting various cohorts of individuals. 相似文献