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931.
Few studies have examined the effects of early life conditions on the timing of the onset of heart disease. We use the remarkable
example of a representative sample of the population of older Puerto Ricans aged 60– 74 who lived in the countryside during
childhood (n = 1,438) to examine the effects of seasonal exposures to poor nutrition and infectious diseases during late gestation on
the timing of the onset and the probability of ever experiencing adult heart disease. Cox and log logistic hazard models controlling
for childhood conditions (self-reported childhood health status and socioeconomic status [SES], rheumatic fever, and knee
height) and adult risk factors (adult SES, obesity, smoking, texercise, and self-reported diabetes) showed that the risk of
onset of heart disease was 65% higher among those born during high-exposure periods compared with unexposed individuals. However,
there were no significant differences in median time of onset for those ever experiencing heart disease. As a comparison,
we found that there were no significant seasonality effects for those who lived in urban areas during childhood. We conclude
that early exposures in utero have important ramifications for adult heart disease among the older Puerto Rican population.
We show, however, that while exposure is associated with the probability of ever experiencing adult heart disease, it is not
associated with the timing of onset among those who do experience it. 相似文献
932.
We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield
mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were
statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality
from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run
health follow-ups of the interaction between stress and social networks in a human population in which both stress and social
networks are arguably exogenous. 相似文献
933.
Many important questions and theories in demography focus on changes over time, and on how those changes differ over geographic
and social space. Space-time analysis has always been important in studying fertility transitions, for example. However, demographers
have seldom used formal statistical methods to describe and analyze time series of maps. One formal method, used widely in
epidemiology, criminology, and public health, is Knox’s space-time interaction test. In this article, we discuss the potential
of the Knox test in demographic research and note some possible pitfalls. We demonstrate how to use familiar proportional
hazards models to adapt the Knox test for demographic applications. These adaptations allow for nonrepeatable events and for
the incorporation of structural variables that change in space and time. We apply the modified test to data on the onset of
fertility decline in Brazil over 1960–2000 and show how the modified method can produce maps indicating where and when diffusion
effects seem strongest, net of covariate effects. 相似文献
934.
This research investigates three different indicators of at-risk socio-demographic conditions including dropping out of high
school, being idle, and being in highest-risk idleness among non-immigrant persons aged 19–24. Using data from the 2000 US
Census, our results detail the differentials in these characteristics for 30 different racial/ethnic groups that are further
broken down by gender. The findings indicate a wide range in the prevalence of these at-risk socio-demographic conditions.
Groups that tend to be the most at-risk in terms of these indicators include African Americans, Cambodians, Laotians, Native
Americans, other Hispanic whites, and white Mexicans. With the exception of the other Pacific Islander and Thai, young women
have lower high school dropout rates than do young men. However, young women are substantially more likely than young men
to be idle which we define as not being in school, the labor force, or the military. After defining highest-risk idleness
as never-married persons without children who are idle, however, the rates are slightly lower for young women than for young
men. 相似文献
935.
Sven Drefahl 《Demography》2010,47(2):313-326
I use hazard regression methods to examine how the age difference between spouses affects their survival. In many countries,
the age difference between spouses at marriage has remained relatively stable for several decades. In Denmark, men are, on
average, about three years older than the women they marry. Previous studies of the age gap between spouses with respect to
mortality found that having a younger spouse is beneficial, while having an older spouse is detrimental for one’s own survival.
Most of the observed effects could not be explained satisfactorily until now, mainly because of methodological drawbacks and
insufficiency of the data. The most common explanations refer to selection effects, caregiving in later life, and some positive
psychological and sociological effects of having a younger spouse. The present study extends earlier work by using longitudinal
Danish register data that include the entire history of key demographic events of the whole population from 1990 onward. Controlling
for confounding factors such as education and wealth, results suggest that having a younger spouse is beneficial for men but
detrimental for women, while having an older spouse is detrimental for both sexes. 相似文献
936.
Alisson F. Barbieri Edson Domingues Bernardo L. Queiroz Ricardo M. Ruiz José I. Rigotti José A. M. Carvalho Marco F. Resende 《Population and environment》2010,31(5):344-370
This research contributes to an understanding of the relationship between climate change, economic impacts and migration.
We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven
by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular
relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels
of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately,
the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary
economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact
severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country.
Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian
public policy and planning. 相似文献
937.
Aaron M. McCright 《Population and environment》2010,32(1):66-87
This study tests theoretical arguments about gender differences in scientific knowledge and environmental concern using 8 years
of Gallup data on climate change knowledge and concern in the US general public. Contrary to expectations from scientific
literacy research, women convey greater assessed scientific knowledge of climate change than do men. Consistent with much
existing sociology of science research, women underestimate their climate change knowledge more than do men. Also, women express
slightly greater concern about climate change than do men, and this gender divide is not accounted for by differences in key
values and beliefs or in the social roles that men and women differentially perform in society. Modest yet enduring gender
differences on climate change knowledge and concern within the US general public suggest several avenues for future research,
which are explored in the conclusion. 相似文献
938.
This research examines land use change in Israel––an intriguing but understudied setting with regard to population–environment
dynamics. While Israel is fairly unique with regard to its combined high levels of economic prosperity and high population growth, this case study has relevance for developed countries and regions (like the south and southwest regions
of the USA) which must balance population growth and urban development with open space conservation for ecosystem services
and biological diversity. The population–land development relationship is investigated during the period from 1961 to 1995
at three spatial scales: national, regional (six districts), and local (40 localities). There is a positive correlation between
population growth and land development rates at the national scale, and while remaining positive, the strength of the relationship
varies greatly at regional and local scales. The variation in population–land use dynamics across scales is used to garner
insight as to the importance of geography, policy and historical settlement patterns. 相似文献
939.
C.-Y. Cynthia Lin 《Population and environment》2010,31(4):255-281
This article examines whether natural disasters affect fertility—a topic little explored but of policy importance given relevance
to policies regarding disaster insurance, foreign aid, and the environment. The identification strategy uses historic regional
data to exploit natural variation within each of two countries: one European country—Italy (1820–1962), and one Asian country—Japan
(1671–1965). The choice of study settings allows consideration of Jones’ (The European miracle, Cambridge University Press,
Cambridge, 1981) theory that preindustrial differences in income and population between Asia and Europe resulted from the
fertility response to different environmental risk profiles. According to the results, short-run instability, particularly
that arising from the natural environment, appears to be associated with a decrease in fertility—thereby suggesting that environmental
shocks and economic volatility are associated with a decrease in investment in the population size of future generations.
The results also show that, contrary to Jones’ (The European miracle, Cambridge University Press, Cambridge, 1981) theory,
differences in fertility between Italy and Japan cannot be explained away by disaster proneness alone. Research on the effects
of natural disasters may enable social scientists and environmentalists alike to better predict the potential effects of the
increase in natural disasters that may result from global climate change. 相似文献
940.
The advent of a continuously updated Master Area File (MAF) following the 2000 census represents an information resource that
can be tapped for purposes of developing timely, cost-effective, and precise population estimates for even the smallest of
geographical units (e.g., census blocks). We argue that the MAF can be enhanced (EMAF) for these purposes. In support of our
argument we describe a set of activities needed to develop EMAF, each of which is well within the current capabilities of
the U.S. Census Bureau and discuss various costs and benefits of each. We also describe how EMAF would provide population
estimates containing a wide range of demographic (e.g., age, race, and sex) and socio-economic characteristics (e.g., educational
attainment, income, and employment). As such, it could largely negate and eliminate the need for many of the traditional demographic
methods of population estimation and possibly reduce the number of sample surveys. We identify important challenges that must
be surmounted in order to realize EMAF and make suggestions for doing so. We conclude by noting that the idea of the EMAF
could be of interest to other countries with MAF files and strong administrative records systems that, like the United States,
are facing the challenge of producing good population information in the face of increasing census costs. 相似文献