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We estimate the size of the African American population in five-year age groups at census dates from 1930 to 1990 using a three-part strategy. For cohorts born after 1935, we follow the U.S. Census Bureau in using classical demographic analysis. To estimate the size of cohorts born before 1895, we use extinct-generation estimates. For remaining cohorts, we implement an age/period/cohort model of census counts. All approaches are applied to a data set in which the age distribution of deaths has been corrected for age misreporting. Results provide strong confirmation of the basic validity of Census Bureau estimates of census undercounts for African Americans while extending estimates to new cohorts and periods. Our estimates are less consistent with an historical series prepared by Coale and Rives (1973).  相似文献   
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Despite the central role of women drug users in escalating AIDS statistics, there is still a limited number of studies that examine the roles of gender and drug use type in HIV seroprevalence. This lacuna in the research literature has led to significant gaps in researchers' understanding of how and to what extent women may differ in their drug-using and HIV risk behaviors compared to their better-studied male counterparts. This study, derived from a sample of 3,555 out-of-treatment drug users residing in three South Florida urban and rural communities, attempts to compare the drug usage and needle and sexual risk behaviors of male and female drug users that put them at risk for HIV infection. The overall seropositivity rate for women drug users was 26.5% compared to 19.5% for their male counterparts. Results of multivariate analyses indicate that females compared to males were 1.4 times more likely to be HIV seropositive. Risk behaviors associated with this elevated seropositivity include living arrangements, homeless status, drug use, sexual trading behaviors, and history of STDs. Furthermore, there was a strong linear relationship between drug use type and HIV seroprevalence among women drug users. Compared to those who were neither crack smokers nor injectors of illicit drugs, those who were crack smokers only were 2 times more likely to be HIV seropositive, while those who were both crack smokers and injectors were 5 times more likely to be HIV seropositive, and those who were injectors only were 6 times more likely to be HIV seropositive. These findings indicate that among women, drug abuse and its associated risk behaviors, increase the vulnerability of this population for HIV and thus render them an extremely important priority population on which to focus HIV prevention and public health efforts and programs.  相似文献   
176.
Although one of the most marked demographic trends observed over the twentieth century is the increased rate of divorce, relatively little research has explored the effects of these changing marital patterns in the context of an aging society. Using a sample of lone elderly parents and their adult children, we analyze the direct and indirect effects of marital disruption on four important dimensions of intergenerational transfers: coresidence, financial assistance, adult children's provision of informal care, and parental purchase of paid care. Our findings suggest that divorce has deleterious effects on intergenerational transfers, particularly for elderly fathers. Remarriage further reduces exchange. Our results reveal that parents engage in lower levels of transfers with stepchildren relative to biological children. Moreover, intergenerational transfers are sensitive to characteristics of biological children but not to those of stepchildren. Taken together, these results suggest that exchange at the end of the life course continues to be adversely affected by marital disruption.  相似文献   
177.
Leaving school prematurely is often claimed to be among the most negative consequences of early marriage and pregnancy for girls in less developed countries. However, an analysis of the relative frequency with which these events actually occur or are named as reasons for leaving school reveals that, at least in the case of francophone Africa, they explain no more than 20 per cent of dropouts. To the extent that demographic events trump school or family factors as determinants of school-leaving, our data indicate that it is union formation--defined by the DHS as first marriage or cohabitation--rather than childbirth that is more likely to have this effect. 'Schoolgirl pregnancy' typically accounts for only between 5 and 10 per cent of girls' departures from school. Furthermore, the risks of leaving school because of pregnancy or marriage have declined over time with the decline in rates of early marriage and childbearing.  相似文献   
178.
Moving and union dissolution   总被引:1,自引:0,他引:1  
Boyle PJ  Kulu H  Cooke T  Gayle V  Mulder CH 《Demography》2008,45(1):209-222
This paper examines the effect of migration and residential mobility on union dissolution among married and cohabiting couples. Moving is a stressful life event, and a large, multidisciplinary literature has shown that family migration often benefits one partner (usually the man) more than the other Even so, no study to date has examined the possible impact of within-nation geographical mobility on union dissolution. We base our longitudinal analysis on retrospective event-history data from Austria. Our results show that couples who move frequently have a significantly higher risk of union dissolution, and we suggest a variety of mechanisms that may explain this.  相似文献   
179.
Although a consistent body of research has demonstrated that occupational segregation is highly consequential for women's economic standing, we know little about the processes that contribute to changes in levels of sex segregation. In this study, we examine those factors that contribute to changes in the percent of women in detailed occupational categories in the United States. Since we are most concerned with the economic consequences of this type of segregation, we analyze a group of high-paying, male-dominated occupations that, if better integrated, would contribute most to earnings equality. We find that occupations to which relatively high percentages of women aspired and occupations that are growing have been experiencing above-average increases in the percentage of women, while occupations characterized by male-stereotyped task profiles have been witnessing below-average increases. Additionally, our results suggest the presence of a ceiling effect: it is easier for women to break into male-dominated occupations initially than to sustain growth. Our analysis suggests that both supply and demand-side explanations provide insight into the processes contributing to increases in the occupations that we examine, although it can be very difficult to distinguish between supply and demand-side elements; indeed they may occur simultaneously.  相似文献   
180.
San Antonio, Texas, the seventh largest city in the United States, has experienced steady population growth, since the “boom” of the 1960s. Projected water shortages due to this growth were realized as early as the 1970s by city leaders and south-central Texas regional development decision makers. To reduce dependence on the already over-taxed, Edwards aquifer, a solution, the Applewhite Dam and Reservoir Project, was developed with wide acceptance by federal, state, and city leaders who regarded the project as a necessary measure for regional growth and development. However, opposition by taxpayer and environmental groups led to referendums of 1991 and 1994 in which voters blocked construction of the dam and reservoir leaving the city with limited options for water provision. This case study investigated the factors which led to a clear mismatch in communication between decision makers—those who were aware of the actual and quantifiable risk to the region in terms of reduced water supplies—and the general public, a population that did not have complete and/or adequate knowledge of their actual risk regarding future water shortages, nor, of solutions being developed, such as the Applewhite project. The findings from this case study indicate that when municipal leadership fails to adequately communicate risk regarding resource shortage to an affected public, as well as, openly planned solutions, that voters are likely to underestimate future impacts of water shortages, heed last-minute opposition, and reject long-standing, publicly proposed projects. The intent of this research is not to support either side in the Applewhite controversy, but to shed perspective on the process of adequately and effectively communicating future water needs to an at-risk population. Decision makers in cities across the United States who are faced with solving problems of limited resources needed by a large populace may be informed by the results of this research.  相似文献   
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