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831.
Millions of listeners tune in to Internet-based audio-on-demand programming (commonly known as audio podcasts). College students represent a large and influential group of consumers but little is known about this primary audience's podcast listening choices and related opinions. This research was organized within the uses and gratifications perspective and involved an online survey of college students who identified as podcast listeners. Results showed most collegiate listeners spent no more than an hour a month listening to podcasts, and fewer than half reported listening to all the episodes they downloaded. Most listeners found podcasts fun and entertaining and said they enjoy sharing what they have heard with peers. Respondents reported clearly identified program genre preferences, and reported ‘multitasking’ in a variety of specific ways while listening. This research does not attempt to answer all questions about the college student podcast audience, but it is a starting point for further study into this important user group. Recommendations for future research are offered.  相似文献   
832.
The purpose of this prospective case report was to evaluate the use of a keyboard platform device that uses continuous passive motion (CPM) on vascular flow to the hand for clerical employees who perform daily keyboarding tasks. Subjects were two female volunteers, one symptomatic of carpal tunnel syndrome (CTS), who were employed in clerical positions and perform daily keyboarding tasks for most of their workday. Data collection consisted of baseline and follow-up measurements at 6 weeks, including: 1) screening for symptoms based on the Carpal Tunnel Function Disability Form, 2) evaluation using standard physical therapy examination and assessment techniques, including modified Semmes- Weinstein monofilament testing, 3) a typing productivity test, and 4) Doppler ultrasound examination to quantify vascular flow at the wrist. Results revealed that both subjects demonstrated an overall increase in both radial and ulnar blood flow velocity with no decrement in typing productivity. The symptomatic subject also demonstrated an overall improvement of 10 wpm in the typing tests, a decrease in her disability score and symptom severity, and improvement in function. Results suggest that use of CPM as a non-intrusive ergonomic intervention may be used to treat, as well as prevent, carpal tunnel-like symptoms in those who keyboard.  相似文献   
833.
Urbanization leads to long-term modification of landscapes by habitat loss, fragmentation, and the creation of new habitats. Species’ distributions respond to these modifications of habitat availability, but the combination of parameters and scale at which habitat alteration most strongly influences species distributions is poorly understood. We evaluated responses of neotropical migratory birds, a group known to be sensitive to habitat modification, across a gradient of urbanization in the southeastern United States. Thirteen Breeding Bird Survey routes, each with 40 to 50 point counts, were used to quantify species richness across the gradient of urbanization extending from downtown areas of Columbus, GA to natural woodlands. Buffers of 100, 200, and 1000 m radii were constructed from remote images around each counting point to quantify land-use with the goal of evaluating land-use parameters and scales that best described spatial variation in migrant bird species richness. Within each buffer we quantified the proportion of each cover type and within the 1000 m buffers we included several configuration parameters. We used an information-theoretic approach to separate models whose predictor variables were land-use parameters. Because measures of landscape configuration were all correlated with urban cover, these variables were entered separately. In 2002, the best model was composed of large-scale urban cover (negative effect) and mid-scale mixed hardwoods (negative and positive effect) and transitional cover (negative and positive effect) as well as the interaction between the latter two terms (positive effect). In 2003, the best model was composed of weighted edge density (negative effect), mid-scale mixed hardwood cover (negative and positive effect) and large scale transitional cover (positive effect) and the interaction between mixed hardwoods and weighted edge density (positive effect). Our results indicate that large scale habitat attributes influence the local species richness of migrant birds more than smaller scales. These results also indicate that urbanization, through increased urban cover or increasing edge contrast, has strong negative effects on species richness. Our findings support the contention that the conservation value of small woodlots in urban settings may be minimal and suggest that conservation of migratory birds will be best achieved by giving higher priority to sites where urban cover is still low and by preserving large areas of “green space” in urbanizing landscapes. The negative influence of urban cover combined with relatively minor effects of non-urban habitats on distributions of neotropical migratory birds indicates that continued urbanization of landscapes is a serious concern for conservation efforts.  相似文献   
834.
Meyers MK  Heintze T  Wolf DA 《Demography》2002,39(1):165-179
Changing patterns of maternal employment, coupled with stronger work requirements for welfare recipients, are increasing the demand for child care. For many families, the cost of child care creates a financial burden; for mothers with low incomes and those who are former welfare recipients, these costs may be an insurmountable barrier to employment or economic self-sufficiency. Despite increased public spending in this area, the receipt of any child care subsidy appears to be a relatively rare and uncertain event. In this study, we use data from a sample of low-income single mothers (current and recent welfare recipients in California) to estimate the probability of their receiving child care subsidies and the effect of this probability on labor market activity.  相似文献   
835.
This study examines the distribution of total, unimpaired, and impaired life for several groups of older women defined by race, education, and marital history. Using data from the 1984-1990 Longitudinal Study of Aging, we model transitions among functional statuses using discrete-time Markov chains, and use microsimulation to produce summary indices of active life. Remaining years of life and the proportion of remaining years with disability vary substantially, both within each group of women studied and between pairs of groups. Of all groups studied, never-married, more-educated white women live the longest, healthiest lives. Ever-married nonwhite women with low education have the shortest life expectancy, and experience the most disability. Our findings show that life expectancy is an incomplete indicator of the time women, in particular sub-groups, can expect to live with and without impairment. These findings highlight the heterogeneity of disability processes and life expectancy for older women.  相似文献   
836.
The impact of schools and school programs upon adolescent sexual behavior   总被引:1,自引:0,他引:1  
Because most youth are enrolled in school for many years before they initiate sex and when they initiate sex, schools have the potential for reducing adolescent sexual risk-taking. This paper reviews studies which examine the impact upon sexual risk-taking of school involvement, school characteristics, specific programs in school that do not address sexual behavior, and specific programs that do address sexual risk-taking. Multiple studies support several conclusions. First, involvement in and attachment to school and plans to attend higher education are all related to less sexual risk-taking and lower pregnancy rates. Second, students in schools with manifestations of poverty and disorganization are more likely to become pregnant. Third, some school programs specifically designed to increase attachment to school or reduce school dropout effectively delayed sex or reduced pregnancy rate, even when they did not address sexuality. Fourth, sex and HIV education programs do not increase sexual behavior, and some programs decrease sexual activity and increase condom or contraceptive use. Fifth, school-based clinics and school condom-availability programs do not increase sexual activity, and either may or may not increase condom or contraceptive use. Other studies reveal that there is very broad support for comprehensive sex- and HIV-education programs, and accordingly, most youth receive some amount of sex or HIV education. However, important topics are not covered in many schools.  相似文献   
837.
In the United States, there exist a multitude of different approaches to reducing adolescent sexual risk-taking, unintended pregnancy, childbearing, and sexually transmitted disease, including HIV. While many of these approaches have some positive effects upon some outcomes (such as greater knowledge), only some of these programs actually delay the initiation of sex, increase condom or contraceptive use, and reduce unprotected sex among youth. This article summarizes a review of 73 studies and their respective programs, and describes four groups of programs which have reasonably strong evidence that they delay sex, increase condom or contraceptive use, or reduce teen pregnancy or childbearing. These four groups of programs include (a) sex and HIV education curricula with specified characteristics, (b) one-on-one clinician-patient protocols in health settings with some common qualities, (c) service learning programs, and (d) a particular intensive youth development program with multiple components.  相似文献   
838.
Visual sociology: Expanding sociological vision   总被引:1,自引:0,他引:1  
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839.
Local governments are under increasing pressure to effectively represent various political interests within communities. This study attempts to measure and explain city council member perceptions of representational and service delivery effectiveness of local governments for a sample of communities in Wisconsin. The authors hypothesize that variables from several categories are related to representational and service delivery effectiveness, and that these two variables are strongly related.  相似文献   
840.
In this paper we attempt to overcome several weaknesses of earlier field studies of the effect of international migration on sending communities. In general, these studies fail to employ representative samples of migrants, specify theoretical models of decision-making, or control for a variety of individual and household characteristics likely to affect how migrants dispose of their earnings, including sample selectivity. Representative samples of Mexican migrants from four sending communities are used to estimate a theoretical model that controls for a variety of individual, family, and trip characteristics; other stages of the analysis also control for sample selectivity. The findings suggest that migrant decision-making is strongly and consistently determined by social capital and community membership, with other variables playing ancillary roles in different decision processes. The propensities to save, remit, and invest productively generally rose as ties to the United States increased, and were generally higher in communities with well-developed local economies.  相似文献   
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