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991.
Driving Under the Influence of Risky Peers: An Experimental Study of Adolescent Risk Taking
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Luna C. Muñoz Centifanti Kathryn L. Modecki Susanne MacLellan Helen Gowling 《Journal of research on adolescence》2016,26(1):207-222
Both passive and active social influences may affect adolescents' dangerous driving. In this study, we used an experimental paradigm to delineate these two influences with actual peers. Adolescents completed a simulated driving task, and we measured risk preferences of each member of the peer group. We used hierarchical linear modeling to partition variance in risky decisions. Adolescents experienced many more crashes when they had “passengers” present who reported a strong preference for risk taking and who actively provided decision‐making guidance. Although youth in the passive peer condition were also influenced by the riskiness of their peers, this relation was less strong relative to the active condition. We discuss the need for interventions focussing on active and passive peer influence. 相似文献
992.
Richard A. Brandon-Friedman Hea-Won Kim 《Journal of gay & lesbian social services》2016,28(4):292-316
This study examined the impact of five domains of social support (a campus group for individuals who identify as a sexual minority, family, friends, significant others, and faith communities) on eight aspects of sexual minority identity development (identity uncertainty, internalized homonegativity, identity affirmation, acceptance concerns, identity superiority, concealment motivation, identity centrality, and difficulty in the identity development process). Support from a sexuality-specific campus group was the strongest predictor, followed by support from family members. Supports from friends and significant others had no significant impact on any aspect of sexual minority identity development, while faith community support was not correlated with identity development. Identifying as lesbian, bisexual, or as another sexual minority compared to identifying as gay also impacted sexual minority identity development. 相似文献
993.
Recent studies indicate that treatment-seeking problem gamblers display elevated rates of ADHD and that adolescents who screen positive for ADHD are more likely to engage in gambling, develop gambling problems, and experience a greater severity in gambling problems. This study aimed to (a) compare the prevalence of ADHD in treatment-seeking problem gamblers to the general population; (b) investigate the relationships between ADHD and problem gambling severity, cluster B personality disorders, motor impulsivity, alcohol use, substance use, gender, and age; and (c) investigate the degree to which these factors moderate the relationship between ADHD and problem gambling severity. Participants included 214 adults (154 males, 58 females, 2 unspecified) who sought treatment for their gambling problems at a specialist gambling agency in Melbourne, Australia. Almost one-quarter (24.9 %) of treatment-seeking problem gamblers screened positively for ADHD, which was significantly higher than the 14 % prevalence in a community sample. ADHD was significantly positively correlated with problem gambling severity, motor impulsivity, and cluster B personality disorders, but was not associated with alcohol and substance use, gender or age. None of the factors significantly moderated the relationship between ADHD and problem gambling severity. These findings suggest that a considerable proportion of treatment-seeking problem gamblers report ADHD and that their clinical profile is complicated by the presence of high impulsivity and cluster B personality disorders. They highlight the need for specialist gambling agencies to develop screening, assessment, and management protocols for co-occurring ADHD to enhance the effectiveness of treatment. 相似文献
994.
Constructed wetlands in urban environments may be used by urban amphibian populations for breeding. Yet, few studies have examined the performance of young-of-the-year from created wetlands even though the success of terrestrial life stages is directly linked to the performance of individuals at the egg and larval stage. We assessed how early-stage amphibians developing within constructed stormwater wetlands compared in body size (one metric of performance) to those in nearby natural wetlands. We conducted surveys for wood frog, Lithobates sylvaticus, larvae and young-of-the-year metamorphs at 13 wetlands located in the City of Edmonton, Alberta, Canada and compared metamorph size (a useful metric for fitness and reproductive success) between constructed stormwater and two types of natural wetlands. We related body size to within-wetland parameters (reflecting water chemistry, thermal regimes and physical characteristics) and used an information-theoretic approach to identify predictors of metamorph body size. Abundances of egg masses, larvae and metamorphs were generally lower at stormwater than natural wetlands. Metamorphs exhibited larger body size in stormwater wetlands compared to natural wetlands. Low metamorph abundances and cool, stable water temperatures best explained large body size in stormwater metamorphs. We propose that with increasing urbanization and associated construction of artificial wetlands, size benefits in early developmental stages may help individuals cope with reduced habitat suitability in the terrestrial environment. 相似文献
995.
Tropical forested ecosystems provide multiple ecosystem services to rural and urban landscapes, with carbon storage gaining particular attention. Deforestation due to rural-urban transitions may lead to a reduction in carbon storage ability. Coastal mangrove forests are particularly at risk from deforestation due to their location in the rapidly urbanizing coastal zone, and the city state of Singapore is an extreme example, losing as much as 90 % of its original mangrove cover due to land reclamation and reservoir construction. Knowledge of mangrove ecosystem services may allow better conservation, restoration and incorporation of remaining mangrove patches into the urban landscape. Focusing on the regulating ecosystem service of carbon storage, mangrove carbon stocks have been estimated for Singapore using a combination of field and remote sensing techniques. Biomass carbon showed substantial spatial variation, with old, contiguous mangrove patches containing a higher density of biomass carbon than fragmented, river-fringing or restored mangroves. In total, national biomass carbon equated to 116,117.1 megagrams of carbon (Mg C), and a coarse estimate of the total carbon stock (including soil carbon) suggests that Singapore’s mangroves may store 450,571.7 Mg C. While lower than other regional estimates focused on natural, oceanic mangroves, this is a significant carbon stock for a disturbed, urban mangrove system, and may be equivalent to the average annual carbon emissions of 621,000 residents. This analysis, alongside a review of other urban forest studies, highlights the importance of forested ecosystems such as mangroves in providing a carbon storage ecosystem service to urban areas. 相似文献
996.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals. 相似文献
997.
998.
Sarah Bartos Smith Jenny E. McKay Jennifer K. Richardson Amy A. Shipley Michael T. Murphy 《Urban Ecosystems》2016,19(2):577-598
Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (SA). We developed a stochastic model that combined F and SA with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but SA did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (SD = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, SD reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability. 相似文献
999.
Vikki C. Terrile 《Journal of Children and Poverty》2016,22(2):133-146
While public libraries are often used by people experiencing homelessness, the value of libraries for homeless children and families has been understudied. This brief explores how public libraries can support families experiencing homelessness and how they can engage with other service providers and agencies as part of a collective impact model to support a wide array of families’ needs. Since homelessness is the result of many interconnected social and economic conditions, this paper also examines how awareness and a lack of knowledge of these factors can impact service delivery and expectations. Finally, a case study of how the Queens Library in New York City engages with family shelters to support children’s learning and exploration is included to provide best practice examples. 相似文献
1000.
Fiona M. Brooks Kayleigh L. Chester Nigel C. Smeeton Neil H. Spencer 《Journal of youth studies》2016,19(1):36-54
The geographies of the current generation of young people are markedly distinct from previous generations by virtue of their access to a virtual playground. The vast majority of young people now engage in video gaming as a leisure activity. Drawing on findings from the 2009/2010 WHO Health Behaviour in School-aged Children study this paper set out to investigate the factors that might be associated with higher levels of video gaming. Information was collected from 4404 school students aged 11, 13 and 15 years, using anonymised self-completed questionnaires. Higher usage was defined as game play exceeding two hours a day. Separate analyses were conducted for boys and girls. For both genders higher levels of game playing was associated with early adolescence, opposite sex friends and minimal parental mediation. Bullying and going to bed hungry were associated with higher usage for boys only, while life satisfaction and family activities were linked to girls’ game playing only. Parents were identified as effective mediators of young people’s video game usage. The study identified gendered motivations for higher levels of game play, suggesting different interventions for boys and girls may be required in order for young people to create a balanced approach to video gaming. 相似文献