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991.
ABSTRACT

The experiences, including with environmental microaggressions, and well-being of trans* collegians remain an under-researched topic. In this mixed-methods study of a survey sample of 152 trans* collegians, multivariable regression findings suggest that the frequency of experiencing select trans* environmental microaggressions (e.g., not having access to comfortable bathrooms as a trans* person) are associated with increased risk for poorer academic outcomes (e.g., developmental challenges) but are not associated with mental health outcomes. Furthermore, interviews with 18 trans* collegians suggest that students face several systemic microaggressions, including difficulties advancing trans* inclusion. Various reactions, including paths of resistance, were identified. Implications are discussed.  相似文献   
992.
Urban forests provide valuable ecosystem services, but their long-term viability is often threatened by low tree recruitment due to seed and/or microsite limitation. Distinguishing between these two causes of low recruitment has important management implications, but has been little studied in urban environments. We tested for seed and microsite limitation in an urban forested park in Seattle, Washington, USA by adding conifer tree seeds and seedlings to experimental plots in which we manipulated microsite conditions by removing invasive ivy (Hedera spp.) and adding deadwood. We found that natural seed production was low, and adding seeds increased the number of observed seedlings. Furthermore, adding deadwood increased seedling survival, whereas removing Hedera did not have strong effects. Seed limitation is frequently addressed through management actions such as sowing seeds and transplanting seedlings, and our results suggest that such actions address a critical barrier to tree recruitment in urban forests. However, we also observed strong microsite limitation. At our study site, microsite limitation can be addressed primarily by adding deadwood and retaining coarse woody debris on site. Addressing microsite limitation may be a critical component of successful management efforts to improve tree recruitment in urban forests, and should not be overlooked. Furthermore, our study highlights the need for active monitoring and data analysis alongside management, since the most apparent threat (widespread cover of an invasive plant in this case) may not be the primary limit on suitable microsite conditions.  相似文献   
993.
Due to habitat fragmentation, resource disruption and pollution, urbanization is one of the most destructive forms of anthropization affecting ecosystems worldwide. Generally, human-mediated perturbations dramatically alter species diversity in urban sites compared to the surroundings, thus influencing the functioning of the entire ecosystem. We investigated the taxonomic and functional diversity patterns of the aquatic macroinvertebrate communities in tank bromeliads by comparing those found in a small Neotropical city with those from an adjacent rural site. Changes in the quality of detrital inputs in relation to lower tree diversity and the presence of synanthropic species are likely important driving forces behind the observed structural changes in the urban site. Leaf-litter processors (i.e., shredders, scrapers) were positively affected in the urban site, while filter-feeders that process smaller particles produced by the activity of the shredders were negatively affected. Because we cannot ascertain whether the decline in filter-feeders is related to food web-mediated effects or to competitive exclusion (Aedes aegypti mosquitoes were present in urban bromeliads only), further studies are necessary to account for the effects of intra-guild competition or inter-guild facilitation.  相似文献   
994.
Urban afforestation improves life quality in urban centers providing social and environmental benefits. Understanding growth of urban trees exposed to air pollution will support planning, managing and expanding urban areas. This approach intends to determine growth patterns of urban trees to support future urban planning. Non-destructive samples were collected from trees of Araucaria angustifolia (Bertol.) Kuntze in Araucaria city, Parana State, Brazil. Growth rings were related to pollutant concentrations and meteorological series. Growth reduction was observed except in the border areas of the city. Trees established during or after the period of industrialization incentives were most affected by air pollution, indicating that immature plants are more vulnerable. Sulphur dioxide and nitric oxide significantly affected growth of smaller trees. Those greater than 60 cm dbh did not demonstrate significant correlation with any identified pollutant. As the trees established before accentuated urbanization were less affected by air pollution, it is reinforced the importance of preserving remaining urban trees. We suggest that planning urban afforestation should precede industries placing. When urban planning is impossible, new planted trees should not be expected to grow as in free pollution areas, but they will still present satisfactory diameter increment, contributing to improve local urban environment.  相似文献   
995.
ABSTRACT

The article analyses the politics of ‘double discourse’ in relation to Roma that has evolved in contemporary neoliberal Europe. On the one hand, the double discourse promotes the integration, rights and equal opportunities of Roma, on the other, it denies recognition of, and ways to address, enduring structural violence and rising social insecurity. The article argues that the politics of ‘double discourse’, as a neoliberal approach towards Roma, is structured by two contradictory discourses that speak to different audiences, using duplicitous approaches to create anti-Roma consensus and maintain the critical difference and subordinated position of the racialised Romani populations in Europe. By studying the representation of Roma in the cases of so-called 'child theft' in Greece and Ireland, and in the recent ‘refugee crisis’, the paper identifies and discusses three dimensions of contemporary neoliberal double discourse: racialised de-Europeanisation, neoliberal undeservingness and (dis)articulation of citizenship.  相似文献   
996.
Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines, lacks a theoretical framework that synthesizes the diverse and important aspects of heterogeneity. This paper presents the concept of dynamic heterogeneity as a tool to explore how social and ecological heterogeneities interact and how they together act as both an outcome of past interactions and a driver future heterogeneity and system functions. To accomplish this goal, we relate heterogeneity to the fundamental concept of the human ecosystem. The human ecosystem concept identifies key processes that require operationalized models of dynamic heterogeneity in three process realms: the flow of materials, the assembly of urban ecosystem biota, and the locational choices humans make concerning land. We exemplify a specific dynamic model of heterogeneity in each of these realms, and indicate a range of complementary statistical approaches to integrate the drivers and outcomes of dynamic heterogeneity across the three realms. We synthesize a hierarchical framework for a theory of dynamic urban heterogeneity, noting its complementarity to other major urban theories and general model approaches. We hypothesize that human actions and structures amplify the dynamics of heterogeneity in urban systems.  相似文献   
997.
The voices of people experiencing poverty are underrepresented in social work research, public policy development, and practice interventions. This study explored the social class attributions of clients receiving poverty-related services through qualitative interviews. Findings reveal dynamic contributions of individual, environmental, and structural factors of social class positioning and significant stress and stigmatization associated with experiencing economic hardship. Participants indicate a sense of lived contradiction, viewing social class to be the result of fate while simultaneously endorsing individualistic attributions of poverty. Results have implications for social work research and practice, as well as poverty-related policy and program development.  相似文献   
998.
This study explores political consumerism motivations in an effort to understand the complex ways in which this lifestyle practice fits into the broader participation repertoires of young citizens. We begin by outlining the psychological motivations for political consumerism, and theorize how they might orient political consumers toward (and away from) online expressive, political, and civic participation. In particular, we examine how the desire to gratify distinct psychological needs shapes navigation of the digital media environment in search of information and connection, and how this, in turn, shapes participation. Results of a national survey of young adults show that value-expressive, social-identification, and social-approval motivations for green living relate differently to participation, and that online community embeddedness mediates these relationships. The findings suggest that connecting to likeminded others via digitally-enabled communities can transform individual concerns into collective concerns, and extend participation from the private spheres of everyday life into the public sphere.  相似文献   
999.
This article analyzes the social construction of border surveillance and policing in reality-based television. Utilizing content analytic methods to document and decode popular images of borders, mobility, and insecurity, it assesses three programs from Australia, the UK, and the United States. Despite claims of offering accurate and unfiltered depictions, the programs are ideological and provide visions of enforcement that reinforce stereotypes regarding the risks of permeable borders and exonerate intensive regimes of surveillance and securitization. Our findings suggest this occurs in three ways. First, the programs inflate the extent and seriousness of lawlessness associated with cross-border movement. Second, they offer individualistic explanations of crime that cite personal choices and pathologies as determinants. Finally, alongside neglecting their perspectives and interpretations of events, when compared to the reality of official statistics, the programs disproportionately feature suspected offenders as members of marginalized groups. The social and political implications of these findings are discussed.  相似文献   
1000.
Crowdsourcing platforms like Amazon’s Mechnical Turk and Crowdflower have been touted to be a cost-effective way to collect large amounts of behavioural data. Across four large-n studies, gambling-related behaviours, tendencies and traits among participants in these labour markets were examined. In Studies 1 and 2, both conducted on Crowdflower, problem gamblers (as measured by the benchmark Problem Gambling Severity Index) comprised 24.5% and 21.9% of participants, respectively. In Study 3, conducted on Mechanical Turk, problem gamblers comprised 9.0% of participants. In Study 4, a two-wave longitudinal study conducted on Crowdflower, problem gamblers comprised 13.5% of participants in wave one and 14.8% of participants in wave two. In Studies 2 and 3, strong convergent associations were demonstrated across various measures of problem gambling tendencies and general gambling involvement. Furthermore, it was demonstrated that gambling was associated with personality traits (impulsivity, sensation-seeking, self-control), risk attitudes, affect, and behavioural risk-taking consistent with previous research. In Study 4, it was demonstrated that measures of problem gambling have acceptable test-retest reliability. Online crowdsourcing platforms appear to offer access to samples with remarkably high proportions of problem gamblers. However, this characteristic means that such samples are not necessarily representative of gambling tendencies among more general populations.  相似文献   
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