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111.
A desirable function for terrestrial urban ecosystems is the mitigation of nitrogen (N) pollution associated with cities and suburbs. To assist in maximizing this function, identifying locations of sources and sinks of N in the urban environment is crucial to inform management strategies. Lawns are an extensive land cover in urbanized landscapes, and in general, they have demonstrated the capacity to function as a sink for N inputs. How N is cycled by lawns, however, is likely not uniform across the physical heterogeneity or management activities that exist in lawns. We investigated the influence of heterogeneity in light availability on N cycling in lawns that were irrigated but not fertilized. Light availability is affected by tree canopy and built structures and is, therefore, heterogeneous both within individual lawns and among lawns. Light is expected to control N retention and loss through effects on primary productivity. We experimentally examined N regulation over one calendar year by measuring net primary production (NPP), N retention using an isotopic tracer, and N leaching in existing unfertilized lawns under heterogeneous light conditions. We used a budgetary approach to estimate gaseous N loss which we assume is primarily via denitrification. Light functioned as a limiting resource for primary productivity. From low to high light conditions, annual NPP increased 177 to 430 g C?m?2?y?1 and retention of N isotope tracer increased from 50 to 65% as a result of increased retention in plants. Nitrate leaching losses were low overall and were not affected by light levels. Light availability regulated the fate of N inputs and unfertilized lawns may function as substantial sinks for reactive N through storage in the terrestrial system and N loss by denitrification. However, whether or not denitrification is generally an N sink will depend on the ratio of non-reactive (i.e., N2) to reactive (i.e., N2O, NO) denitrification products. Overall, we find that effective strategies for managing N sources and sinks in cities will likely need to consider light availability, particularly in systems receiving water subsidies via irrigation.  相似文献   
112.
The role of urban expansion on bee diversity is poorly understood, but it may play an important role in restructuring pollinator diversity observed in rural regions at the urban perimeter. We studied bee communities in two habitats essential for pollinators (residential gardens and semi-natural areas) at 42 sites situated at the edge of greater Montreal, Canada. Bee species richness, abundance and functional diversity all increased with urbanization in both habitat types, but gardens and semi-natural areas supported distinct bee communities with unique responses to urbanization in terms of species turnover. Compared to semi-natural sites, residential gardens supported bees that foraged from a greater number but a lower proportion of available plant species. Bees did not discriminate between exotic and indigenous plant species in either gardens or semi-natural sites and were attracted to flowers in either habitat irrespective of their origins. Protecting semi-natural ruderal areas and providing residential garden habitats for pollinators are both effective means of promoting regional bee diversity in urbanizing regions.  相似文献   
113.
A lack of adequate childcare can delay mothers’ return to the labor market after childbirth. This paper examines whether social support with childcare by kin and friends facilitates maternal employment in the first 72 months after childbirth. Using data from the German Socio-Economic Panel (SOEP) 1993–2009, a comparison of natives (n?=?1409) and migrants (n?=?411) in corporative-conservative western Germany with mothers in former socialist eastern Germany (n?=?528) shows that kinship support is positively associated with maternal employment when public childcare is limited. Western German and migrant mothers return to work sooner if they are surrounded by kin. But kin do not provide support for maternal employment in eastern Germany, where public childcare is more easily accessible and continuous female employment is a prevalent social norm. Friendship networks, by contrast, are most valuable for maternal employment if they complement public childcare.  相似文献   
114.
This article explains Internet users’ self-help activities in protecting their privacy online using structural equation modeling. Based on a representative survey of Swiss Internet users, it reveals past experiences with privacy breaches as a strong predictor of current protective behavior. Further, in line with the ‘privacy paradox’ argument, caring about privacy (privacy attitudes) alone does not necessarily result in substantial self-protection. Most strikingly, however, general Internet skills are key in explaining users’ privacy behavior. These skills enable users to reduce risks of privacy loss while obtaining the benefits from online activities that increasingly depend on the revelation of personal data. Consequently, Internet skills are an essential starting point for public policies regarding users’ self-help in privacy protection.  相似文献   
115.
Contemporary managers are developing alternative ways to sustain their competitive advantages. Motivation-enhancing features such as high-quality meal service provided by organizations can be thought of as one of these methods. The effect of the perceived quality of meal service provided by organizations on the job performance of employees and the mediating role of organizational identification during this process is studied. Private security-sector employees working in Turkey (N?=?597) are being focused in this study. As a result of analyses (correlation and regression analyses, structural equation model), the authors find that the perceived quality of meal service provided by organizations improves employees’ job performance significantly and organizational identification has a partial mediating role on this association. The findings of this study will be of interest to key stakeholders such as public or private organizations, labor unions and the media.  相似文献   
116.
In explicit persuasion, the communicator states explicitly a desire to persuade the consumer. By referring to an attributional approach, social engagement was simultaneously explored as a beneficial communicator attribute, while cause-related marketing (CRM) was addressed as a boundary condition. In an experiment, we varied the persuasion strategy (explicit vs. implicit), the communicator’s prior experience with social engagement (yes vs. no), and the specific marketing strategy (CRM vs. non-charity marketing). As expected, in the non-charity marketing condition, explicit (vs. implicit) persuasion was more effective when the communicator had prior experience in social engagement. In the CRM condition, explicit (vs. implicit) persuasion was less effective when the communicator had prior experience in social engagement; when no prior experience was reported, persuasiveness increased.  相似文献   
117.
One of the most prevalent problems in face transplant patients is an inability to generate facial expression of emotions. The purpose of this study was to measure the subjective recognition of patients’ emotional expressions by other people. We examined facial expression of six emotions in two facial transplant patients (patient A = partial, patient B = full) and one healthy control using video clips to evoke emotions. We recorded target subjects’ facial expressions with a video camera while they were watching the clips. These were then shown to a panel of 130 viewers and rated in terms of degree of emotional expressiveness on a 7-point Likert scale. The scores for emotional expressiveness were higher for the healthy control than they were for patients A and B, and these varied as a function of emotion. The most recognizable emotion was happiness. The least recognizable emotions in Patient A were fear, surprise, and anger. The expressions of Patient B scored lower than those of Patient A and the healthy control. The findings show that partial and full-face transplant patients may have difficulties in generating facial expression of emotions even if they can feel those emotions, and different parts of the face seem to play critical roles in different emotional expressions.  相似文献   
118.
Human rights (HR), from the perspective of interest and thematic selection, are recognized in the topics of the communication. In general, there is considered to be a positive relationship between the media and its function of mediation with citizenship in reference to the declared general principles since inception in 1948. With this approach, the paper deals with providing an updated reflection of that connection and its main difficulties, such as the crisis of credibility in the information in the context of the European Union and within the framework of the paradigm changes that has derived in the knowledge society of the so-called third environment. The precepts of those recognized as generations of HR survive in the informational stories, of which, due to their current relevance in recent decades, those related to migratory movements, inequality, and poverty stands out. Moreover, the paper explores and discusses how a new generation derived from the implementation and intervention of technology gets involved as an essential characteristic in the relations between the members of society.  相似文献   
119.
Food and nutrition insecurity remains a challenge in sub-Saharan Africa. Several studies have examined food and nutrition insecurity in urban or rural areas but have not captured the whole continuum. Between November and December 2013, 240 households were surveyed along the urban–rural continuum in Northern Ghana. The study objective was to understand the socio-spatial dynamics of household food and nutrition insecurity and to investigate the role played by urban, peri-urban and rural agriculture. The study found that there was more involvement in agriculture in rural areas compared to peri-urban areas and urban areas. Households from urban areas were more food insecure (HFIAS >?11) compared to their counterparts in peri-urban and the rural areas. Stunting increased by 3.4 times (p?=?0.048) among households located in the peri-urban area. Wasting was reduced by 0.16 times among household that produced staple food or vegetables (p?=?0.011). Overweight was reduced by 0.04 times among households that produced livestock (p?=?0.031). The results reveal a socio-spatial dimension of food and nutrition insecurity that is related to agricultural activities.  相似文献   
120.
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