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Percutaneous osseointegrated implant technology provides a potential alternative to current socket prosthetics for individuals with limb loss. However, similar to other percutaneous devices, there remain concerns of periprosthetic infection. To understand this process of infection, bacterial isolates were collected and characterized from a sheep model of osseointegration. CSA-13, a novel cationic steroid antimicrobial, was used at the skin/implant interface in an attempt to reduce the rate of infection. Results indicated that in this application, normal flora and environmental organisms continued to colonize the skin/implant interface as well as cause infection in the presence of CSA-13. Two factors are believed to have contributed to this outcome: the delivery of CSA-13 and the lack of a skin seal at the skin/implant interface, which would create a biological barrier to infection.  相似文献   
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Tobacco smoking, betel quid chewing and alcohol drinking are oral cancer risk factors. Observational studies unanimously report that oral cancer risk in smoking-drinking-chewing exposed subjects is exceptionally high. However, none of them assessed the fractions of this risk attributable to the three individual risk factors and to the smoking-drinking-chewing interaction. The present study sought to assess the magnitude of the smoking-drinking-chewing interaction effect on oral cancer. A meta-analysis of observational South-East Asian studies which reported oral cancer odds ratios (ORs) stratified for smoking-drinking-chewing exposures was performed. The pooled ORs were estimated and controlled for quality, heterogeneity, publication bias and inclusion criteria. The smoking-drinking-chewing interaction effect was estimated through the pooled Relative Excess Risk due to Interaction (RERI, excess risk in smoking-drinking-chewing exposed individuals with respect to the risk expected from the addition of the three individual risks of smoking, drinking and chewing). Fourteen studies were included with low between-study heterogeneity. The pooled ORs for smoking, drinking, chewing, smoking-drinking-chewing, respectively were 3.6 (95% confidence interval −95% CI, 1.9–7.0), 2.2 (95% CI, 1.6–3.0), 7.9 (95% CI, 6.7–9.3), 40.1 (95% CI, 35.1–45.8). The pooled RERI was 28.4 (95% CI, 22.9–33.7). Among smoking-drinking-chewing subjects, the individual effects accounted for 6.7% (smoking), 3.1% (drinking), 17.7% (chewing) of the risk, while the interaction effect accounted for the remaining 72.6%. These data suggest that 44,200 oral cancer cases in South-East Asia annually occur among smoking-drinking-chewing exposed subjects and 40,400 of these are exclusively associated with the interaction effect. Effective oral cancer control policies must consider concurrent tobacco smoking, alcohol drinking, betel quid chewing usages as a unique unhealthy lifestyle.  相似文献   
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In the adult African clawed frog, Xenopus laevis, olfactory epithelium is housed in three separate nasal cavities: the principal cavity, the middle cavity, and the vomeronasal organ. The sensory epithelium in each of these cavities has distinct cellular features, and presumed physiological and behavioral functions, which arise during metamorphosis. Most notably, the middle cavity is formed de novo, and the principal cavity is transformed from a larval sensory epithelium with water exposure to an adult olfactory epithelium with air exposure. To understand the cellular nature of this plasticity more clearly, we characterized the staining patterns generated in the olfactory system of X. laevis with a new monoclonal antibody, anti-E7. The olfactory epithelium is first stained with anti-E7 during late embryonic development. Transection of the olfactory nerves during metamorphosis eliminates all staining and indicates that the staining is associated with mature or nearly mature olfactory receptor neurons. The antibody diffusely stains the vomeronasal organ throughout development and in adults. In the larval principal cavity, the olfactory receptor neurons are brightly stained, but this cellular staining is lost after metamorphosis. The mucus from Bowman's glands in the principal cavity, however, is intensely stained in adults. The middle cavity, throughout development and in adulthood, has the same staining characteristics as the larval principal cavity. Thus, the E7 antibody can distinguish the three areas of the olfactory epithelium, allowing measurement of sensory epithelium volume, and serves as an excellent marker for the changes in the sensory epithelium that occur during metamorphosis.  相似文献   
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Purpose

Social life cycle assessment (SLCA) is a methodology under continuous development, which may be applied at different scales: from products to economic sectors up to systems at region (meso) and country (macro) scales. Traditionally, SLCA has been focusing on the assessment of negative social externalities, whereas also positive social impacts could be associated to human interventions. The purpose of the present study is to understand how positive impacts are defined in published literature and how they could be assessed through indicators. The aim is to clarify the concept among scholars and to support decision making in business and policy context.

Methods

The study uses a systematic review approach in order to analyse the types of indicators adopted. In the field of SLCA and according to Paragahawewa et al. (2009), “[I]ndicators are ‘pointers’ to the state of the impact categories (and/or subcategories) being evaluated by the SLCA”. Indicators can be quantitative, semi-quantitative or qualitative (UNEP/SETAC 2009). This review was carried out in order to identify and analyse positive impacts and indicators. After careful scrutiny, 47 papers containing theoretical frameworks were considered, as well as 46 papers presenting case studies.

Results and discussion

Compared to environmental life cycle assessment (E-LCA), where the presence of positive impacts is lower, evaluating benefits or positive impacts can still play a major role in SLCA (Benoît et al. 2010). A quarter of the analysed papers on theoretical frameworks take into account the topic of positive impacts and indicators. Results from case study analysis highlight as “workers”, was the most considered stakeholder (in 100 % of the analysed papers), and as the majority of positive indicators used in the case study analysed are recorded in relation to “other value chain actors”. Within the concept of “positive impacts”, no reference should be made merely to the utility of a product or service. In a broader sense, we could refer to solutions improving the conditions of one or various stakeholders involved. In other words, these are solutions that carry a positive contribution to one or more stakeholders without harming others.

Conclusions

So far, positive impacts are barely covered in literature. There is a clear need of streamlining definition and indicators, especially if they should be applied in a policy context complementing traditional—and often monetary-based, cost-benefit analysis (CBA).
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