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Coastal dunes provide a variety of cultural and ecological ecosystem services to local communities. However, most of these ecosystems are globally threatened by anthropic factors. Chile is home to important dune ecosystems such as the emblematic Ritoque coastal dunes located in the hotspot for biodiversity conservation in central Chile where there is a delicate relationship between conservation and human development interests, among local communities and authorities. Here, we performed a choice experiment study to determined willingness to implement conservation measures in the Ritoque dunes. In particular, we assessed residents’ preferences for improvements of the current state of local ecosystem services such as scenic beauty, biodiversity and archaeological sites. Residents showed preferences for improvements in Ritoque coastal dunes’ ecosystem services, and a high willingness to pay for protecting biodiversity and archeological sites, rather than for recreational infrastructure. Our study highlights the importance of place-based research that specifically addresses residents and stakeholders’ conservation priorities, which could be used to design and implement effective conservation management strategies for coastal ecosystems and coastal cities near them. 相似文献
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The random disposal of vegetable residues in north China has become an important obstacle for the sustainable development of vegetable industry. The composting treatment technology has been transformed into organic fertilizer by high temperature fermentation, which has become a widely promoted agricultural clean production technology. However, due to the voluntary nature of farmers' adoption and their reluctance to adopt, this study aimed at assessing the factors that influence their adoption will and evaluate the value of willingness to pay (WTP) for composting technology. Data were collected from 142 respondents through a household survey in Gaocheng District by using structural questionnaire of contingent valuation method (CVM). Some qualitative response models (Probit, Logistic and multiple linear regression models) were applied for examining the main factors influencing the vegetable residue compost adoption and estimating the WTP value. The findings showed that social resource factors play an important role in the respondents' behaviors toward composting technology adoption. The empirical results indeed highlighted that subsidy policy, top dressing time, age, scale, investment of irrigation and net income have significant positive influences on the WTP of compost, while work time and information sources have a negative impact. Government subsidy is a necessary premise for implementing the composting program. The governments should subsidize the remaining 97% of the construction costs to ensure the smooth implementation of composting technology. The findings specifically mentioned that the subsidy object should be the disadvantaged peasant groups with lower household income but more environmentally conscious. This paper is believed to not only assess the technical externality of vegetable residues for the first time but also provide decision reference for policymakers, especially in the background of rapid development of agricultural clean production technology, the accuracy and efficiency of subsidies should be improved. 相似文献
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According to property rights theory, national plant genetic resources (PGRs) are sovereign properties rather than resources belonging to the common heritage of humankind. Consequently, provider states can claim compensation from users of their national PGRs, leading to the need for bilateral or multilateral agreements to share national PGRs' commercial benefits. However, as benefit-sharing agreements are made exante, estimating the potential profit is difficult. Thus, issues around asymmetric information about the commercial value of such resources have emerged. In this paper, we use a patent portfolio as a proxy to estimate the potential commercial benefits of national PGRs and propose new evaluation indicators. We propose a comprehensive evaluation process that covers constructing a patent portfolio for each PGR, establishing indicators in terms of marketability, technology, and exclusiveness, and assigning weights to the indicators using fuzzy analytic hierarchy. In addition, we illustrate this process using a case of Korean national PGRs based on the opinions of stakeholders and experts. This research is expected to help promote national PGR transactions with equitable access and benefit sharing agreements. 相似文献
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R. Abgral P.-Y. Le RouxF. Blanc-Béguin T. EugèneS. Querellou C. Bodet-MilinF. Kraeber-Bodéré P.-Y. Salaün 《Médecine Nucléaire》2011,35(11):600-607
18Fluoro-deoxyglucose (FDG) positron emission tomography (PET) is an imaging technique which studies the cellular glucidic metabolism. It is particularly indicated in oncology, especially for cancer diagnosis (with a potential prognosis interest) or detection of recurrence. Because of its functional approach to the tissues, its use has logically evolved into the evaluation of cancer treatments, both for the individual care of patients for clinical trials of new therapies. Also, it tends to displace conventional imaging in this indication, whose main limitation is not to assess the viability of residual masses, potentially necrotic or fibrous after treatment. However, the use of FDG-PET requires a rigorous methodology for both the exams achievement but also for the quality of their interpretation, including the choice of the comparison tool. Based on an increasing literature on the subject, were published and updated interpretation criteria for both lymphoma and solid cancers. For lymphoma, standardized assessment criteria were proposed in 2007 during an International Harmonize Project (IHP). For solid cancers, Positron Emission tomography Response Criteria In Solid Tumors (PERCIST) recommendations version 1.0 were recently proposed by an American workshop in 2009 in order to clarify and standardize practices. 相似文献
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R. Almeida S. E. Tanner C. S. Mateus F. Ribeiro B. R. Quintella 《Journal of fish biology》2024,104(4):1241-1246
European sea bass (Dicentrarchus labrax [Linnaeus, 1758]) is a euryhaline marine migrant fish highly valuable for fisheries and aquaculture. Although juveniles are known to use estuaries and occasionally move to freshwater environments, these freshwater incursions had not been reported for adults. Recently, this behavior was observed in the Tagus River (Portugal) for adults occurring up to 150 km from the river mouth, about 80 km upstream from the tidal influence, suggesting the existence of a freshwater contingent. Fisheries management of sea bass should consider the putative existence of a freshwater contingent. 相似文献