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1.
《Ecological Indicators》2008,8(2):115-122
Criteria and indicators (C&I) have emerged as a powerful tool in implementing sustainable forest management. In a relatively short period, around 150 countries have adopted C&I. Some processes have used C&I in forest management and produced progress reports. Six of the seven thematic areas common to all processes are also being used as a basis for reporting progress towards sustainable forest management [e.g., the Food and Agriculture Organization of the United Nations (FAO) in its Global Forest Resource Assessment 2005]. However, there are significant problems in the wider application of C&I. A number of countries are not using C&I at all, and in some countries where they are being used, it is not done in an effective manner. Areas that need improvement in order to promote the use of C&I include: (1) strengthening concepts and definitions; (2) rationalising criteria and indicators; (3) further research on indicators; and (4) utilising C&I in more effective ways. The future development of C&I must be based on an active link between research effort and operational needs in order to prevent a waste of resources and effort. Some of the research undertaken to date has led to the adoption of innovative approaches to optimise resource use and simplify application. This paper identifies areas needing more research and draws from ongoing work to show where progress is being made.  相似文献   

2.
Monoclonal antibody therapy of chronic lymphocytic leukemia   总被引:3,自引:0,他引:3  
Cure of patients with chronic lymphocytic leukemia (CLL) has been an elusive goal. The recent availability of active monoclonal antibodies has rekindled enthusiasm for new and innovative therapeutic approaches. Alemtuzumab, induces responses in about a third of patients with relapsed or refractory CLL following therapy with fludarabine and an alkylating agent. Whereas, rituximab has limited activity in previously treated patients, response rates of 50-70% have been reported in those without prior therapy. Recent data on combinations with rituximab and chemotherapy have shown promise for improving patient outcome. Newer antibodies in development include the primatized monoclonal antibody lumiliximab (IDEC-152), directed against CD23. Other biological approaches include the use of antisense oligonucleotides, proapoptic small molecules, and vaccines directed against the malignant B cells. The rational development of combinations of these promising approaches may eliminate the need for chemotherapy, leading to safer and more effective approaches for patients with CLL.  相似文献   

3.
Many species in the family Pinaceae are invaders. These species are relatively easy to control because of some of their intrinsic characteristics and because they are highly visible and easy to eliminate. Many Pinaceae species have been well studied because of their use in forestry and their invasive behavior in many countries. The impacts of invasive Pinaceae are not only ecological, but also economic and social. We review the ecology and management of Pinaceae invasions and explore how restoration of invaded areas should be addressed. There are many ways to prevent invasions and to deal with them. Planting less invasive species, better site selection, and invasion monitoring are used successfully in different parts of the world to prevent invasion. Mechanical and chemical methods are used effectively to control Pinaceae invasions. Control is more effective at the early stages of invasion. Old invasions are more problematic as their elimination is more expensive, and the restoration of native vegetation is challenging. In some areas, native vegetation cannot thrive after Pinaceae have been removed, and weeds colonize cleared areas. More attention is needed to prevent the initiation and spread of invasions by focusing control interventions at early stages of invasion. Finding new ways of dealing sustainably with conflicts of interest between foresters and conservationists is crucial. Non-native Pinaceae are important parts of the economies and landscapes in several countries and they will continue to play such a role in the future. Despite the numerous challenges facing Pinaceae invasion management, several approaches can be successful at controlling them. Proper application of current techniques and development of more efficient ones is needed if the goal of maximizing benefits and minimizing negative impacts is to be achieved.  相似文献   

4.

Pest management on a global scale experienced a total revolution after World War II when synthetic organic compounds were in agriculture and public health. However, it soon became apparent that there were many limitations in the use of chemicals for pest management. In agriculture, problems of pest resurgence, secondary pest outbreaks, pest resistance and adverse effects of pesticides on the environment, including human poisoning and toxicity to other non-target organisms, led to the search for alternative approaches to the pest outbreak problem. The 1960s produced new ideas on integrated pest management (IPM) strategies, followed by intensification of the search for biological control agents, which could be incorporated into IPM programmes. New application technologies were developed in the 1970s and 1980s and ecological approaches to the pest problem were spearheaded in the developed world in the 1990s, with extensive studies focused on the whole ecosystem. Important advances in crop production have also taken place in Africa in this century, involving adoption of high yielding varieties, fertilizer application, intensification of crop protection approaches, less shifting cultivation and more mono-cropping systems. However, these advances have led to increasing pest problems which unless tackled imaginatively and intelligently, they could become the most important constraint in crop production in the present millennium. Africa has entered the current millennium with relatively underdeveloped agriculture on a global scale and little investment in research on new pest management technologies that could be used to reduce crop losses. We are still highly dependent on pesticides for pest management. Therefore, the greatest challenges in agriculture in Africa will be the switch from a pesticide based mode of reducing losses due to pests to one that is ecosystem based, making use of insect management techniques which are ecologically and economically sound. Specifically, some of the major challenges in pest management in agriculture in Africa include; (i) reducing the dependence on pesticides, thus avoiding the limitations observed in the past 50 years; (ii) overcoming ignorance of the pest species and their associated community of parasites and predators which has dire consequences on the whole ecosystem; (iii) keeping out exotic pests, which in this millennium have had a devastating blow on the production of some crops and (iv) developing indigenous technologies for pest management (IPM, biocontrol, etc.) and making available to farmers materials for pest management which are affordable, safe, effective and environmentally friendly (e.g. microbial, botanicals, pheromones, genetically engineered products etc.). Both legislative and quarantine measures will have a significant role to play in pest management in the next millennium, but only when practised on a wider geographical area. Information technology (IT) will affect the way we acquire and make use of pest management strategies. Africa is therefore faced with the challenge of building up and improving its infrastructure and expertise on IT if it is to benefit pest management on the continent.  相似文献   

5.
The effective treatment of life-threatening ventricular arrhythmias (VA) leading to sudden cardiac death remains a major health problem. Cellular electrophysiological techniques that have provided insight into the underlying mechanisms of these arrhythmias have also provided a convenient classification of antiarrhythmic drugs based on their dominant electrophysiological action. Traditional pharmacological approaches to the management of VA have involved primarily class I agents. Newer drugs in this class are potent conduction depressants (class IC agents), which, however, have been limited in their clinical impact on VA because of unwanted cardiac and extracardiac side effects. Other recent approaches include the introduction of class III agents, which are thought to interrupt primarily reentrant impulses by specific prolongation of action potential duration and refractoriness without compromising normal cardiac conduction. Newer approaches may also include drugs with greater specificity of action, agents with combinations of electrophysiological effects (class I/III, I/II), drugs exemplifying novel mechanisms of action such as anion antagonism (class V), and agents controlling sympathetic neural outflow. The growing awareness of the potential proarrhythmic effects of antiarrhythmic drugs has also become important in drug development and assessment, as emphasized by the search for improved methods of drug selection (e.g., programmed electrical stimulation). Finally, the desired characteristics of a new antiarrhythmic agent are presented as a goal for future drug development.  相似文献   

6.
中国生物多样性就地保护的研究与实践   总被引:9,自引:0,他引:9  
马建章  戎可  程鲲 《生物多样性》2012,20(5):551-558
中国是世界上生物多样性最丰富的地区之一,但面临着较大的生态衰退风险。中国生物多样性受到的威胁来自包括人口众多、经济发展模式单一落后、工业化进程加快、气候变化和外来物种入侵等多种因素。生物多样性的就地保护对于维护国家生态安全具有重要意义,同时也是中国可持续发展的需要。本文就中国生物多样性就地保护的研究成果和保护成就进行了回顾,提出了未来应该着重加强的研究领域。中国生物多样性的就地保护研究与实践主要集中在生物多样性资源调查、濒危物种管理和自然保护区建设等方面。中国政府在生物多样性就地保护领域开展了大量卓有成效的工作,发布实施了一系列的保护行动规划,不断提高了生物多样性的保护水平。中国的生物多样性就地保护经过了由数量发展到质量发展的阶段后,未来的研究重点应该集中在生物多样性形成与维持机制、生物多样性受胁原因与响应机制、生物多样性长期监测与评估、自然保护区有效管理和自然保护区立法等方面。  相似文献   

7.
Idowu et al., in this edition of Plant and Soil describe a welcome new tool that allows farmers to optimize the management of their fields. It is based on a holistic approach that integrates assays of soil physical, chemical and biological parameters into an easily understandable, low-cost and quantitative estimate of soil quality or “health”. It can facilitate tracking and understanding of the short and long term effects of different management approaches on soil (and crop) health. Most of the assays used are based on traditional, labour-intensive techniques. The tool could be improved through employment of assay technologies that are under development. For example, Idowu et al., in this edition investigated the use of near infra-red spectroscopy as a replacement for some of the traditional soil assays. Similarly, future developments in remote spectroscopic assays, using satellite, airborne or land-based platforms may facilitate further improvement.  相似文献   

8.
In recent decades, the world has witnessed an array of harmful invasions by exotic marine organisms. To provide the public and policymakers with better information on the status of exotic species in southern California waters, and to assess differences between port and non-port areas, a Rapid Assessment Survey of selected habitat types in sheltered waters between San Diego and Oxnard was conducted in the summer of 2000. The objectives included comparing the prevalence of exotic species among habitats and regions and between recent and past surveys; obtaining reference data for future assessments of changes in invasion status and the effectiveness of prevention or control efforts; detecting new invasions; and documenting significant range extensions. Twenty-two sites were sampled to include the three major commercial port areas in southern California, non-port-area marinas and lagoon sites. Sampling included dock fouling and adjacent soft-bottom benthos, nearby intertidal sites, and selected subtidal lagoon habitats. Samples were collected by a variety of manual techniques. Sixty-nine of the species collected are exotic, including representatives from two algal divisions and six invertebrate phyla. Ascidians are especially well-represented (14 exotic species) and widely occurring, and some bivalves and bryozoans also occur very widely. The numbers and proportions of exotic taxa were not significantly greater in port areas than in non-port areas.  相似文献   

9.
Abstract Protozoan parasites are important animal and human pathogens. At present, most of these infections are controlled by chemotherapy. In addition, vaccines are available for some of these diseases. There is, however, still an urgent need for the development of vaccines against protozoal diseases, since the current array of available vaccines is very limited. This review describes the different approaches that have been taken to develop such vaccines and discusses the difficulties that hampered vaccine development. Many of the problems are related to the complex life cycle of these parasites and the virtual lack of mass in vitro culture systems. We also give an overview of the commercial and non-commercial vaccines that do exist at present. Finally, we describe the future directions of this interesting field. New techniques and strategies include parasite cultivation methods and recombinant-DNA techniques, such as vector vaccines and DNA-vaccines. Moreover, these approaches are complemented by the development of sophisticated adjuvants; the coupling of immunoprotective molecules to entities with adjuvant activity or the use of cytokines, e.g. IL-12. Through these innovations new vaccines against protozoal diseases will become available in the near future.  相似文献   

10.
A vaccine against Asian schistosomiasis   总被引:13,自引:0,他引:13  
There is continued transmission of schistosomiasis japonica in China and Philippines despite highly effective control programs that focus on the application of the highly effective drug praziquantel (PZQ). The massive Three Gorges Dam across the Yangtze River in Southern China, soon to be completed, is expected to significantly increase schistosomiasis transmission and introduce the disease into areas currently unaffected. After long-term experience it is generally accepted that PZQ chemotherapy, although the cornerstone of current control programs, does have significant limitations. Furthermore, efficient drug delivery requires a substantial infrastructure to regularly cover all parts of an endemic area. Although there is not yet clear-cut evidence for the existence of PZQ-resistant schistosome strains, decreased susceptibility to the drug has been observed in several countries. As a result, a protective vaccine represents an essential component for the long-term control of schistosomiasis. This article briefly reviews aspects of anti-schistosome protective immunity that are important in the context of vaccine development. The current status in the development of vaccines against Schistosoma japonicum will then be discussed as will new approaches that may improve on the efficacy of available vaccines, and aid in the identification of new targets for immune attack. With new and extensive data becoming available from the S. japonicum genome project, the prospects for developing an effective vaccine are encouraging. The challenges that remain are many but it is crucial that the momentum towards developing effective anti-schistosome vaccines is maintained.  相似文献   

11.
The use of geographical information systems (GIS) in the management of African animal trypanosomosis in sub-Saharan Africa offers potential in assisting decisions on allocation of resources, prioritization of control areas, and planning and management of field operations. Here, Guy Hendrickx and colleagues review approaches being used to develop reliable data-layers and to incorporate these data into GIS models. They argue that techniques should be further refined to produce more-detailed data layers and to include a dynamic element, a problem rarely addressed until now.  相似文献   

12.
Dengue viral infection has become an increasing global health concern with over two-fifths of the world's population at risk of infection. It is the most rapidly spreading vector borne disease, attributed to changing demographics, urbanization, environment, and global travel. It continues to be a threat in over 100 tropical and sub-tropical countries, affecting predominantly children. Dengue also carries a hefty financial burden on the health care systems in affected areas, as those infected seek care for their symptoms. The search for a suitable vaccine for dengue has been ongoing for the last sixty years, yet any effective treatment or vaccine remains elusive. A vaccine must be protective for all four serotypes of dengue and be cost-effective. Many approaches to developing candidate vaccines have been employed. The candidates include live attenuated tetravalent vaccines, chimeric tetravalent vaccines based on attenuated dengue virus or Yellow Fever 17D, and recombinant DNA vaccines based on flavivirus and non-flavivirus vectors. This review outlines the challenges involved in dengue vaccine development and presents the current stages of proposed vaccine candidate development.  相似文献   

13.
Ongoing efforts over the last 50 years, aiming at the elimination of schistosomiasis in the People's Republic of China, have been spectaculary successful in reducing the prevalence and intensity of the infection. The endemic areas have been reduced to core regions with particular problems such as the middle and lower reaches of the Changjiang River (Yangtze), the land adjacent to the lakes of central China and certain mountainous areas in Sichuan and Yunnan. An effort to eradicate schistosomiasis as a public health problem in these areas, by means of mass chemotherapy in regions of high prevalence and selective chemotherapy in others, provided good results initially but a lasting effect proved unattainable with chemotherapy alone. A small part of the funds available for this effort were used for research and training. Overseen by a Joint Research Management Committee (JRMC), research training was intensified resulting in improved applications and a better quality of the scientific level of the research finally carried out. Several new control tools were produced which may improve future control approaches, which might achieve a more than temporary relief. In evaluating the contributions made, it was found that the great environmental variations between the eight provinces where control activities were implemented was the main reason why general use of chemotherapy only could not be entirely successful. The inclusion of a research component proved beneficial both for the short- and long-term control and the JRMC proved useful in exposing that sustained progress cannot be achieved without back-up by other approaches, e.g. snail control. Suggested future activities include strengthening of intersectoral and industrial collaboration but finding financial support for continuing the JRMC initiative in some form. It is crucial to consolidate progress made.  相似文献   

14.
The use of proteomic approaches in investigating diseases is continuing to expand and has started to provide answers to substantial gaps in our understanding of disease pathogenesis as well as in the development of effective strategies for the early diagnosis and treatment of diseases. Biophysical techniques form a crucial part of the advanced proteomic techniques currently used and include mass spectrometry and protein separation techniques, such as two-dimensional gel electrophoresis and liquid chromatography. The application of biophysical proteomic techniques in the study of disease includes delineation of altered protein expression, not only at the whole-cell or tissue levels, but also in subcellular structures, protein complexes, and biological fluids. These techniques are also being used for the discovery of novel disease biomarkers, exploration of the pathogenesis of diseases, development of new diagnostic methodologies, and identification of new targets for therapeutics. Proteomic techniques also have the potential for accelerating drug development through more effective strategies for evaluating a specific drug’s therapeutic effects and toxicity. This article discusses the application of biophysical proteomic techniques in delineating cardiovascular disease and other diseases, as well as the limitations and future research directions required for these techniques to gain greater acceptance and have a larger impact.  相似文献   

15.
When restoring ecosystems dominated by exotic plants, reinvasion pressure, or the rate of new exotic recruitment following mature exotic removal, can vary broadly between similarly invaded habitats. Reinvasion pressure strongly influences restoration costs and outcomes but is difficult to predict. Ontogenetic niche shifts (ONSs, changes in niche breadth or position during development) in exotic species paired with interannual variation in abiotic conditions may decouple pre‐removal mature exotic density and average reinvasion pressure. Identifying such decouplings could improve restoration efficiency by informing site selection and management strategies, but requires estimates of average reinvasion pressure that mandate greater understanding of its principle drivers. We hypothesize that reinvasion pressure is predominantly driven by exotic propagule abundance and spatiotemporal availability of realized recruitment windows, which are periods of variable duration that permit exotic establishment from propagules. Realized recruitment windows are based on the “safe sites” concept but account for ONSs and are determined by abiotic conditions and interspecific interactions with recipient communities. Biotic resistance or facilitation may increase or decrease times required for establishment by influencing exotic growth rates or altering niche availability and may permit or preclude establishment in marginal abiotic conditions. We discuss factors influencing reinvasion pressure, basic approaches to estimate reinvasion pressure, and potential ways to increase management efficiency under different reinvasion pressure scenarios. Accurate estimates of reinvasion pressure could improve restoration efficacy, efficiency, and predictability in ecosystems dominated by exotic plants. We argue that greater theoretical and practical considerations of reinvasion pressure and ONSs are merited.  相似文献   

16.
In spite of the numerous efforts made to control their transmission, parasite schistosomes still represent a serious public health concern and a major economic problem in many developing countries. Praziquantel (PZQ) is the drug of choice for the treatment of schistosomiasis and the only one that is available for mass chemotherapy. However, its widespread use and its inefficacy on juvenile parasites raise fears that schistosomes will develop drug resistance, and make the development of alternative drugs highly desirable. Protein tyrosine kinases (PTKs) are key molecules that control cell differentiation and proliferation and they already represent important targets for molecular cancer therapy. The recent characterization in Schistosoma mansoni of several cytosolic and receptor PTKs, with properties similar but also divergent from their vertebrate counterparts, opens new perspectives for the development of novel strategies in chemotherapy of schistosomiasis, which could be based on the use of parasite-specific tyrosine phosphorylation inhibitors.  相似文献   

17.
随着世界经济的发展和全球经济一体化进程的加快,外来物种入侵已成为影响国家安全的主要因素之一。我国外来入侵物种数量繁多,已成为遭受外来生物危害最严重的国家之一,入侵物种已对我国生态系统、环境和社会经济造成了严重的影响。近年来,各国都积极采取措施,制定外来物种入侵管理政策,加强外来物种入侵立法,确保国家及国际生物安全。然而,我国现有的针对外来物种的相关法律法规存在明显滞后。本文综述了我国外来物种入侵的现状及相关立法,指出外来物种入侵可在不同生态系之间发生,揭示了行政区划与生态系差异造成外来物种入侵管理存在"自然与经济的错位"、国内管理方面存在"生态系统与行政区域的错位"的"双错位现象",分析了我国外来物种的管理现状及今后的发展方向,以期探求我国在国际背景下的外来物种管理对策,提出制定《外来入侵物种法》及相关法律的国家体系、建立跨部门协作科学研究体系以及建设行政管理体系,增强抵御外来物种入侵的能力,实施以防为主的管理策略。  相似文献   

18.
19.
Ecosystem Approaches to Health for a Global Sustainability Agenda   总被引:1,自引:0,他引:1  
International research agendas are placing greater emphasis on the need for more sustainable development to achieve gains in global health. Research using ecosystem approaches to health, and the wider field of ecohealth, contribute to this goal, by addressing health in the context of inter-linked social and ecological systems. We review recent contributions to conceptual development of ecosystem approaches to health, with insights from their application in international development research. Various similar frameworks have emerged to apply the approach. Most predicate integration across disciplines and sectors, stakeholder participation, and an articulation of sustainability and equity to achieve relevant actions for change. Drawing on several frameworks and on case studies, a model process for application of ecosystem approaches is proposed, consisting of an iterative cycles of participatory study design, knowledge generation, intervention, and systematization of knowledge. The benefits of the research approach include innovations that improve health, evidence-based policies that reduce health risks; empowerment of marginalized groups through knowledge gained, and more effective engagement of decision makers. With improved tools to describe environmental and economic dimensions, and explicit strategies for scaling-up the use and application of research results, the field of ecohealth will help integrate both improved health and sustainability into the development agenda.  相似文献   

20.
Restoring urban forests often involves eradicating exotic species and diligently guarding against future invasions. Understanding how landscape structure contributes to the distribution of exotic species may inform these management efforts. To date, the distribution of exotic species in forested patches has been correlated with the type of development surrounding the patch, with those surrounded by agricultural or urban development often more highly invaded. Yet, previous studies have categorized land use types and have not examined more local-scale changes in land use. These local changes may be particularly important in urban areas where forested patches are immediately surrounded by diverse land use types. Our study examined how two key aspects of landscape structure, patch size and adjacent land use, may influence patterns of exotic species invasion of riparian buffers within Raleigh and Cary, North Carolina, United States. We found that large patch size alone, in our case, wide riparian buffers, does not protect against exotic species invasion. Patches surrounded by higher canopy-cover landscapes (e.g., forests and older residential developments with mature canopy) were more likely to be invaded than those surrounded by less canopy cover (e.g., shopping malls and other commercial development). We attribute these results, in part, to increased pressure from exotic propagules from adjacent forests. When restoring urban forests, attention should be paid to local land use to better plan for successful, long-term eradication of exotic species.  相似文献   

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