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方伟伟  于顺利 《生态学杂志》2013,32(8):2238-2244
总结了果实生态学的概念及主要研究内容,对国内外的果实生态学研究领域的进展进行了综述,分析了这些研究尚存在的不足之处,并指出了未来研究的科学问题.迄今为止,果实生态学在果实与种子的关系、果实颜色与环境、果实化学成分与环境、群落果实构成式样的地理分布特征、果实及食果动物的协同进化等方面已经取得了若干进展.果实重量谱等物理性状的空间分异格局及机理、果实化学成分的时空变异格局、果实类型的组成式样及大尺度地理分布格局及其机制的探讨、果实传播与食果动物的协同进化等是未来亟待开展的工作.  相似文献   

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Exploitation and exploration of the Amazon basin by Europeans started in the 17th century, but only since about 1970 has the Brazilian government given priority to the connection of the Amazon basin to the industrialized southern part of the country. This new policy required scientific research on the natural resources of the area. Wetlands cover about 20% of the Amazon basin. Inland fishery, fertile floodplain soils, and hydroelectric energy offer a large potential for economic development. Research concentrates on major wetlands and water bodies near the large cities. The Amazon River floodplain belongs to the best studied tropical river floodplains in the world. However, studies in other areas suffer from lack of wetland inventory and classification. Accelerated economic development is not adequately accompanied by wetland research. Insufficient knowledge about distribution, size, structure and function of many wetlands leads to increasing degradation and loss of biodiversity, for instance, by the construction of hydroelectric power plants, large scale deforestation for cattle ranching and agro-industrial projects, mining activities, the construction of navigation channels (hidrovias), etc. The low number of scientists working in the area and lack of funding require close cooperation in problem-oriented multidisciplinary projects (scientific clustering) to optimize scientific outcome. Intensive, long-term cooperation and scientific exchange with institutions from southern Brazil and from abroad is recommended to improve the scientific infrastructure in Amazonian institutions, to accelerate the transfer of new scientific methods and technology, and to intensify the training program for local human resources.This revised version was published online in March 2005 with corrections to the issue cover date.  相似文献   

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B Lyons 《Bioethics》2012,26(7):369-375
While research on children is supported by many professional guidelines, international declarations and domestic legislation, when it is undertaken on children with no possibility of direct benefit it rests on shaky moral foundations. A number of authors have suggested that research enrolment is in the child's best interests, or that they have a moral duty or societal obligation to participate. However, these arguments are unpersuasive. Rather, I will propose in this paper that research participation by children seems most reasonable when considered as an act of solidarity; a form of identification with, and provision of practical assistance to, those who are less well off. This is an articulation of the view that many children, and their parents, seem to take seriously the suffering of others, and wish to assist in advancing other children's wellbeing. Perhaps, by fostering an environment in which children are encouraged to take solidarity seriously, participation in research which holds out substantial hope of benefit to those less well off would come to be perceived as a behavioural norm rather than an exceptional practice.  相似文献   

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Edwards SJ 《Bioethics》2006,20(2):77-91
In this paper, I support the claim that placing certain restrictions on public access to possible new treatments is morally problematic under some exceptional circumstances. Very ill patients may find that all available standard treatments are unacceptable, either because they are ineffective or have serious adverse effects, and these patients may understandably be desperate to try something new even if this means stepping into the unknown. Faced with certain death, it is rational to want to try something new and to chance a dire outcome. Restricting possible new treatments to research trials may put these treatments scientifically, geographically or economically out of reach of these patients. For those who can get access, research restrictions could weaken, though not necessarily eliminate, the value of consent participants of such trials are able to give. Some participants may therefore be exploited for scientific purposes in the name of public interest. There are nonetheless compelling reasons for keeping some restrictive regulation in this area.  相似文献   

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While conceding that time has proven him wrong in doubting public acceptance of the idea of the "science shops," first sponsored by the Free University of Amsterdam to provide access to technical expertise for customers who could not afford more orthodox services, the author remains convinced that the somewhat analogous concept of "fee for service research," which offers experimental medical treatments for those who can afford to pay for them, is wrong. Such research has been justified as a private sector enterprise that provides patients who are unresponsive to standard forms of therapy with scientifically sound experimental options. However, the objections that such work might be kept secret and not contribute to medical knowledge, and that therapy would be available only to the rich, remain unanswered and pose an insurmountable obstacle to the support of this idea.  相似文献   

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The identification of plasma proteins that systematically change with age and, independent of chronological age, predict accelerated decline of health is an expanding area of research. Circulating proteins are ideal translational “omics” since they are final effectors of physiological pathways and because physicians are accustomed to use information of plasma proteins as biomarkers for diagnosis, prognosis, and tracking the effectiveness of treatments. Recent technological advancements, including mass spectrometry (MS)‐based proteomics, multiplexed proteomic assay using modified aptamers (SOMAscan), and Proximity Extension Assay (PEA, O‐Link), have allowed for the assessment of thousands of proteins in plasma or other biological matrices, which are potentially translatable into new clinical biomarkers and provide new clues about the mechanisms by which aging is associated with health deterioration and functional decline. We carried out a detailed literature search for proteomic studies performed in different matrices (plasma, serum, urine, saliva, tissues) and species using multiple platforms. Herein, we identified 232 proteins that were age‐associated across studies. Enrichment analysis of the 232 age‐associated proteins revealed metabolic pathways previously connected with biological aging both in animal models and in humans, most remarkably insulin‐like growth factor (IGF) signaling, mitogen‐activated protein kinases (MAPK), hypoxia‐inducible factor 1 (HIF1), cytokine signaling, Forkhead Box O (FOXO) metabolic pathways, folate metabolism, advance glycation end products (AGE), and receptor AGE (RAGE) metabolic pathway. Information on these age‐relevant proteins, likely expanded and validated in longitudinal studies and examined in mechanistic studies, will be essential for patient stratification and the development of new treatments aimed at improving health expectancy.  相似文献   

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Shaw DM 《Bioethics》2008,22(4):218-223
Many people have moral qualms about embryo research, feeling that embryos must deserve some kind of protection, if not so much as is afforded to persons. This paper will show that these qualms serve to camouflage motives that are really prudential, at the cost of also obscuring the real ethical issues at play in the debate concerning embryo research and therapeutic cloning. This in turn leads to fallacious use of the Actions/Omissions Distinction and ultimately neglects the duties that we have towards future persons.  相似文献   

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Background

The growth and acceptance of osteopathic physicians as conventional medical practitioners in the United States has also raised questions about the distinctive aspects of osteopathic medicine. Although the use of osteopathic manipulative treatment (OMT) and a focus on primary care are most often cited as rationales for the uniqueness of osteopathic medicine, an osteopathic professional identity remains enigmatic.

Discussion

The fledgling basic osteopathic research efforts of the early and mid-twentieth century have not been sustained and expanded over time. Thus, there is presently a scarcity of basic mechanistic and translational research that can be considered to be uniquely osteopathic. To be sure, there have been advances in osteopathic clinical trials, particularly those involving OMT for low back pain. Meta-analysis of these low back pain trials has provided evidence that: (1) OMT affords greater pain reduction than active or placebo control treatments; (2) the effects of OMT are comparable regardless of whether treatment is provided by fully-licensed osteopathic physicians in the United States or by osteopaths in the United Kingdom; and (3) the effects of OMT increase over time. However, much more clinical research remains to be done. The planning and implementation of a large longitudinal study of the natural history and epidemiology of somatic dysfunction, including an OMT component, represents a much-needed step forward. Osteopathic medicine's use of OMT and its focus on primary care are not mutually exclusive aspects of its uniqueness. The intersection of these fundamental aspects of osteopathic medicine suggests that the profession may successfully adopt a generic strategy of "focused differentiation" to attain a competitive advantage in the health care arena. While there are both requisite demands and risks for the osteopathic profession in adopting such a strategy, these are reasonable in relation to the potential rewards to be attained. To help promote an osteopathic identity, "omtology" and its derivative terms are recommended in referring to the study of OMT.

Conclusion

The osteopathic profession should adopt a coherent strategy for developing and promoting its identity. Failure to do so will likely ensure that osteopathic medicine remains "stuck in the middle."  相似文献   

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