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C Gray 《CMAJ》1997,156(6):891-892
The National Forum on Health''s final report appears to have said what Canadians--and the federal Liberal government wanted to hear about the health care system. It called for preservation of the single-payer model and the 5 principles of the Canada Health Act, and also recommended that medicare be expanded to embrace pharmaceuticals and home care. Edmonton internist Tom Noseworthy, chair of the forum''s steering committee, said public anxiety about medicare is caused by the rapid pace of change, not its direction. However, the CMA''s Dr. Judith Kazimirski was quick to challenge Noseworthy and his criticism of those who say a crisis exists.  相似文献   

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Is biogeography emerging from its identity crisis?   总被引:2,自引:1,他引:1  
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Have we overstated the tropical biodiversity crisis?   总被引:4,自引:0,他引:4  
Tropical forests are the most biologically diverse and ecologically complex of terrestrial ecosystems, and are disappearing at alarming rates. It has long been suggested that rapid forest loss and degradation in the tropics, if unabated, could ultimately precipitate a wave of species extinctions, perhaps comparable to mass extinction events in the geological history of the Earth. However, a vigorous debate has erupted following a study by Wright and Muller-Landau that challenges the notion of large-scale tropical extinctions, at least over the next century. Here, I summarize this controversy and describe how the debate is stimulating a serious examination of the causes and biological consequences of future tropical deforestation.  相似文献   

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Recent years have seen an explosion in the availability of protozoan pathogen genome sequences. Although data regarding the underlying genome sequence remain relatively stable after the initial draft, understanding of specific gene function is increasing rapidly. This dichotomy is reflected in the relative stability of systematic gene identifiers (SysIDs(*)) in genome sequence databases, as compared to evolving and/or conflicting gene and gene product names. GenBank/EMBL/DDBJ accession numbers are important, but most protozoan parasite researchers use organism-based databases such as EuPathDB or GeneDB as their immediate resource for gene-based information because they not only provide sequence information but also functional information and links to references. Reference to SysIDs therefore provides a valuable bridge to this repository of information.  相似文献   

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Concerns have been raised that invertebrate pollinators of crops and wild plants are in decline as a result of modern agricultural practices, habitat degradation, and introduced pests and diseases. This has led to demands for a response by land managers, conservationists and political decision makers to the impending 'global pollinator crisis'. In questioning this crisis, it becomes apparent that perceptions of a pollinator crisis are driven mainly by reported declines of crop-pollinating honeybees in North America, and bumblebees and butterflies in Europe, whereas native pollinator communities elsewhere show mixed responses to environmental change. Additionally, few staple food crops depend on pollinator services, and most crops that do are grown at small scales in diversified agro-ecosystems that are likely to support healthy pollinator communities, or in highly managed systems that are largely independent of wild pollinators. Consequently, justifying conservation action on the basis of deteriorating pollinator services might be misplaced. Nevertheless, existing initiatives to monitor pollinators are well founded, given the uncertainty about the dynamics of pollinator populations.  相似文献   

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Knowledge of pollination services provided by flower visitors is a prerequisite for understanding (co)evolutionary processes between plants and their pollinators, for evaluating the degree of specialization in the pollination system, and for assessing threats from a potential pollination crisis. This study examined pollination efficiency and visitation frequency of pollinators--key traits of pollinator-mediated fecundity--in a natural population of the wild carnation Dianthus carthusianorum. The five lepidopteran pollinator species observed differed in pollination efficiency and visitation frequency. Pollinator importance, the product of pollination efficiency and visitation frequency, was determined by the pollinator's visitation frequency. Pollination of D. carthusianorum depended essentially on only two of the five recorded pollinator species. Seed set was pollen-limited and followed a saturating dose-response function with a threshold of c. 50 deposited pollen grains for fruit development. Our results confirm that D. carthusianorum is specialized to lepidopteran pollinators, but is not particularly adapted to the two main pollinator species identified. The local persistence of D. carthusianorum is likely to be at risk as its reproduction depends essentially on only two of the locally abundant, but generally vulnerable, butterfly species.  相似文献   

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The aim of the study was to examine patients in adolescent crisis at the beginning of treatment and after a period of 12 months in order to evaluate the relative diagnostic and therapeutic validity. The study included 153 Split University students in adolescent crisis; 90 of them were treated by counseling and 63 served as controls. For diagnosis, Hampstead index and Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV) multiaxial evaluation were used, allowing a wider insight into personal functioning. The study sample was split in 7 significantly different diagnostic subgroups. The counseling-treated examinees had better personality functioning after 12 months, but did not differ significantly from the control group. Some of their single functions were more severely disturbed at the very beginning. Counseling is a valuable therapeutic and diagnostic tool for adolescent crisis. The assessment must evaluate the entire person, because looking at only one aspect, due to different development and its place, a wrong conclusion may be reached. The "adolescents crisis" entity is clinically relevant.  相似文献   

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There is an urgent need for cost-effective strategies for the sustainable control of Trypanosoma brucei rhodesiense (Rhodesian) sleeping sickness, which is a fatal zoonotic disease that has caused devastating epidemics during the past century. Sleeping sickness continues to be controlled by crisis management, using active case detection, treatment and vector control - activities that occur only during major epidemics; during the intervening periods, farmers and communities must fend for themselves. There are several methods for assessing the burden of this disease and there is a series of farmer-led methodologies that can be applied to reduce the burden of human and animal trypanosomiases.  相似文献   

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Incentives to care for nonhuman animals derive in part from the extent to which people depend on animals for food, for livelihood, and for cultural and psychological reasons as well as from the duty to protect animals in their care. When attention is turned to solving and preventing animal welfare problems at times of crisis, it becomes clear that those problems are also associated with problems for human welfare and environmental impact. The incidence and spread of animal diseases is affected by how animals are treated, and this can have very important effects. Similarly, during disasters caused by either natural or human-made events, outcomes for animals are important both in themselves and for their effects on humans and the environment. The need to plan and prepare to care for animals in advance of disease pandemics and disasters—and then to provide coordinated, measured management in response when such crises occur—requires collaboration between all agencies involved as well as increasing attention and resources.  相似文献   

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An ontological crisis? A review of large felid conservation in India   总被引:1,自引:0,他引:1  
The need for a solid knowledge base to inform conservation activity is now universally recognised. We critically scrutinised the scientific knowledge of large felids in India located in peer-reviewed research papers to assess the information available to make landscape-level management decisions that aid conservation, which is a stated goal of both the Indian government and the international community. We found two striking patterns: the biological sciences dominate in the published literature, and nearly all the research has been carried out in protected areas, though a substantial number of large felids also live outside protected areas. We argue that these patterns are not incidental, but the result of the dualistic ontology of science that uses processes of ‘purification’ and ‘translation’ to fit complex realities into disciplinary prerogatives organised around creating dichotomies (like nature–culture). In addition, since this body of scientific knowledge locates large felids in ‘pure’ biological landscapes, there is little or no insight from multi-use landscapes. These findings, we believe, highlight important knowledge gaps in our present research-based knowledge of large felids in India, which urgently need to be addressed if progress is to be made in conservation.  相似文献   

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Abstract

Two recent studies have independently recovered Pisanosaurus mertii – long thought to represent the oldest known member of Ornithischia – within Silesauridae. These finds are expanded upon here, as are the implications of this hypothesis. Based upon these finds, it now appears that Ornithischia was absent in the Triassic Period entirely, which constitutes a major incongruence between the fossil record and current phylogenetic hypotheses, particularly the traditional model of dinosaur interrelationships in which Ornithischia and Saurischia are sister-taxa. It has been suggested previously that Ornithischia was simply a rare component of Late Triassic faunas, or that perhaps the clade’s ecology or geographic distribution were not conducive to producing a fossil record. Here I propose that phylogeny could hold the solution to this problem. I examine how an alternative position for Ornithischia – nested either within Theropoda or Sauropodomorpha – could be the reason behind their later appearance and relative rarity in the Early Jurassic. An Early Jurassic origin of Ornithischia would force us to consider that the anatomical similarities between ornithischians and Early Jurassic taxa might not be convergences, and to broaden the current datasets of early dinosaurs to test these ideas.  相似文献   

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