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J Bennett 《CMAJ》1997,157(7):938-939
The handful of "medical men" who founded the CMA 130 years ago this month could not have predicted the changes their association would witness. In this article Dr. John Bennett discusses some of these changes and considers some of the issues that may lie ahead.  相似文献   

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Cancer still represents a “nightmare” worldwide, causing annually millions of victims. Several antiproliferative molecules are currently used as drugs market and offer a pharmaceutical opportunity for attenuating and treating tumor manifestations. In this context, natural sources have a relevant role, since they provide the 60% of currently-used anticancer agents. Among the numerous natural products, acting via different mechanisms of action, microtubule-targeting agents (MTAs) have a high therapeutic potential, since they disrupt the abnormal cancer cell growth, interfering with the continuous mitotic division. Vinca alkaloids (VAs) are the earliest developed MTAs and approved for clinical use (Vincristine, Vinblastine, Vinorelbine, Vindesine, and Vinflunine) as agents in the treatment of hematological and lymphatic neoplasms. Here, we review the state-of-art of VAs, discussing their mechanism of action and pharmacokinetic properties and highlighting their therapeutic relevance and toxicological profile. Additionally, we briefly disclosed the technological approaches faced so far to ameliorate the pharmacological properties, as well as to avoid the drug resistance. Lastly, we introduced the recent advances in the discovery of new derivatives.  相似文献   

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Abstract

This paper seeks to compare the two major law of the sea conferences of the post‐World War II period in terms of imperatives for moving toward a more equitable international system. Transitions in the international system which have taken place in the years between the conferences are analyzed, as well as differences in conference participation and procedures. The paper then focuses upon the necessity for policy to be formulated in such a way that imbalances in opportunities for utilization of the seas are redressed. Special attention is given the status of the landlocked and geographically disadvantaged states. The 1977 Negotiating Text is commented on from this perspective. Proposals for development of ocean law/policy in UNCLOS III more congruent with achievement of global equity are then set forth.  相似文献   

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Ecologists, economists and other social scientists have much incentive for interaction. First of all, ecological systems and socioeconomic systems are linked in their dynamics, and these linkages are key to coupling environmental protection and economic growth. Beyond this, however, are the obvious similarities in how ecological systems and socioeconomic systems function, and the common theoretical challenges in understanding their dynamics. This should not be surprising. Socioeconomic systems are in fact ecological systems, in which the familiar ecological phenomena of exploitation, cooperation and parasitism all can be identified as key features. Or, viewed from the opposite perspective, ecological systems are economic systems, in which competition for resources is key, and in which an evolutionary process shapes the individual agents to a distribution of specialization of function that leads to the emergence of flows and functionalities at higher levels of organization. Most fundamentally, ecological and socioeconomic systems alike are complex adaptive systems, in which patterns at the macroscopic level emerge from interactions and selection mechanisms mediated at many levels of organization, from individual agents to collectives to whole systems and even above. In such complex adaptive systems, robustness must be understood as emergent from selection processes operating at these many different levels, and the inherent nonlinearities can trigger sudden shifts in regimes that, in the case of the biosphere, can have major consequences for humanity. This lecture will explore the complex adaptive nature of ecosystems, and the implications for the robustness of ecosystem services on which we depend, and in particular examine the conditions under which cooperative behavior emerges. It will then turn attention to the socioeconomic systems in which environmental management is based, and ask what lessons can be learned from our examination of natural systems, and how we can modify social norms to achieve global cooperation in managing our common future. Of special interest will be issues of intragenerational and intergenerational equity, and the importance of various forms of discounting.  相似文献   

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Biologists have recently devoted increasing attention to the role of rapid evolution in species' responses to environmental change. However, it is still unclear what evolutionary responses should be expected, at what rates, and whether evolution will save populations at risk of extinction. The potential of biological invasions to provide useful insights has barely been realised, despite the close analogies to species responding to global change, particularly climate change; in both cases, populations encounter novel climatic and biotic selection pressures, with expected evolutionary responses occurring over similar timescales. However, the analogy is not perfect, and invasive species are perhaps best used as an upper bound on expected change. In this article, we review what invasive species can and cannot teach us about likely evolutionary responses to global change and the constraints on those responses. We also discuss the limitations of invasive species as a model and outline directions for future research.  相似文献   

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The year 2020 provided a wake-up call about the role systemic racism plays in shaping our nation and shaping science. While hard work and great mentors helped bring me a long way from a farm in Minnesota, it’s become much clearer that the privilege of being white and male and the accumulated advantages that began there played powerful roles. It’s time for white scientists like me to listen, think, and take action.

We all have personal stories that we use to describe our trajectory in life and science. For the past five decades the narrative I told myself was a simple one of good luck, hard work, support from my community, and mentors at pivotal times. However, in many important ways, this was just a small part of the truth, ignoring the role unperceived privilege played. The many underlying injustices that were laid bare in our nation this past year began to open my eyes, prompting me to look back at the roles hidden privilege played in my career and the power that these have given me. This challenged me to use the power of that privilege to speak and act to try to change the system in which engrained advantages benefit some but not all. I am telling my story in hopes it will encourage my white colleagues to examine their own.  相似文献   

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Environmental DNA (eDNA) analysis is increasingly used for biomonitoring and research of fish populations and communities by environmental resource managers and academic researchers. Although managers are much interested in expanding the use of eDNA as a survey technique, they are sceptical about both its utility (given that information is often limited to presence/absence of a species) and feasibility (given the need for proper laboratory facilities for sample processing). Nonetheless, under the right circumstances, eDNA analysis is cost-effective compared to many traditional aquatic survey methods and does not disturb habitat or harm the animals being surveyed. This article presents a case study in which eDNA analysis was successfully used to document the presence of a rare fish species in a waterway earmarked for restoration. The authors discuss the conditions that allowed this study to occur quickly and smoothly and speculate on how the goals of researchers and managers can be integrated for efficient and informative use of this tool.  相似文献   

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In searching for a next generation molecule to the novel wake promoting agent modafinil (compound 1), a series of fluorene-derived wakefulness enhancing agents were developed and evaluated in rat. Extensive pharmacokinetic studies of a potent member of the series (compound 15) revealed that the wake promotion activity of the analog was likely due to an active metabolite (compound 3).  相似文献   

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