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71.
72.
Mammalian embryonic stem cells have the potential to differentiate into all cell types of an adult individual. The culturing
of human embryonic stem cells renders possible studies that were previously only available in animal models. Embryonic stem
cells constitute a particularly attractive tool for studies of self-renewal, commitment, differentiation, maturation and cell-cell
interaction. There is currently considerable hope that studies of embryonic stem cells will lead to new therapies; either
by themselves, through cell replacement strategies, or by generating results assisting other fields of research to reach clinical
results. There are, however, considerable challenges to be met before embryonic stem cells can be used in large-scale clinical
trials.Stem cell research is an area that has given rise to much debate internationally, within science, law and politics
as well as within philosophy and ethics. The ethical attitudes expressed in the public debate over stem cell research notably
divide over three important distinctions: (1) Reproductive versus therapeutic cloning; (2) Using already existing embryos
versus producing new embryos for research purposes; (3) Production of embryos from eggs and sperm versus through somatic-cell
nuclear transfer. The potential medical benefits that may result from embryonic stem cell research arguably support a continued
development in this area. However, some opponents argue that this research offends the (relative or absolute) moral status
of an unborn human. Furthermore, the research would probably prove to be a both time-consuming and very expensive method for
treating disease. Thus, the questions arise whom the new technique wouldbenefit and at what cost, if ever developed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
73.
Effects of climate change on biodiversity: a review and identification of key research issues 总被引:7,自引:2,他引:7
Maarten Kappelle Margret M.I. Van Vuuren Pieter Baas 《Biodiversity and Conservation》1999,8(10):1383-1397
Current knowledge of effects of climate change on biodiversity is briefly reviewed, and results are presented of a survey of biological research groups in the Netherlands, aimed at identifying key research issues in this field. In many areas of the world, biodiversity is being reduced by humankind through changes in land cover and use, pollution, invasions of exotic species and possibly climate change. Assessing the impact of climate change on biodiversity is difficult, because changes occur slowly and effects of climate change interact with other stress factors already imposed on the environment. Research issues identified by Dutch scientists can be grouped into: (i) spatial and temporal distributions of taxa; (ii) migration and dispersal potentials of taxa; (iii) genetic diversity and viability of (meta) populations of species; (iv) physiological tolerance of species; (v) disturbance of functional interactions between species; and (vi) ecosystem processes. Additional research should be done on direct effects of greenhouse gases, and on interactions between effects of climate change and habitat fragmentation. There are still many gaps in our knowledge of effects of climate change on biodiversity. An interdisciplinary research programme could possibly focus only on one or few of the identified research issues, and should generate input data for predictive models based on climate change scenarios. 相似文献
74.
陈耀康 《上海生物医学工程》2012,(2):130-133
产学研创新战略联盟是提升产品市场竞争力的手段,它集合了产业链中各相关单位资源,提供了解决瓶颈技术的平台,利益分享。该文介绍了联盟创建、成员的选择、风险控制、日常管理、利益分享等方面的经验。 相似文献
75.
Factors Affecting Women's Autonomous Decision Making In Research Participation Amongst Yoruba Women Of Western Nigeria 下载免费PDF全文
Chitu Womehoma Princewill Ayodele S. Jegede Karin Nordström Bolatito Lanre‐Abass Bernice Simone Elger 《Developing world bioethics》2017,17(1):40-49
Research is a global enterprise requiring participation of both genders for generalizable knowledge; advancement of science and evidence based medical treatment. Participation of women in research is necessary to reduce the current bias that most empirical evidence is obtained from studies with men to inform health care and related policy interventions. Various factors are assumed to limit autonomy amongst the Yoruba women of western Nigeria. This paper seeks to explore the experience and understanding of autonomy by the Yoruba women in relation to research participation. Focus is on factors that affect women's autonomous decision making in research participation. An exploratory qualitative approach comprising four focus group discussions, 42 in‐depth interviews and 14 key informant interviews was used. The study permits a significant amount of triangulation, as opinions of husbands and religious leaders are also explored. Interviews and discussions were audiotaped and transcribed verbatim. Content analysis was employed for data analysis. Findings show that concepts of autonomy varied amongst the Yoruba women. Patriarchy, religion and culture are conceived to have negative impact on the autonomy of women in respect to research participation. Among the important findings are: 1) male dominance is strongly emphasized by religious leaders who should teach equality, 2) while men feel that by making decisions for women, they are protecting them, the women on the other hand see this protection as a way of limiting their autonomy. We recommend further studies to develop culturally appropriate and workable recruitment methods to increase women's participation in research. 相似文献
76.
Shane Stafslien Justin Daniels Bret Mayo David Christianson Bret Chisholm Abdullah Ekin 《Biofouling》2013,29(1):45-54
Abstract A high-throughput bacterial biofilm retention screening method has been augmented to facilitate the rapid analysis and down-selection of fouling-release coatings for identification of promising candidates. Coatings were cast in modified 24-well tissue culture plates and inoculated with the marine bacterium Cytophaga lytica for attachment and biofilm growth. Biofilms retained after rinsing with deionised water were dried at ambient laboratory conditions. During the drying process, retained biofilms retracted through a surface de-wetting phenomenon on the hydrophobic silicone surfaces. The retracted biofilms were stained with crystal violet, imaged, and analysed for percentage coverage. Two sets of experimental fouling-release coatings were analysed with the high-throughput biofilm retention and retraction assay (HTBRRA). The first set consisted of a series of model polysiloxane coatings that were systematically varied with respect to ratios of low and high MW silanol-terminated PDMS, level of cross-linker, and amount of silicone oil. The second set consisted of cross-linked PDMS-polyurethane coatings varied with respect to the MW of the PDMS and end group functionality. For the model polysiloxane coatings, HTBRRA results were compared to data obtained from field immersion testing at the Indian River Lagoon at the Florida Institute of Technology. The percentage coverage calculations of retracted biofilms correlated well to barnacle adhesion strength in the field (R2 = 0.82) and accurately identified the best and poorest performing coating compositions. For the cross-linked PDMS-polyurethane coatings, the HTBRRA results were compared to combinatorial pseudobarnacle pull-off adhesion data and good agreement in performance was observed. Details of the developed assay and its implications in the rapid discovery of new fouling-release coatings are discussed. 相似文献
77.
We successfully integrated science and language arts in a third-grade classroom. The students used “scientist's eyes” and “poet's eyes” to write original poetry. In addition, they created habitat posters about a swamp organism. Scoring guides for the habitat poems and posters are also included. 相似文献
78.
Katharina Bork Johannes Karstensen Martin Visbeck Andreas Zimmermann 《Ocean Development & International Law》2013,44(3):298-328
This article analyzes the legal status of unmanned instruments (particularly, floats and gliders) for observation purposes in the ocean environment. These new kinds of instruments are being deployed by the thousands into the oceans, not the least as part of the Argo Project of the International Oceanographic Commission. Their uncontrolled drifting has raised legal questions, especially when such instruments enter waters subject to the jurisdiction of foreign states. The authors argue that the current international legal framework is insufficient to address the pertinent issues, and that a new legal regime is needed. 相似文献
79.
The ethical standards that regulate clinical research have multiple rationales. Among them is the need to protect potential subjects from making imprudent decisions, which extends beyond the soft paternalistic concern to protect people from making uninformed decisions to participate in trials. This article argues that a plausible risk/benefit restriction on clinical trials is presumptively justified by hard paternalism, which in turn is supported by a deeper fairness‐based rationale. This presumptive case for hard paternalism in research is not defeated by the alleged right to participate in clinical trials, by concerns about insult or status, by the need to conduct early phase trials that promise little to no benefit to participants, or by the recognition that some potential subjects are altruistically motivated. 相似文献
80.
This article considers the process of ethical review of research on human subjects at a very large multinational consumer products company. The commercial context of this research throws up unique challenges and opportunities that make the ethics of the process of oversight distinct from mainstream medical research. Reflection on the justification of governance processes sheds important, contrasting light on the ethics of governance of other forms and context of research. 相似文献