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排序方式: 共有2635条查询结果,搜索用时 15 毫秒
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Anika M. Helferich Sarah J. Brockmann Jörg Reinders Dhruva Deshpande Karlheinz Holzmann David Brenner Peter M. Andersen Susanne Petri Dietmar R. Thal Jens Michaelis Markus Otto Steffen Just Albert C. Ludolph Karin M. Danzer Axel Freischmidt Jochen H. Weishaupt 《Cellular and molecular life sciences : CMLS》2018,75(23):4301-4319
934.
Environmental health research produces scientific knowledge about environmental hazards crucial for public health and environmental justice movements that seek to prevent or reduce exposure to these hazards. The environment in environmental health research is conceptualized as the range of possible social, biological, chemical, and/or physical hazards or risks to human health, some of which merit study due to factors such as their probability and severity, the feasibility of their remediation, and injustice in their distribution. This paper explores the ethics of identifying the relevant environment for environmental health research, as judgments involved in defining an environmental hazard or risk, judgments of that hazard or risk's probability, severity, and/or injustice, as well as the feasibility of its remediation, all ought to appeal to non-epistemic as well as epistemic values. I illustrate by discussing the case of environmental lead, a housing-related hazard that remains unjustly distributed by race and class and is particularly dangerous to children. Examining a controversy in environmental health research ethics where researchers tested multiple levels of lead abatement in lead-contaminated households, I argue that the broader perspective on the ethics of environmental health research provided in the first part of this paper may have helped prevent this controversy. 相似文献
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Parkhill J Sebaihia M Preston A Murphy LD Thomson N Harris DE Holden MT Churcher CM Bentley SD Mungall KL Cerdeño-Tárraga AM Temple L James K Harris B Quail MA Achtman M Atkin R Baker S Basham D Bason N Cherevach I Chillingworth T Collins M Cronin A Davis P Doggett J Feltwell T Goble A Hamlin N Hauser H Holroyd S Jagels K Leather S Moule S Norberczak H O'Neil S Ormond D Price C Rabbinowitsch E Rutter S Sanders M Saunders D Seeger K Sharp S Simmonds M Skelton J Squares R Squares S Stevens K 《Nature genetics》2003,35(1):32-40
Bordetella pertussis, Bordetella parapertussis and Bordetella bronchiseptica are closely related Gram-negative beta-proteobacteria that colonize the respiratory tracts of mammals. B. pertussis is a strict human pathogen of recent evolutionary origin and is the primary etiologic agent of whooping cough. B. parapertussis can also cause whooping cough, and B. bronchiseptica causes chronic respiratory infections in a wide range of animals. We sequenced the genomes of B. bronchiseptica RB50 (5,338,400 bp; 5,007 predicted genes), B. parapertussis 12822 (4,773,551 bp; 4,404 genes) and B. pertussis Tohama I (4,086,186 bp; 3,816 genes). Our analysis indicates that B. parapertussis and B. pertussis are independent derivatives of B. bronchiseptica-like ancestors. During the evolution of these two host-restricted species there was large-scale gene loss and inactivation; host adaptation seems to be a consequence of loss, not gain, of function, and differences in virulence may be related to loss of regulatory or control functions. 相似文献
939.
The stomach contents were examined from 324 western Washington bobcats ( Felis rufus ) and 123 from eastern Washington taken by hunters from 1976 through 1980, for major prey items as well as sex- and age-related differences in diet. Western Washington bobcats ate primarily mountain beavers ( Aplodontia rufa ) (42% occurrence) and snowshoe hares ( Lepus americanus ) (26%). Within that population females ate larger quantities of smaller prey such as douglas squirrels ( Tamiasciurus douglasi ) and lesser amounts of deer ( Odocoileus sp.) than males. Bobcat diets in eastern Washington were more diverse; main foods consisted of lagomorphs ( Sylvilagus nuttallii, Lepus sp.) (20%), red squirrels ( Tamiasciurus hudsonicus ) (15%), deer (11%), and voles ( Microtus sp.) (11%). Age-related differences were most prevalent in this population, with adults consuming larger quantities of deer and larger prey than did kittens. 相似文献
940.
David M. Stoms Frank W. Davis Kenneth L. Driese Kelly M. Cassidy Michael P. Murray 《西北部美国博物学家》2011,58(3)
A conservation gap analysis was conducted for the Intermountain Semi-Desert ecoregion to assess the representation of land-cover types within areas managed primarily for biodiversity objectives. Mapped distributions of plant communities were summarized by land-management status categories. The total amount of land permanently protected in the ecoregion is < 4%, and most types that are characteristic of the region have < 10%. Of 48 land-cover types, 20 were found to be particularly vulnerable to potential loss or degradation because of low level of representation in biodiversity management areas and the impact of expected land-use activities. Gap analysis data and findings will be useful in providing a regional perspective in project impact assessment and future conservation planning within this ecoregion. 相似文献