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41.
The use of thimerosal preservative in childhood vaccines has been largely eliminated over the past decade in the United States because vaccines have been reformulated in single‐dose vials that do not require preservative. An exception is the inactivated influenza vaccines, which are formulated in both multidose vials requiring preservative and preservative‐free single‐dose vials. As part of an ongoing evaluation by USFDA of the safety of biologics throughout their lifecycle, the infant body burden of mercury following scheduled exposures to thimerosal preservative in inactivated influenza vaccines in the United States was estimated and compared to the infant body burden of mercury following daily exposures to dietary methylmercury at the reference dose established by the USEPA. Body burdens were estimated using kinetic parameters derived from experiments conducted in infant monkeys that were exposed episodically to thimerosal or MeHg at identical doses. We found that the body burden of mercury (AUC) in infants (including low birth weight) over the first 4.5 years of life following yearly exposures to thimerosal was two orders of magnitude lower than that estimated for exposures to the lowest regulatory threshold for MeHg over the same time period. In addition, peak body burdens of mercury following episodic exposures to thimerosal in this worst‐case analysis did not exceed the corresponding safe body burden of mercury from methylmercury at any time, even for low‐birth‐weight infants. Our pharmacokinetic analysis supports the acknowledged safety of thimerosal when used as a preservative at current levels in certain multidose infant vaccines in the United States.  相似文献   
42.
ABSTRACT

Recently, the FDA announced that it would soon lift the long-standing lifetime ban on blood donation by men who have sex with men (MSM). Reexamining blood donation by MSM, it is clear that there are several ethical goods that must be balanced. Through balancing the primary duty to safety with the imperatives to craft a policy that is formally equal, upholds the public's trust, and is nondiscriminatory, an ethical blood donation deferral guideline may be advanced, both for MSM and the population at large.  相似文献   
43.
44.
《Risk analysis》2018,38(3):562-584
Currently, published risk analyses for drones refer mainly to commercial systems, use data from civil aviation, and are based on probabilistic approaches without suggesting an inclusive list of hazards and respective requirements. Within this context, this article presents: (1) a set of safety requirements generated from the application of the systems theoretic process analysis (STPA) technique on a generic small drone system; (2) a gap analysis between the set of safety requirements and the ones met by 19 popular drone models; (3) the extent of the differences between those models, their manufacturers, and the countries of origin; and (4) the association of drone prices with the extent they meet the requirements derived by STPA. The application of STPA resulted in 70 safety requirements distributed across the authority, manufacturer, end user, or drone automation levels. A gap analysis showed high dissimilarities regarding the extent to which the 19 drones meet the same safety requirements. Statistical results suggested a positive correlation between drone prices and the extent that the 19 drones studied herein met the safety requirements generated by STPA, and significant differences were identified among the manufacturers. This work complements the existing risk assessment frameworks for small drones, and contributes to the establishment of a commonly endorsed international risk analysis framework. Such a framework will support the development of a holistic and methodologically justified standardization scheme for small drone flights.  相似文献   
45.
Peers and friends are perceived as important role models for the formation of children's attitudes and behaviours. A wealth of research has aimed to establish the contribution of peers and friends to children's developing eating behaviours, and their attitudes towards eating. This review describes and evaluates such research. Experimental research examining peer modelling of food consumption and liking is reviewed, and several individual child factors that are suggested to make children more or less receptive to peer and friend influences are discussed. The influence of children's perceptions of their peers’ and friends’ eating behaviours upon their own eating practices is also explored. The benefits of future longitudinal research to improve understanding of peer and friend influences on children's eating are emphasized.  相似文献   
46.
Semisoft cheese made from raw sheep's milk is traditionally and economically important in southern Europe. However, raw milk cheese is also a known vehicle of human listeriosis and contamination of sheep cheese with Listeria monocytogenes has been reported. In the present study, we have developed and applied a quantitative risk assessment model, based on available evidence and challenge testing, to estimate risk of invasive listeriosis due to consumption of an artisanal sheep cheese made with raw milk collected from a single flock in central Italy. In the model, contamination of milk may originate from the farm environment or from mastitic animals, with potential growth of the pathogen in bulk milk and during cheese ripening. Based on the 48‐day challenge test of a local semisoft raw sheep's milk cheese we found limited growth only during the initial phase of ripening (24 hours) and no growth or limited decline during the following ripening period. In our simulation, in the baseline scenario, 2.2% of cheese servings are estimated to have at least 1 colony forming unit (CFU) per gram. Of these, 15.1% would be above the current E.U. limit of 100 CFU/g (5.2% would exceed 1,000 CFU/g). Risk of invasive listeriosis per random serving is estimated in the 10?12 range (mean) for healthy adults, and in the 10?10 range (mean) for vulnerable populations. When small flocks (10–36 animals) are combined with the presence of a sheep with undetected subclinical mastitis, risk of listeriosis increases and such flocks may represent a public health risk.  相似文献   
47.
The Mexican legend of ‘La Llorona’ (‘The Weeping Woman’), who drowned her children out of revenge for being abandoned by her lover, and the Aztec creation myth of ‘The Hungry Woman’ — crying constantly for food, with mouths all around her body — have inspired Chicana writers in the symbolic representation of their own yearning, be it sexual, identity-building, or anti-patriarchal. This essay seeks to lay the mythical groundwork within this topic, as well as to illustrate with some particular examples the different reappropriations of these myths in Cherríe L. Moraga, mainly in her play The Hungry Woman: A Mexican Medea (2001). With a view to opening up a past ‘that can provide a kind of road map to our future’ (: ix), these examples of transgressive women will be deprived of the feminine colonial passivity imbued by the dominant male discourse, and analysed as a complex, active, polyvalent mythological female corpus that integrates both life and death, womb and grave. This hybrid approach is inherent to the Aztec mythology on which Moraga relies in order to transcend Manichaeistic resolutions and probe the social, political, and gender reasons leading a hungry mother to commit infanticide.  相似文献   
48.
国外立法例对侵权法中作为义务的规制模式不尽相同,中国台湾地区和大陆地区理论界对作为义务的研究在结合中国司法实践方面略显不足。对于侵权法中作为义务的探究,应当将国外立法例、中国理论界的研究成果与司法实践情况结合起来。中国侵权法中作为义务的设计应当遵循如下思路:无须在一般条款中明确作为义务;合同约定不应成为侵权法中作为义务的来源;不应当规定一般救助义务;作为义务来源应当具有层级性,且该层级性应当以重塑安全保障义务为中心。  相似文献   
49.
伴随着经济的飞速发展,社会管理体制绝不能产生任何滞后。随着经济社会各领域发生深刻地变化,由政府高度主导的社会管理模式亦需要与时俱进地创新。作为国家特别行政区之一的澳门,近年来在经济上取得长足发展、政府公共财政收入颇为理想的情况下,不断探索"以民为本"的社会管理模式,努力辅助弱势社群,解决社会问题,持续营造良好的社会环境,促进社会和谐。澳门特区近年来推出的"社会企业"和"食物银行",是澳门政府现阶段社会管理的着力举措,体现出澳门特区的社会管理体制创新的特点。  相似文献   
50.
侗族先民以生产糯稻为主,并利用稻田养鱼鸭,创造了侗族地区“稻鱼鸭共生”的原始有机农业文化经典形式。侗族特有的生存环境和农耕方式,形成了侗族人民食不离酸、喜糯食、喜酒、好鱼、茶饮独特等饮食特点及文化。侗族的原生食品加工方法独特,选料考究,营养价值高,富含各种人体所必需的营养物质,特别是以鱼类为加工原料的侗族酸食富含人体所需的可溶性钙是新鲜鱼食品的16倍以上,“稻鱼鸭共生”系统成为侗族食材的一个重要来源。稻鱼鸭复合系统保证了侗族传统食品的特殊性及无公害性,只有优质的传统原生态食材才能保证传统民族食品的传统性,保护“稻鱼鸭共生”系统不仅为民族食品的传承和发展提供了原料的保障,也为侗族传统食品产业化打下了坚实的原料供给基础。  相似文献   
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