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91.
We describe here the first case of neonatal death due to the hyperornithinaemia, hyperammonaemia, and homocitrullinuria (HHH) syndrome and the first prenatal diagnosis of this disorder in a subsequent pregnancy in this family.  相似文献   
92.
The association between gestational infection with human parvovirus (B19) and fetal loss has increased interest in this virus and demand for diagnostic testing. However, serological assays for B19 are not yet widely available. Maternal serum alpha-fetoprotein (MSAFP) testing is commonly used during the second trimester to screen for various fetal defects. We attempted to determine whether an elevated level of MSAFP would be an appropriate indication for B19-specific tests. Over a 26-month period, MSAFP tests were performed at Michigan State University for 21 392 women. Sera remaining after that testing were stored frozen. Of these, 22 case samples—from women with MSAFP levels greater than 3·0 multiples of the median (MOM) and pregnancies that ended in fetal loss—and 44 matched control samples—from women with MSAFP levels greater than 0·4 and less than 2·2 MOM and live births at term—were tested for B19 antibodies. None of the 66 samples was IgM positive, while 33 (50 per cent) were IgG positive. The presence of IgG was not significantly associated with case or control status (matched odds ratio=0·77, 95 per cent confidence interval 0·28–2·11). These findings are consistent with other studies indicating prior infection in approximately half of adults and suggest that elevated screening MSAFP levels, in the absence of other evidence of B19 infection, should not prompt B19-specific testing.  相似文献   
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Green E  Donnelly R 《Ambio》2003,32(2):140-144
There are more than 200 marine protected areas (MPAs) in the Caribbean and Central America that contain coral reefs and are therefore theoretically attractive to scuba divers. One fifth of dive operators in 30 countries were surveyed for their use of MPAs: the majority are located within 20 km of at least one MPA and 46% conduct at least 80% of their diving within a MPA. An estimated 15 million dives take place outside of Florida each year, half of these occurring inside MPAs. Only 25% of MPAs containing coral reefs charge divers an entry or user fee, which is most usually USD 2-3 levied per dive or per diver. The revenue generated by these fees is estimated at USD 1-2 million annually, but the potential for generating income has not been fully realized. A significant contribution to the cost of regional conservation could be achieved if higher fees were applied more widely than at present.  相似文献   
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Theory suggests that maternal effects are especially important in organisms with environmentally-sensitive sex-determining mechanisms. However, there is no substantive body of empirical evidence to confirm this conjecture. We integrated field and laboratory studies to jointly evaluate the significance of behavioral (nest-site choice) and physiological (yolk hormone allocation) maternal effects on offspring sex ratio in the common snapping turtle (Chelydra serpentina), a species with temperature-dependent sex determination (TSD). Of the 16 microhabitat variables measured, only three (south, east, and total overstory vegetation cover) were significantly correlated with nest temperature: cooler nests were located under more vegetation cover. In turn, these microhabitat predictors of nest temperature, and nest temperature itself, may influence nest sex ratio: shadier, cooler nests were more likely to produce a higher proportion of male offspring than less shady, warmer nests. Analysis of eggs from these same nests incubated in a common garden design in the laboratory revealed that clutch sex ratio was unaffected by levels of yolk estradiol, yolk testosterone, or their interaction. Examination of both behavioral and physiological maternal effects revealed no concordant impact on offspring sex ratio. However, eggs from nests that produced male-biased sex ratios in the field yielded higher proportions of males under constant-temperature conditions in the laboratory. Our study confirms the importance of behavioral maternal effects in nature on offspring sex ratios in species with TSD, while also revealing the potential presence of a predisposition for sex-ratio production underlying TSD in this system.Communicated by S. Krackow  相似文献   
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植物保护品在农作物上的使用会导致鸟类和哺乳动物接触有毒化学物质。在欧盟,关于此类暴露的风险评估均以当前(2009)欧洲食品安全局(EFSA)颁布的指导性文件为依据,与之前的版本相比,该文件在理论风险评估的可实现性方面有所提高(SANCO/4145/2000)。自从7年前实施2009 EFSA 指导性文件以来,基于此已经对众多植物保护品的毒性进行了成功地评估。然而,在今后的修订版本中仍然存在需要改进的重要方面。这篇焦点文章讨论了目前方案的风险评估经验,包括输入参数的保守水平和监管当局的解释以及如何在不远的将来对指导性文件进行修订提出建议。明确了推进指导文件的几方面建议,例如与生态相关的鸟类和哺乳动物生殖端点的推导和情境风险评估中建模方法的使用。在完善现有数据库方面,本文也有所强调,包括校对全欧洲相关焦点物种和扩大食物残留数据库。为了能够在将来形成一个真实可用的指导性文件,强烈建议在产业、监管和欧洲食品安全局等部门之间进行开放和建设性的沟通和交流。这样的合作也将鼓励会员国之间的融合,从而减轻产业和监管机构工作负荷。
精选自Amy C. Brooks, Mike Fryer, Alan Lawrence, Juan Pascual, Rachel Sharp. Reflections on bird and mammal risk assessment for plant protection products in the European Union: past, present and future. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 565–575, July 2017. DOI: 10.1002/etc.3719
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3719/full
  相似文献   
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Reliable prediction of the unsaturated zone transport and attenuation of dissolved-phase VOC (volatile organic compound) plumes leached from shallow source zones is a complex, multi-process, environmental problem. It is an important problem as sources, which include solid-waste landfills, aqueous-phase liquid discharge lagoons and NAPL releases partially penetrating the unsaturated zone, may persist for decades. Natural attenuation processes operating in the unsaturated zone that, uniquely for VOCs includes volatilisation, may, however, serve to protect underlying groundwater and potentially reduce the need for expensive remedial actions. Review of the literature indicates that only a few studies have focused upon the overall leached VOC source and plume scenario as a whole. These are mostly modelling studies that often involve high strength, non-aqueous phase liquid (NAPL) sources for which density-induced and diffusive vapour transport is significant. Occasional dissolved-phase aromatic hydrocarbon controlled infiltration field studies also exist. Despite this lack of focus on the overall problem, a wide range of process-based unsaturated zone - VOC research has been conducted that may be collated to build good conceptual model understanding of the scenario, particularly for the much studied aromatic hydrocarbons and chlorinated aliphatic hydrocarbons (CAHs). In general, the former group is likely to be attenuated in the unsaturated zone due to their ready aerobic biodegradation, albeit with rate variability across the literature, whereas the fate of the latter is far less likely to be dominated by a single mechanism and dependent upon the relative importance of the various attenuation processes within individual site - VOC scenarios. Analytical and numerical modelling tools permit effective process representation of the whole scenario, albeit with potential for inclusion of additional processes - e.g., multi-mechanistic sorption phase partitioning, and provide good opportunity for further sensitivity analysis and development to practitioner use. There remains a significant need to obtain intermediate laboratory-scale and particularly field-scale (actual site and controlled release) datasets that address the scenario as a whole and permit validation of the available models. Integrated assessment of the range of simultaneous processes that combine to influence leached plume generation, transport and attenuation in the unsaturated zone is required. Component process research needs are required across the problem scenario and include: the simultaneous volatilisation and dissolution of source zones; development of appropriate field-scale dispersion estimates for the unsaturated zone; assessment of transient VOC exchanges between aqueous, vapour and sorbed phases and their influence upon plume attenuation; development of improved field methods to recognise and quantify biodegradation of CAHs; establishment of the influence of co-contaminants; and, finally, translation of research findings into more robust practitioner practice.  相似文献   
100.
PROBLEM: This study aimed to provide an assessment of the contribution of design to the occurrence of fatal work-related injuries in Australia. METHODS: The Australian National Coroners' Information System was the data source for fatal injuries. Deaths resulting from workplace injuries on or between 1 July 2000 and 30 June 2002 were included. RESULTS: Seventy seven (37%) of the 210 identified workplace fatalities definitely or probably had design-related issues involved. In another 29 (14%), the circumstances were suggestive that design issues were involved. The most common scenarios involved problems with rollover protective structures and/or associated seat belts; inadequate guarding; lack of residual current devices; inadequate fall protection; failed hydraulic lifting systems in vehicles and mobile equipment; and inadequate protection mechanisms on mobile plant and vehicles. SUMMARY: Design is a significant contributor to work-related fatal injury in Australia. There is considerable scope for preventing serious work-related injury through improving design of plant, equipment, and vehicles used for work-related purposes.  相似文献   
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