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91.
Meta-analysis of randomized studies on the use of low-dose aspirin in women at high risk of preeclampsia (PE) has demonstrated that if treatment is initiated at ≤16 weeks' gestation, there is significant reduction in the risk of PE [relative risk (RR) 0.47, 95% confidence interval (CI) 0.36–0.62], fetal growth restriction (RR 0.46, 95% CI 0.33–0.64), preterm birth (RR 0.35, 95% CI 0.22–0.57) and perinatal death (RR 0.41, 95% CI 0.19–0.92), whereas the effect of treatment after 16 weeks is substantially less (RR 0.78, 95% CI 0.61–0.99; RR 0.98, 95% CI 0.88–1.08; RR 0.90, 95% CI 0.83–0.97; and RR 0.93, 95% CI 0.73–1.19, respectively). Moreover, the decrease in the risk of PE from early onset treatment seems to be related to the dose of aspirin, and a dose of >80 mg daily should be considered for optimal benefits. © 2014 John Wiley & Sons, Ltd.  相似文献   
92.
93.
Environmental lead (Pb) exposure and toxicity have been recognised as public health problems of global importance, affecting both the developed and developing nations. In this work, blood Pb of pregnant women that were not exposed to lead by their occupation (n?=?349), with mean ± SD age of 27.0?±?4.8 years and gestational age of 21.8?±?3.1 weeks at recruitment were determined using atomic absorption spectrophotometer. The results showed that 309 (88.5 %) of the women had a mean?±?SD blood Pb of 40.0?±?16.5 μg/dl, which is higher than the current US Centre for Disease Prevention and Control action limit (>10 μg/dl). The observed high prevalence of elevated blood Pb levels may be related to maternal low socioeconomic status. Health education is, therefore, urgently needed to sensitise the general public and the policy makers of the level of Pb exposure in Abakaliki environment and the inherent health implications. In addition to mandatory environmental lead monitoring, blood Pb screening for would-be mother is recommended, and those whose blood Pb are found elevated should be appropriately treated.  相似文献   
94.
The purpose of this paper is to reflect on accident causation models and accident investigation methods. Theories on accident causation and the modelling of accident mechanisms, as well as a number of methods for accident investigation have been developed and described in the literature. The evolution of accident causation models over time shows a shift from the sequence of events to the representation of the whole system. Respectively, the evolution of accident investigation methods over time reveals a gradual shift from searching for a single immediate cause, to the recognition of multiple causes. In order to evaluate the accident investigation methods, specific plausible requirements were established in order to verify that a specific accident investigation method fulfils the principles of a specific accident causation model or give evidence to the degree of alignment between them. Since different models approach accident causation in different ways, methods linked to these models provide fragmentary information regarding the accident. It is therefore expected that using a combination of model-method pairs could provide a more reliable platform for accident analysis.  相似文献   
95.
This paper proposes a new systemic modeling approach using the unified modeling language (UML) as an operational tool to model a complex industrial system and analyzes its risks. This approach is presented as a modeling process divided into three phases corresponding to functional analysis, structural analysis and risk analysis. This study aims to formalize the interactions within an industrial system and to identify the abnormal situations which could generate risks. The application of this approach is demonstrated with an example of a storage unit of chemical products located in Morocco. This approach provides a comprehensive view that facilitates the understanding of the organization of an industrial system and leads to more effective analysis of its safety.  相似文献   
96.
This paper makes a proposition that Epworth's current housing management policies, regulations and practices do not promote easy access to formal standard housing and secure tenure in peri-urban and urban areas for low-income groups. In constructing this paper, both qualitative and quantitative methodologies were used. The qualitative methods adopted include key informant interviews, observations of the environmental aspects of the study area and documentary analysis of secondary data housed in the local board (Epworth Local Board) offices. The major findings demonstrate the reasons for high levels of squatting in Epworth, the local board's housing and development control policy, the relationship between poverty and informal settlements, the informal settlers' capacity to meet the costs of planned and serviced stands and policy options for both the central government and the local board which can be adopted to alleviate poverty in informal settlements. Evidence on the ground points to the fact that perpetuated animosity among groups in a settlement hinders the growth and development of that place. Epworth is a victim of disharmony of the groups residing there. It is the group dynamics that are very influential in making or breaking development in a place. The government official position on Epworth in this study stands unconvincing regarding the jeopardy of bad stewardship by the so-called responsible authority.  相似文献   
97.
Journal of Material Cycles and Waste Management - The generation of biomass wastes is a huge concern as they have to be properly managed to ensure environmental wellbeing. This article examined...  相似文献   
98.
Environmental Science and Pollution Research - Land use changes have led to the degradation of multiple ecosystem services and affected the quality of aquatic ecosystems. The aims of this study...  相似文献   
99.
Environmental Science and Pollution Research - The present study, conducted in the Galion Bay in Martinique, aims to highlight the temporal and seasonal variations of chlordecone contamination (an...  相似文献   
100.
Synodontis (Mochokidae, Siluriformes) is a freshwater catfish endemic to Africa. The 118 extant species are present in almost all hydrographic basins. Some species are restricted to a single stream, whereas others have a vast distribution. Synodontis is known in the fossil record since the Miocene, and its history depends on the connections among African basins through time. The identification of species in the fossil record is essential to reconstruct this historical pattern. Catfish pectoral and dorsal spines are robust, they preserve well and they form most of the fossil remains for the genus Synodontis. Unfortunately, the criteria for the identification of extant Synodontis species are not applicable to fossil specimens. Here, we define 11 original morphological characters that permit to discriminate four extant species from the Chad-Chari hydrographic system. Six of these characters are defined on pectoral spines and five on dorsal spines. We then show that these characters can be used successfully for identifying fossil specimens. In particular, we present a case study in which we identify Synodontis cf. schall and Brachysynodontis cf. batensoda in the hominid-bearing sector Toros-Menalla (Late Miocene, northern Chad). We show that spine anatomy can be a powerful tool to recognise catfish species through time and thus to identify historical diversity pattern.  相似文献   
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