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151.
An amniocentesis was performed on a 22-week pregnancy following the detection of foetal abnormalities on ultrasound. A rapid aneuploid screen using fluorescence in situ hybridisation on uncultured amniotic fluid cells revealed 3 signals for chromosome 21, consistent with trisomy 21. In situ metaphase cultures revealed a 46,XY normal male karyotype. These discordant results may be explained by a sub-standard batch of the commercially available probe or alternatively, a very specific variation within the sample interacting with the probe. Alternative strategies are proposed in order to safeguard against inappropriate clinical action as a consequence of discordant results. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
152.
The October 2005 earthquake in northern Pakistan severely affected the livelihoods of 1.5 million people. With the destruction of material assets and communications infrastructure, the quake had a devastating impact on people's way of life in this remote mountainous region. This paper explores livelihood revival interventions undertaken during the earthquake response, and considers how differentiated livelihood outcomes were achieved. In addressing this objective the paper examines livelihood rehabilitation schemes in terms of structural aspects, working strategies, key factors, strengths of interventions and the role of human agency in influencing livelihood trajectories of quake‐affected communities. Primary data for this study was gathered in northern Pakistan between October 2008 and January 2009. The study identifies structural shortcomings and strengths of the programmes attempting to revive the livelihoods of poor and vulnerable households. It identifies how households in two villages made the most of opportunities to improve their lives and move towards favourable outcomes.  相似文献   
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155.
Concentrations of Zn and Cd were measured in fruitbodies of ectomycorrhizal (ECM) fungi and leaves of co-occurring accumulator aspen. Samples were taken on three metal-polluted sites and one control site. Fungal bioconcentration factors (BCF = fruitbody concentration: soil concentration) were calculated on the basis of total metal concentrations in surface soil horizons (BCFtot) and NH4NO3-extractable metal concentrations in mineral soil (BCFlab). When plotted on log-log scale, values of BCF decreased linearly with increasing soil metal concentrations. BCFlab for both Zn and Cd described the data more closely than BCFtot. Fungal genera differed in ZnBCF but not in CdBCF. The information on differences between fungi with respect to their predominant occurrence in different soil horizons did not improve relations of BCF with soil metal concentrations. Aspen trees accumulated Zn and Cd to similar concentrations as the ECM fungi. Apparently, the fungi did not act as an effective barrier against aspen metal uptake by retaining the metals.  相似文献   
156.
Phosphogypsum (PG), a byproduct of the phosphate fertilizer industry, was produced and stockpiled at the Agrium Fort Saskatchewan facility from 1965 to 1991. Upon decommissioning, the outer slopes of the PG stacks were reclaimed by applying 15 cm of topsoil and planting a non-native seed mix. Physical, chemical, and hydrologic evaluations of the cover system confirmed that plants were successfully growing in various soil capping depths and were often rooting more than 200 mm into the PG. Percolation past the substrate into PG during a typical storm event was low (< 10 mm), and runoff from the stacks was negligible. Runoff quality met most guidelines, but some parameters, including fluoride, were up to 18 times higher than provincial or federal guidelines for soil and water quality. However, the cover system, when applied appropriately, does meet basic reclamation objectives. The exceedances are found in areas where the cover system has been compromised by erosion or mixing or in areas where the cover system has not been fully applied, such as roads or the inner basin. In areas where the cover system has been applied successfully, basic reclamation requirements are met.  相似文献   
157.

Background, aim, and scope  

In this study, a suite of sublethal stress biomarkers were analyzed in juveniles of the sentinel species, the Pacific oyster Crassostrea gigas, with a view to using them as pollution monitoring tools. The aim of this work was (1) to study baseline seasonal variations of biomarkers in different body compartments of C. gigas in the reference site and, after selecting biomarkers presenting no seasonal variations, (2) to compare responses of these biomarkers between contaminated and reference sites.  相似文献   
158.
In this study a combined approach of bioindication results correlated with an extensive set of data on air pollution and climate was used to assess the pollution status of the Man and Biosphere Reserve Wienerwald (Austria). Bryophytes served as impact indicators (via the Index of Atmospheric Purity-method IAP) at 30 sites as well as accumulation monitors for airborne trace elements (Al, Pb, V, S, Zn, Fe, Cu, Cr, Ni, Co, Mo, Cd, As, Sb and 16 EPA-PAHs) at 10 sites within the reserve. The results of these bioindication methods were subsequently correlated with further pollution (NO(2), SO(2) and dust) and climate data (precipitation, temperature and humidity). The findings obtained clearly indicate the following: Bryophyte distribution is solely influenced by the status of air quality, without interference by climatic or site-related factors, which is in contrast to several previous investigations. IAP-values correlated significantly with NO(2) (0.553; P=0.004), SO(2) winter values (0.511; P=0.013) and PM10 (dust) (0.561; P=0.013). The results obtained via chemical analyses revealed a strong correlation with data derived from the IAP methodology. In terms of the overall air quality within the biosphere reserve Wienerwald, the north-eastern part appears to be the most affected one with a most likely pollution contribution emitted by the capital city Vienna, agriculture and neighbouring countries.  相似文献   
159.
In low-income countries, the use of some organochlorine pesticides is still common in order to increase food production. Monitoring the chemical exposure is an important step in risk-reducing strategies. This is the first study to report concentrations of organochlorines in breast milk of women from Bangladesh where farming is the main income source.Organochlorines such as p,p′-DDT, o,p′-DDT, p,p-DDE, p,p-DDD (i.e., ∑DDT), HCB, α-, β- and γ-HCH, trans-chlordane, cis-chlordane, oxy-chlordane, trans-nonachlor, cis-nonachlor, mirex and polychlorinated biphenyls (CB 28, 52, 99, 101, 105, 114, 118, 123, 128, 138, 141, 149, 153, 156, 157, 163, 167, 170, 180, 183, 187, 189, 194) were analyzed in breast milk collected in 2002 from 72 first-time mothers (median age 20 years) living in the rural area Matlab, Bangladesh.While the concentrations of PCBs and many of the pesticides were low, the concentrations of p,p′-DDT and its metabolite p,p′-DDE were high (median 349 and 1645 ng g−1 lipid, respectively) in comparison to other countries. The median value of ∑DDT was 2123 ng g−1 lipid. The estimated daily exposure to p,p′-DDT, p,p′-DDE and ∑DDTs was 10, 30 and 42 μg kg−1 body weight, respectively, in 3 months old infants. The p,p′-DDE/p,p′-DDT ratio ranged from 1 to 23, where 58% of the mothers had a ratio below 5 indicating recent or ongoing DDT exposure.This study reports infant exposure and maternal body burden of organochlorines through breast milk. Although the findings give no reason to limit breast-feeding, it is essential to identify the main exposure sources and find means to decrease the exposure.  相似文献   
160.
A lake system in northern Saskatchewan receiving treated metal mine and mill effluent contains elevated levels of selenium (Se). An important step in the trophic transfer of Se is the bioaccumulation of Se by benthic invertebrates, especially primary consumers serving as a food source for higher trophic level organisms. Chironomids, ubiquitous components of many northern aquatic ecosystems, were sampled at lakes downstream of the milling operation and were found to contain Se concentrations ranging from 7 to 80 mg kg−1 dry weight. For comparison, laboratory-reared Chironomus dilutus were exposed to waterborne selenate, selenite, or seleno-DL-methionine under laboratory conditions at the average total Se concentrations found in lakes near the operation. Similarities in Se localization and speciation in laboratory and field chironomids were observed using synchrotron-based X-ray fluorescence (XRF) imaging and X-ray absorption spectroscopy (XAS). Selenium localized primarily in the head capsule, brain, salivary glands and gut lining, with organic Se species modeled as selenocystine and selenomethionine being the most abundant. Similarities between field chironomids and C. dilutus exposed in the laboratory to waterborne selenomethionine suggest that selenomethionine-like species are most readily accumulated, whether from diet or water.  相似文献   
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