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Different types of fetal nucleated cells can be found in maternal blood, providing the possibility of non-invasive prenatal diagnosis. For this purpose, we have studied fetal erythroblasts. We discovered that haemoglobin-containing cells treated with 2,3-bisphosphoglycerate (BPG) can be visualized by a peroxidase reaction, which at the same time visualizes an in situ hybridization (ISH) signal, specific for the X, Y or 21 chromosome. In order to prove that the BPG-positive cells were erythroid, an anti-glycophorin A (GPA) antiserum combined with a staphylococcal rosette technique was used. To enrich for erythroblasts, leukocytes were depleted from maternal blood by treatment with anti-CD45 monoclonal antibody and passage over an anti-mouse IgG-coated glass bead column. To evaluate the potential of the method for clinical use, we studied maternal blood samples from 18 women referred to us for prenatal diagnosis between 6 and 19 weeks of gestation. Erythroblasts were found in 13 out of 14 normal pregnancies. Erythroblasts with a Y-signal were found as early as 9 weeks of gestation, but at 6 weeks the Y-signal was seen in BPG-negative cells only. These cells showed an epithelioid morphology indicating that they were cytotrophoblasts. The BPG-ISH method provides a simple technique for identifying erythroblasts and simultaneously visualizing a desired probe. 相似文献
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Hansen DA Edgerton E Hartsell B Jansen J Burge H Koutrakis P Rogers C Suh H Chow J Zielinska B McMurry P Mulholland J Russell A Rasmussen R 《Journal of the Air & Waste Management Association (1995)》2006,56(10):1445-1458
Measurements of pollutant gases, airborne particulate matter mass and composition, and meteorology have been made at a core site near downtown Atlanta, GA, since August 1998 in support of the Aerosol Research and Inhalation Epidemiology Study (ARIES). This site is one of eight in the Southeastern Aerosol Research and Characterization network. The measurement objective is to provide a long-term, multivariate dataset suitable for investigating statistical associations of respiratory and cardiovascular disease with airborne particulate matter composition, meteorology, and copollutant gases through epidemiologic modeling. Measurements are expected to continue through 2010. Ancillary multiyear measurements at additional sites in the Atlanta metropolitan area and in short-term exposure assessments have been used to estimate the exposure/measurement error associated with using data from a central site to approximate human exposures for the entire area. To date, 13-, 25-, and 53-month air quality datasets have been used in epidemiologic analyses. 相似文献
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This paper examines the role of community-based management (CBM) in dealing with the problem of mine water pollution (MWP) in four ex-pit sites in northeast England. The outcomes of CBM can be divided into two categories: ecological (environmental improvement) and social (community improvement). The ecological outcomes range from problem recognition to investigation and remediation; the social outcomes range from community awareness to participation and enhanced cooperation. Both kinds of outcome were completely achieved in only one site (Quaking Houses). In the other three sites, varying degrees of success were achieved in each category. The main lessons learned are two-fold: first, even if CBM does not achieve its ecological aims, it may nonetheless be valuable in achieving social outcomes; second, its chances of achieving either ecological or social outcomes are linked to the resources (human, technical, financial, experiential, structural, legitimacy and network) that the community possesses. 相似文献
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David A. Ehlers Smith Yvette C. Ehlers Smith Harriet T. Davies-Mostert Lindy J. Thompson Daniel M. Parker Deon de Villiers Dean Ricketts Brent Coverdale Peter J. Roberts Christopher Kelly Duncan N. Macfadyen Nomthandazo S. Manqele R. John Power Colleen T. Downs 《Ambio》2023,52(3):598
Conservationists speculated on potential benefits to wildlife of lockdown restrictions because of the COVID-19 pandemic but voiced concern that restrictions impeded nature conservation. We assessed the effects of lockdown restrictions on biodiversity conservation in South Africa, a biodiverse country with economic inequality and reliance on wildlife resources. We solicited expert opinion using the IUCN’s Threats Classification Scheme to structure a questionnaire and illustrated responses with individual case studies from government parastatal and non-governmental conservation organisations. The most highly reported threats were biological resource use, residential/commercial developments, invasive species, and human intrusions. The trends reported by 90 survey respondents were supported by case studies using environmental compliance data from parastatal conservation organisations. Lack of tourism revenue and funding were cited as hindrances to conservation. Mechanisms to prevent environmental degradation in the face of global emergencies must be implemented and ‘ring-fenced’ to ensure conservation is not a casualty during future global crises.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01814-z. 相似文献
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Pirkko Ämmälä Vilho K. Hiilesmaa Sirkka Liukkonen Terhi Saisto Kari Teramo Harriet Von Koskull 《黑龙江环境通报》1993,13(10):919-927
A total of 800 patients were randomized at the 9th to 11th week of pregnancy either for transcervical chorionic villus sampling (CVS) on the day of trial entry or for amniocentesis (AC) at the 16th week. The indication for fetal karyotyping was maternal age in 94 per cent of the cases; the mean maternal age was 39.2 years. An adequate sample was obtained in 98.3 per cent of the cases in the CVS group and in all cases in the AC group. Retesting was indicated in 3.3 per cent of the CVS cases. An abnormal karyotype was found in 6.1 per cent of the CV samples and in 4.5 per cent of the amniotic fluid samples. There was one false-positive chromosome result in both groups. Twelve (3.1 per cent) miscarriages occurred by the 22nd week of pregnancy in the CVS group in pregnancies intended to continue. No difference was seen between the groups for total fetal loss rates. The number of surviving infants in the CVS group was 92.2 per cent and in the AC group 91.7 per cent (rate difference 0.5 per cent (95 per cent confidence interval − 3.3 to 4.3)). In our study, both the diagnostic accuracy and the risk of fetal loss were equal in the CVS and AC groups. 相似文献
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This paper introduces a special issue of Local Environment that has arisen through collaboration between academic researchers and the Urban Planning and Design Branch of UN-Habitat, focused on how we can understand and respond to the challenges of urban vulnerability, adaptation and resilience in the context of climate change. The paper establishes the existing state of the art in the field, and considers critical challenges that are emerging in the research-based literature. In this context, it introduces UN-Habitat's Cities and Climate Change Initiative and reflects on the lessons learnt and challenges ahead, drawing on insights from across the papers in the special issue. In conclusion, it identifies the role of international/transnational co-operation, the relation between adaptation and mitigation, issues of multi-level governance and the ways in which change in urban socio-technical systems might be achieved as critical issues across the science/policy interface where increased dialogue and the co-production of knowledge needs to focus in order to advance this agenda. 相似文献
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Sprawl, Smart Growth and Sustainability 总被引:4,自引:0,他引:4
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Hannu Anttonen Juhani Niskanen Harriet Meinander Volkmar Bartels Kalev Kuklane Randi E Reinertsen Sabine Varieras Krzysztof So?tyński 《International journal of occupational safety and ergonomics》2004,10(3):291-300
According to the European prestandard ENV 342:1998, the thermal insulation of cold-protective clothing is measured with a thermal manikin. Systematic studies on the reproducibility of the values, measured with different types of clothing on the commonly used standing and walking manikins, have not been reported in the literature. Over 300 measurements were done in 8 different European laboratories. The reproducibility of the thermal insulation test results was good. The coefficient of variation was lower than 8%. The measured clothing should fit the manikin precisely, because poorly fitting clothing gave an error in the results. The correlation between parallel and serial insulation values was excellent and parallel values were about 20% lower than serial ones. The influence of ambient conditions was critical only in the case of air velocity. The reproducibility of thermal insulation test results in a single laboratory was good, and the variation was lower than 3%. 相似文献