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排序方式: 共有194条查询结果,搜索用时 703 毫秒
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Roni Zemet Inna Amdur-Zilberfarb Moran Shapira Tomer Ziv-Baran Chen Hoffmann Eran Kassif Eldad Katorza 《黑龙江环境通报》2020,40(1):142-150
Objectives
The aim of this study was to evaluate the role of fetal magnetic resonance imaging (MRI) as a complement to ultrasound (US) in the prenatal diagnosis of craniofacial anomalies.Methods
A historical cohort study including all pregnant women who were referred for fetal MRI because of antenatal diagnosis of craniofacial anomalies on screening US. Prenatal diagnostic US, MRI, and postnatal diagnosis were compared for consistencies and discrepancies.Results
Forty-five pregnant women with 73 suspected fetal craniofacial anomalies diagnosed by US underwent MRI. In 40 out of 73 anomalies (54.8%), US and MRI findings were in complete agreement with postnatal diagnoses. MRI correctly ruled out the diagnosis of 24 anomalies suspected on US and diagnosed four additional pathologies that were not demonstrated by US. Out of the 85 anomalies (suspected by imaging or confirmed postnatally), confident diagnosis could be made by MRI in 68 anomalies (80%), not diagnosed in 10 (11.8%), and over-diagnosed in seven (8.2%). By US, confident diagnosis could be made in 44 anomalies (51.8%), not diagnosed in 11 (12.9%), and over-diagnosed in 30 (35.3%).Conclusion
MRI is valuable in the antenatal evaluation of fetal craniofacial anomalies and may be useful as an adjunct to US in the prenatal work-up of craniofacial anomalies. 相似文献25.
The difference conservation makes to extinction risk of the world's ungulates 总被引:1,自引:0,他引:1 下载免费PDF全文
Michael Hoffmann J.W. Duckworth Katharine Holmes David P. Mallon Ana S.L. Rodrigues Simon N. Stuart 《Conservation biology》2015,29(5):1303-1313
Previous studies show that conservation actions have prevented extinctions, recovered populations, and reduced declining trends in global biodiversity. However, all studies to date have substantially underestimated the difference conservation action makes because they failed to account fully for what would have happened in the absence thereof. We undertook a scenario‐based thought experiment to better quantify the effect conservation actions have had on the extinction risk of the world's 235 recognized ungulate species. We did so by comparing species’ observed conservation status in 2008 with their estimated status under counterfactual scenarios in which conservation efforts ceased in 1996. We estimated that without conservation at least 148 species would have deteriorated by one International Union for Conservation of Nature (IUCN) Red List category, including 6 species that now would be listed as extinct or extinct in the wild. The overall decline in the conservation status of ungulates would have been nearly 8 times worse than observed. This trend would have been greater still if not for conservation on private lands. While some species have benefited from highly targeted interventions, such as reintroduction, most benefited collaterally from conservation such as habitat protection. We found that the difference conservation action makes to the conservation status of the world's ungulate species is likely to be higher than previously estimated. Increased, and sustained, investment could help achieve further improvements. 相似文献
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Pinealectomy and photoperiod influence testicular development in the djungarian hamster 总被引:1,自引:0,他引:1
The Science of Nature - 相似文献
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Sam Provoost Carole Ampe Dries Bonte Eric Cosyns Maurice Hoffmann 《Journal of Coastal Conservation》2004,10(1):33-42
Grey dunes are a priority habitat type of the European Union Habitats Directive and demand special attention for conservation
and management. Knowledge of the ecology of coastal grey dunes can contribute to this policy. Dune grassland succession is
initiated by fixation and driven by the complex of soil formation (humus accumulation) and vegetation development. Leaching
and mobilization of CaCO3. which are important in nutrient dynamics, complicate the picture. At present, grass- and scrub encroachment greatly overrules
these fine scaled soil processes and causes substantial loss of regional biodiversity. Belgium has an international responsibility
in grey dune conservation because of the limited range of its characteristic vegetation, flora and fauna. As biomass removal
seems essential in grassland preservation, grazing is an important management tool. Evaluation of management measures focuses
on biodiversity measurements on the levels of landscape, community and species. 相似文献