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排序方式: 共有1055条查询结果,搜索用时 15 毫秒
101.
Francesca R. Grati Denise Molina Gomes Devika Ganesamoorthy Livia Marcato Simona De Toffol Eleonore Blondeel Francesca Malvestiti Laurence Loeuillet Anna Maria Ruggeri Robert Wainer Federico Maggi Azzedine Aboura Celine Dupont Anne Claude Tabet Fabien Guimiot Howard R. Slater Giuseppe Simoni François Vialard 《黑龙江环境通报》2013,33(1):32-41
102.
Rosalind Aughwane Emma Ingram Edward D. Johnstone Laurent J. Salomon Anna L. David Andrew Melbourne 《黑龙江环境通报》2020,40(1):38-48
Objective
Magnetic resonance imaging (MRI) of placental invasion has been part of clinical practice for many years. The possibility of being better able to assess placental vascularization and function using MRI has multiple potential applications. This review summarises up-to-date research on placental function using different MRI modalities.Method
We discuss how combinations of these MRI techniques have much to contribute to fetal conditions amenable for therapy such as singletons at high risk for fetal growth restriction (FGR) and monochorionic twin pregnancies for planning surgery and counselling for selective growth restriction and transfusion conditions.Results
The whole placenta can easily be visualized on MRI, with a clear boundary against the amniotic fluid, and a less clear placental-uterine boundary. Contrasts such as diffusion weighted imaging, relaxometry, blood oxygenation level dependent MRI and flow and metabolite measurement by dynamic contrast enhanced MRI, arterial spin labeling, or spectroscopic techniques are contributing to our wider understanding of placental function.Conclusion
The future of placental MRI is exciting, with the increasing availability of multiple contrasts and new models that will boost the capability of MRI to measure oxygen saturation and placental exchange, enabling examination of placental function in complicated pregnancies. 相似文献103.
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Francesca R. Grati Francesca Malvestiti Beatrice Grimi Elisa Gaetani Anna Maria Di Meco Anna Trotta Rosaria Liuti Sara Chinetti Francesca Dulcetti Anna Maria Ruggeri Cristina Agrati Giuditta Frascoli Silvia Milani Simona De Toffol Lorenza Martinoni Silvia Paganini Livia Marcato Federico Maggi Giuseppe Simoni 《黑龙江环境通报》2013,33(5):502-508
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Effects of Population Size and Food Stress on Fitness-Related Characters in the Scarce Heath, a Rare Butterfly in Western Europe 总被引:6,自引:0,他引:6
Abstract: Knowledge about the effects of inbreeding in natural populations is scarce, especially in invertebrates. We analyzed to what extent fitness-related traits in the scarce heath ( Coenonympha hero ), a butterfly, are affected by population size and isolation and whether differences in food quality influence these effects. We categorized nine populations as either large or small and isolated. Full-sib groups of offspring from 27 females were followed under seminatural conditions. Because of increased zygote mortality, egg hatchability was significantly lower in the small and isolated populations than in the large ones. Population category had no effect on larval weight under optimal conditions, but weight was significantly lower in the small-isolated category with low food quality. The effects of inbreeding can thus be hidden when conditions are benign but can appear under stress. Survival also differed significantly between population categories, and larval developmental time tended to be longer in the small-isolated category, irrespective of food conditions. We suggest that the differences in fitness between offspring from large and small isolated populations are at least partly due to inbreeding. This adds a further threat to a species that is already suffering from decreasing population sizes and increasing isolation among populations. 相似文献