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911.
Intestinal disaccharidases in amniotic fluid were studied in 41 pregnancies with a recurrence risk for cystic fibrosis (CF). In 11 out of 13 pregnancies with CF fetuses the maltase and sucrase activities were either below the control range (8 cases) or below the 10th percentile of control values (3 cases). Trehalase and lactase were slightly less informative indicators of CF. Of the other 28 pregnancies 3 had low amniotic fluid activities of several intestinal enzymes and were terminated, 12 resulted in the birth of a healthy child and 13 are continuing. The findings in fetal CF suggest an impairment of the defaecation of intestinal contents into the amniotic fluid. Reduced or low amniotic fluid disaccharidase activities were also found in other fetal disorders with demonstrated or presumed intestinal anomalies: e.g. anal atresia (2 cases), anencephaly (3 our of the 7 cases), trisomy 13 (5 cases), trisomy 18 (3 of the 5 cases) and trisomy 21 (19 of the 22 cases). Reduced amniotic fluid disaccharidase activities, although not specific for CF, are highly informative in pregnancies at high risk for CF. Using the 10th percentile of the normal range for amniotic fluid disaccharidase activities as an action line, the sensitivity of CF detection is estimated at 80 to 90 per cent, which could in high risk pregnancies reduce the risk of having another affected child from 1 in 4 to 1 in 20. 相似文献
912.
Diane Van Opstal Geerke M. Eggenhuizen Marieke Joosten Karin Diderich Lutgarde Govaerts Robert-Jan Galjaard Attie Go Maarten Knapen Marjan Boter Wai Y. Cheung Nicole van Koetsveld Stefanie van Veen Walter G. de Valk Fernanda Jehee Femke de Vries Iris Hollink Lies Hoefsloot Malgorzata Srebniak 《黑龙江环境通报》2020,40(10):1338-1342
913.
914.
915.
Paolo Ciavola Oscar Ferreira Piet Haerens Mark Van Koningsveld Clara Armaroli Quentin LequeuxAuthor vitae 《Environmental Science & Policy》2011,14(7):912-923
The current paper discusses the topic of marine storm impact along European coastlines, presenting results from two FP7 Projects currently focusing on this topic, one working on the physical aspects of the problem (MICORE) and the other one on the socio-economic implications (ConHaz).The MICORE Project aims to provide on-line predictions of storm-related physical hazards (hydrodynamic as well as morphodynamic). The ConHaz Project addresses the socio-economic implications should these (or other) hazards actually materialize. Together these projects aim to deliver crucial information for emergency response efforts, while realizing the practical limitations for information processing and dissemination during crisis situations.The MICORE Project has developed and demonstrated on-line tools for reliable predictions of the morphological impact of marine storm events in support of civil protection mitigation strategies. The project specifically targeted the development of early warning and information systems to support short term emergency response in case of an extreme storm event. The current paper discusses in detail the outcome of an activity of databasing historical storm data. No clear changes in storminess were observed, except for some storm proxies (e.g. surges) and only at some locations (e.g. northern Adriatic, southern Baltic, etc.).The ConHaz Project undertook a desktop study of the methods normally used for evaluating the impact of marine storms and the associated coastal hazards considering direct costs, costs due to disruption of production processes, indirect costs, intangible costs, and costs of adaptation and mitigation measures. Several methods for cost estimation were reviewed. From the review it emerged that normally end-users only evaluate direct costs after the storms, while the cost of adaptation and mitigation measures is only done strategically in the context of Integrated Coastal Zone Management plans. As there is no standardized method for cost evaluations in this field, it is suggested that clear guidelines should be produced on the basis of simplicity for use by end-users. The integration between historical databases of the physical parameters of storms and detailed cost evaluation information would support the development of a knowledge background in end-users and justify the development of adaptation strategies. 相似文献
916.
Maria Neofytou Nathalie Brison Kris Van den Bogaert Luc Dehaspe Koen Devriendt Anja Geerts Joris R. Vermeesch 《黑龙江环境通报》2018,38(2):148-150
Noninvasive prenatal testing (NIPT) can very accurately determine fetal sex during pregnancy. We present an exceptional case where NIPT contradicts the ultrasound-based sex determination. The pregnant woman was recipient of a liver transplant from a male donor. Graft-derived cell-free DNA released into the maternal circulation clouded the NIPT-based sex determination. Hence, NIPT is not advisable when the pregnant mother underwent an organ transplant. 相似文献
917.
A fetal goitre is a potentially dangerous phenomenon because of mechanical obstruction and possible fetal thyroid function disorders. In this report we describe a patient with Graves' disease diagnosed in early pregnancy and treated with propylthiouracil, which resulted in a large fetal goitre and fetal hypothyroidism. The diagnostic problems are discussed and we focus on the need for fetal thyroid hormone serum evaluation. The only reliable way to obtain information about the fetal thyroid status is percutaneous fetal umbilical cord blood sampling, since amniotic fluid levels do not properly represent the fetal thyroid function. Fetal hypothyroidism can thus be diagnosed in utero and treated with intra-amniotic injections of thyroxine. The recommended dose and frequency of injections are only based on a few case reports and for that reason we performed a second fetal blood sampling 1 week later to evaluate our therapy. Weekly intra-amniotic injections of 250 μg of thyroxine seem to be sufficient to reduce a fetal goitre and give a normal thyroid hormone level. 相似文献
918.
随着新的教育、教学技术的不断涌现和新的教学模式的提出,传统的实验教学模式已经不能满足现代素质教育的要求,急需新的更为先进的教学模式来提高实验教学的效果。在此背景下,笔者通过研究探究式教学模式,并将此模式应用到大学物理实验教学中,取得了良好的效果。 相似文献
919.
Hanneke J. M. Meijer Arike Gill Perry G. B. de Louw Lars W. Van Den Hoek Ostende Julian P. Hume Kenneth F. Rijsdijk 《Die Naturwissenschaften》2012,99(3):177-184
Since 2005, excavations at Mare aux Songes, Mauritius, have revealed the presence of a very rich, ∼4,200-year-old fossil bone
bed including dodo (Raphus cucullatus) bones and bone fragments. The recently excavated dodo assemblage comprises at least 17 individuals and is characterised
by the presence of small and fragile skeletal elements, a dominance of leg elements and an absence of juveniles. The hydrology
of the area suggests that dodos, like many other species, were probably lured to Mare aux Songes by the presence of freshwater
during times of drought. The most likely scenario for the origin of the fossil deposit is that animals became trapped in the
sediment in repeated miring events, which would favour the conservation of hindlimbs. Such a scenario is fully in accordance
with the taphonomic characteristics of the bone assemblage. 相似文献
920.
N. Van Cauwenbergh K. Biala C. Bielders V. Brouckaert L. Franchois V. Garcia Cidad M. Hermy E. Mathijs B. Muys J. Reijnders X. Sauvenier J. Valckx M. Vanclooster B. Van der Veken E. Wauters A. Peeters 《Agriculture, ecosystems & environment》2007,120(2-4):229-242
Sustainable development and the definition of indicators to assess progress towards sustainability have become a high priority in scientific research and on policy agendas. In this paper, we propose a consistent and comprehensive framework of principles, criteria and indicators (PC&I) for sustainability assessment of agricultural systems, referred to as the Sustainability Assessment of Farming and the Environment (SAFE) framework. In addition we formulate consistent and objective approaches for indicator identification and selection. The framework is designed for three spatial levels: the parcel level, the farm level and a higher spatial level that can be the landscape, the region or the state. The SAFE framework is hierarchical as it is composed of principles, criteria, indicators and reference values in a structured way. Principles are related to the multiple functions of the agro-ecosystem, which go clearly beyond the production function alone. The multifunctional character of the agro-ecosystem encompasses the three pillars of sustainability: the environmental, economic and social pillars. Indicators and reference values are the end-products of the framework. They are the operational tools that are used for evaluating the sustainability of the agro-ecosystems. The proposed analytical framework is not intended to find a common solution for sustainability in agriculture as a whole, but to serve as an assessment tool for the identification, the development and the evaluation of agricultural production systems, techniques and policies. 相似文献