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The amounts of total NH 4 + detected in the external media in which Phascolosoma arcuatum had been exposed to various periods of anoxia were significantly greater than those in which the worms were exposed to normoxia for a similar period. The increased NH 4 + production by P. arcuatum during anoxic exposure was unlikely to be due to an increased catabolism of adenine nucleotides or urea. In contrast, there were significant decreases in the concentrations of several free amino acids in the coelomic plasma and body tissues of individuals during the 48 h of anoxic exposure. The amount of NH 4 + produced by the anoxic P. arcuatum could be accounted for by the decreases in the concentrations of aspartate or glycine. Increases in the catabolism of free amino acids (FAA), leading to the increased production of NH 4 + , in P. arcuatum during anoxia were supported by the detection of significant changes in the kinetic properties of glutamate dehydrogenase (GDH), in the deaminating direction, from worms exposed to anoxia for 48 h. The apparent increase in the affinity of GDH from the anoxic worm to glutamate would bring about a greater deaminating activity at physiological concentrations of ths substrate. P. arcuatum used in these experiments were collected from the mangrove swamp at Mandai, Singapore between 1990 and 1993.  相似文献   
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Three monoclonal antibodies (MAbs) against trophoblast (GB17, GB21, and GB25) and flow cytometry were used to sort trophoblast-like cells (TLCs) from peripheral blood of pregnant women. Sorted TLCs were processed for electron microscopy and fetal DNA amplification of the Y-specific sequences from mothers carrying male fetuses. At the ultra-structural level, most of the nucleated cells had the morphology of leucocytes, suggesting maternal contaminants, and we did not find the characteristic features of the free inter-villous trophoblast cells. Nevertheless, polymerase chain reaction (PCR) analysis showed an amplification of Y-specific sequences in two out of three samples of sorted TLCs. These results suggest that besides the maternal leucocytes, sufficient trophoblast nucleated fetal cells can be obtained using cell enrichment by sorting. This sensitive method holds promise for non-invasive prenatal diagnosis of fetal sex and if sufficient Y(positive) nuclei are found, for the diagnosis of selected numerical chromosome abnormalities.  相似文献   
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Study on Assessing Economic Vulnerability of Small Island Regions   总被引:2,自引:0,他引:2  
The main purpose of this study is to assess economic vulnerability of small island development regions as part of their sustainability constraints. By combining economic and environmental time series data, we assessed a composite index of economic vulnerability which is constructed from three exogenous variables, namely economic exposure, economic remoteness, and economic impact of environmental and natural disasters. We used the Amami Islands, Kagoshima Prefecture, Japan as the case studies for this paper.The results indicated that using a gross island products based valuation index, Kikaijima is the most vulnerable island in the Amami Islands with a composite economic vulnerability index (CEVI) value of 0.678, while by using a per capita based index, Okinoerabujima is considered the most vulnerable island with a CEVI value of 0.680. From the results we also revealed that smaller islands have relative higher vulnerability than the bigger one, which also confirms some previous country-level vulnerability studies.However, it is matter of fact that some islands that have relatively high vulnerability also have good economic performance as shown by their per capita income. In this regard, it can be argued that the success of these small islands could have been achieved in spite of and not because of their inherent vulnerability conditions as an indicator of sustainability constraint. Regarding these findings, we also examined a comparison between vulnerability results and the preliminary concept of an island's resilience in order to capture another perspective on sustainability assessment in a small island region.  相似文献   
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5p deletion syndrome commonly known as cri du chat is well described in affected neonates with catlike cry and hypotonia. Karyotyping will usually show a deletion of the short arm of one chromosome 5 with variable breakpoints. Only a few cases have been reported prenatally, and the fetal form of the syndrome has not been clearly individualised. We report a new case of 5p deletion syndrome diagnosed prenatally in association with Dandy–Walker syndrome and agenesis of the corpus callosum. Other brain anomalies have been reported previously, but this unusual association suggests the use of a specific probe in the investigation of these malformations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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为了实现建筑行业的可持续发展,设计并实现绿色环保节能建筑,将节能环保理念渗透在建筑设计的每个细节中。分析融入节能环保理念的建筑设计过程,对其中的架构环保节能设计、节能环保材料的选用以及节能环保技术发展进行研究,并重点分析了资源可持续利用、太阳能利用以及电气节能技术在绿色环保节能建筑设计中的应用过程。通过绿色建筑节能环保总设计,绿色节能环保建筑构造的优化设计以及绿色建筑的暖通空调设计,实现绿色环保节能建筑的高质量设计。  相似文献   
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