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181.
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Sialic acid storage disorders, Salla disease (SD) and a severe infantile form of disease (ISSD), are recessively inherited allelic lysosomal storage disorders due to impaired egress of free sialic acid from lysosomes. Fourteen pregnancies at risk of adult-type free sialic acid storage disease, SD, were monitored by sialic acid assays, genetic linkage or mutation detection analyses using chorionic villus samples. Three affected and 12 unaffected fetuses were identified. The first studies were based on the sialic acid assays alone, but the location of the gene enabled the use of genetic linkage analysis and, more recently, the identification of the SLC17A5 gene and disease-causing mutations added yet another possibility for prenatal studies. A missense mutation 115C→T (R39C) is present in 95% of all Finnish SD alleles, providing an easy and reliable means of diagnostic studies. Both molecular and biochemical (sialic acid assay) studies can be used for prenatal diagnosis of free sialic acid storage diseases. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
183.
Stefano Regis Mirella Filocamo Raffaella Mazzotti Roberto Cusano Fabio Corsolini Gloria Bonuccelli Marina Stroppiano Rosanna Gatti 《黑龙江环境通报》2001,21(8):668-671
A prenatal diagnosis of Pelizaeus-Merzbacher disease (PMD) resulting from proteolipid protein gene (PLP) duplication was performed by a quantitative fluorescent multiplex PCR method. PLP gene copy number was determined in the proband, the pregnant mother, the male fetus and two aunts. Small amounts of genomic DNA extracted from peripheral blood and from chorionic villi were used. The fetus, in common with the proband, was identified as PMD-affected being a carrier of the PLP gene duplication, inherited from the mother, while the two aunts were non-carriers. The data obtained were confirmed by segregation analysis of a PLP-associated dinucleotide-repeat polymorphism amplified by the same multiplex PCR. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
184.
Matthew R. Auer 《Sustainability Science》2007,2(2):179-187
It has been nearly 20 years since a working definition for “sustainable development” was put forward by the World Commission
on Environment and Development. The concept endures in the mission statements and frameworks of action of various societal
actors, including those of neighborhood associations, metropolitan development authorities, environmental ministries, and
United Nations (UN) specialized organizations, to name a few. Yet many observers doubt that sustainable development is occurring
in poor countries. This failure, the critics contend, stems from miserly transfers of foreign aid. The extent to which inadequate
aid is to blame for poor environmental/developmental outcomes is an open question. But vocal demands for increasing aid to
meet sustainable development goals come from many parts of society and are persistent. Exhortations for more aid to help poor
countries are noble, perhaps even justifiable, but there are understandable doubts about the wisdom of transferring large
capital and technical resources to countries that are slow to adopt needed institutional reforms. Aid without institutional
reform is a recipe for wasted resources and donor fatigue. Worse, it may enhance inequities of wealth and power in recipient
countries. There are few illustrations to draw on demonstrating how institutionally impoverished societies are affected when
they are compelled to absorb massive aid inputs over a short period––a remedy suggested by some prominent aid experts. As
a proxy, it is valuable to examine instances where swift macroeconomic changes, spurred by external investment and export-led
growth, has occurred without significant institutional development. The case of Equatorial Guinea and its sudden oil riches
is examined to discern whether, in the absence of meaningful institutional reform, rapid and profound increases in foreign
direct investment and export income enable poverty alleviation and sustainable development.
相似文献
Matthew R. AuerEmail: |
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考察中国海洋三大经济圈海洋经济发展区域差异,探究其分布动态演进规律,识别其空间非均衡的影响因素及空间溢出效应,为“十四五”期间优化海洋经济发展空间布局、推动区域海洋经济协同均衡发展提供决策参考。利用Dagum基尼系数及其分解方法考察三大海洋经济圈海洋经济发展区域相对差异的程度、来源及演变态势,在此基础上,进一步应用Kernel密度估计方法刻画其绝对差异的分布动态演进过程,并将空间效应纳入研究框架,应用空间计量分析方法识别海洋经济发展空间非均衡的影响因素及空间溢出效应。研究发现:三大海洋经济圈海洋经济发展均呈现稳定上升态势,但三者之间存在显著的分级现象;三大海洋经济圈空间非均衡程度显著,超变密度是造成三大海洋经济圈整体区域差异的主要来源;三大海洋经济圈海洋经济发展水平“极化效应”显著,呈现不同极化特征和分布延展性;三大海洋经济圈海洋经济发展存在显著的空间依赖性,总体表现为空间正相关。 相似文献
188.
Since the early 1960s, many investigators have reported that blackfoot disease, a peripheral vascular disease, observed in southwestern Taiwan is due to drinking the higher arsenic concentration in well water. However, recent studies indicated that the relationship with blackfoot disease is not only with arsenic but also humic substances. This paper presents some results concerning the characterization (such as fluorescence, elemental composition, molecular weight and carbon distribution) of humic substances isolated from the Fuhsing well water of the blackfoot disease area. For comparison, the dissolved organic carbon (DOC) and humic substances in the normal well water from Chiuying and the Nanwan coastal water were also analyzed. In general, in the well water of the blackfoot disease area, extremely high concentrations of DOC (18.5mg/L) and fulvic acid (7.54mg/L) with high fluorescence intensity (59.1, equivalent to 0.0282uM quinine sulfate solution) and high percentages (over 50%) of low molecular weights of less than 1,000 were obtained compared with those of normal waters. C‐13 Nuclear magnetic resonance spectroscopy showed a high content (37.2%) of aromatic carbon. These higher concentrations of DOC and fulvic acid with the higher content of aromatic carbon in well water might be one of the key factors causing the blackfoot disease in Taiwan. 相似文献
189.
大骨节病区硒元素分布的调控机理研究——以四川省阿坝地区为例 总被引:5,自引:0,他引:5
分析了阿坝地区的岩石、饮用水、农作物及其根系土中硒的不同存在形态的分布,并结合生物有效性深入研究了硒元素分布与大骨节病病因的联系和调控机理.阿坝地区的环境(岩石、土壤、水)中全硒浓度、农作物中硒的富集系数和水溶性硒占总硒的含量均远低于非病区;硒在氧化还原条件(Eh平均值143.27 mV)和酸碱度(pH 6.51—8.48)的控制下主要以亚硒酸态的稳定形式存在.元素铝、铁等的富集可能会促进硒的沉淀和络合,制约硒的生物有效利用率,进而导致人体硒摄入不足,最终激发人类微小病毒B19(HPV B19)的毒性,引发大骨节病.通过采取土壤增施硒肥、改善水质、改变膳食结构等方法可以有效地提高环境中硒的水平及其生物有效性,以缓解大骨节病的病情及发病率. 相似文献
190.
Merideth Ferguson 《组织行为杂志》2012,33(4):571-588
This study examines the spillover and crossover effects of a specific chronic stressor, coworker incivility, on target marital satisfaction, partner marital satisfaction, and partner family‐to‐work conflict and on how the transmission of stress from the workplace to the family domain (as perceived by the target's partner) mediates these relationships. Using a matched data set of 190 job incumbents and their partners, the findings reveal that coworker incivility demonstrates both spillover and crossover effects on these outcomes important to the family. Evidence indicates that incivility targets do not leave the stress of incivility at work but instead bring it home to the family domain where it influences relationships with and outcomes of their partners. Implications of these findings and avenues for future research are discussed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献