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51.
A prenatally ascertained case with a de novo small supernumerary marker chromosome (sSMC) derived from chromosome 1 is reported. Due to a fetal heart defect the parents decided in favour of an induced abortion. Postmortem, a molecular cytogenetic study on eleven formalin fixed, paraffin-embedded tissues of the fetus was performed, to further characterize the levels of mosaicism of the sSMC(1). sSMC presence varied between 13 and 62% within different tissues of sSMC carriers. This finding is something common in sSMC carriers and could explain why up to the present no clinical correlations for sSMC mosaicism and clinical outcome in the corresponding carriers could be established. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
52.
The different methods of laser spectroscopy allow the detection of few atoms in a laser beam. There are several theoretical, physical limitations of atom detection. However, in normal extreme trace analysis, in most cases, several limitations arise due to contamination problems in sample handling and problems connected with sample atomization.  相似文献   
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54.
Hyperargininemia is a progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. We diagnosed arginase deficiency in a three-year-old male child of first-cousin Palestinian Arab parents. Prenatal diagnosis of an unaffected fetus was achieved in the second trimester of a subsequent pregnancy by cordocentesis and analysis of arginase activity in fetal erythrocytes. ARG1 mutation analysis in the proband revealed homozygosity for a deletion of 10 753 bp extending from the first intron to beyond the poly (A) site of the gene. This is the first gross deletion in the ARG1 gene to be identified and the first mutation to be described in an arginase-deficient patient of this ethnic origin. The identification of the ARG1 deletion in this family enabled first-trimester prenatal diagnosis in a subsequent pregnancy by multiplex PCR analysis performed on chorionic villous DNA. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
55.
Unique unaffected skeletal muscle fibres, unlike necrotic torso and limb muscles, may pave the way for a more detailed understanding of the molecular pathogenesis of inherited neuromuscular disorders and help to develop new treatment strategies for muscular dystrophies. The sparing of extraocular muscle in Duchenne muscular dystrophy is mostly attributed to the special protective properties of extremely fast-twitching small-diameter fibres, but here we show that distal muscles also represent a particular phenotype that is more resistant to necrosis. Immunoblot analysis of membranes isolated from the well established dystrophic animal model mdx shows that, in contrast to dystrophic limb muscles, the toe musculature exhibits an up-regulation of the autosomal dystrophin homologue utrophin and a concomitant rescue of dystrophin-associated glycoproteins. Thus distal mdx muscle groups provide a cellular system that naturally avoids myofibre degeneration which might be useful in the search for naturally occurring compensatory mechanisms in inherited skeletal muscle diseases.  相似文献   
56.
The degradation rate of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in silica-slurry systems to evaluate the bioavailability of sorbed-phase contaminant. After the silica particles were saturated with 2,4-D, the system was inoculated with the 2,4-D-degrading microorganism Flavorbacterium sp. strain FB4. The disappearance rate of 2,4-D was found to be greater than the rate predicted based upon liquid-phase 2,4-D concentrations. A kinetic formulation, termed the enhanced bioavailability model, was developed to describe the desorption and biodegradation processes in this batch system. The approach assumes that 2,4-D resides in both the liquid and solid phases and degradation occurs via both suspended and attached biomass. All biomass can degrade liquid-phase 2,4-D at one rate, while only attached biomass can degrade sorbed 2,4-D at another rate. An enhanced transformation factor (Ef) was introduced to express the increased biodegradation rate over that expected from the liquid phase only. This approach was able to account for the increased degradation rates observed experimentally. The results provide evidence that desorption to the bulk solution is not prerequisite to degradation, and that sorbed substrate may be available for degradation.  相似文献   
57.
We applied the Theory of Planned Behavior to help understand the relationships between environmental beliefs, support for ecosystem restoration actions, and willingness to pay (WTP) for restoration and protection goals in the Hudson River estuary, New York State, USA. We conducted a mail survey with 3,000 randomly-chosen local residents of the Hudson River estuary in the fall of 1999. As hypothesized, the broad ecosystem restoration goals of the Hudson River Estuary Action Plan were more strongly supported than the corresponding specific implementation actions. We found that beliefs and past behavior were better explanatory variables than sociodemographic characteristics for explaining people's support for ecosystem restoration actions and WTP for restoration and protection goals. Because ecosystem restoration goals appear to be more generally acceptable than specific restoration actions, proponents of restoration programs should not become complacent about the need for active public outreach and involvement even if initial restoration program discussions have been low in controversy. Efforts to assess and foster support for ecosystem restoration should be targeted toward audiences identified on the basis of beliefs and past behaviors rather than on sociodemographic characteristics.  相似文献   
58.
Meeting the demands of today's marketplace has become an increasingly complex challenge for corporations in all industries. The consumer is demanding high-quality products, low cost, and more recently, a new variable: environmental performance. Customers will not accept sacrifices in quality or cost to help businesses meet regulatory requirements or develop environmentally sound products. They want it all. Consequently, companies are faced with the complex task of balancing cost, quality, and environmental performance.  相似文献   
59.
The transfer of radioactive caesium from soils to plants has been well researched. In contrast there is limited knowledge on natural stable 133Cs and its potential role as a predictor for radiocaesium behaviour. In a pot experiment with Agrostis capillaris close correlations were found between plant 137Cs and plant 133Cs concentrations (R2 90-96%). Season and leaf age had significant effects with concentrations increasing 10-30-fold between June and December. Simultaneously the plant concentrations of K, the nutrient analogue of Cs, decreased to around one third. In the soil the exchangeable fractions of K and 137Cs declined. No clear relationships were found between 137+133Cs in the plant and exchangeable K in the soil. However, at the end of the experiment the K content of the above-ground biomass was higher than the exchangeable pool in the soil, suggesting that depletion of soil K could be a key factor in the observed increase of plant 137+133Cs over time.  相似文献   
60.
Larval dispersal is an important component of marine reserve networks. Two conceptually different approaches to incorporate dispersal connectivity into spatial planning of these networks exist, and it is an open question as to when either is most appropriate. Candidate reserve sites can be selected individually based on local properties of connectivity or on a spatial dependency-based approach of selecting clusters of strongly connected habitat patches. The first acts on individual sites, whereas the second acts on linked pairs of sites. We used a combination of larval dispersal simulations representing different seascapes and case studies of biophysical larval dispersal models in the Coral Triangle region and the province of Southeast Sulawesi, Indonesia, to compare the performance of these 2 methods in the spatial planning software Marxan. We explored the reserve design performance implications of different dispersal distances and patterns based on the equilibrium settlement of larvae in protected and unprotected areas. We further assessed different assumptions about metapopulation contributions from unprotected areas, including the case of 100% depletion and more moderate scenarios. The spatial dependency method was suitable when dispersal was limited, a high proportion of the area of interest was substantially degraded, or the target amount of habitat protected was low. Conversely, when subpopulations were well connected, the 100% depletion was relaxed, or more habitat was protected, protecting individual sites with high scores in metrics of connectivity was a better strategy. Spatial dependency methods generally produced more spatially clustered solutions with more benefits inside than outside reserves compared with site-based methods. Therefore, spatial dependency methods potentially provide better results for ecological persistence objectives over enhancing fisheries objectives, and vice versa. Different spatial prioritization methods of using connectivity are appropriate for different contexts, depending on dispersal characteristics, unprotected area contributions, habitat protection targets, and specific management objectives. Comparación entre los métodos de priorización de la conservación espacial con sitio y la conectividad espacial basada en la dependencia  相似文献   
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