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Chorionic villus samples from a healthy pregnant female were obtained for first-trimester prenatal diagnosis. A translocation trisomy 21 was diagnosed. A consecutive amniocentesis revealed a normal male karyotype. At term a healthy boy was born. Cytogenetic analysis from cord blood showed a regular karyotype of 46,XY, whereas in term placenta a pathological karyotype of 47,XY,+mar was found.  相似文献   
104.
The results of a one-year monitoring program on the two Eastern Chinese River systems, i.e. the Liao-He and the Yangtse, with special emphasis on the presence of triazine herbicides are presented. Sediment, suspended solids and water samples from both rivers were analyzed. Additionally, recovery experiments on the SPE-in-field-enrichment procedure and the extraction methods were performed. The samples were measured by gas chromatography coupled with mass spectrometry, electron capture detection and a newly developed mu-plasma atomic emission detector. A typical result of a one-year monitoring was obtained in case of the Liao-He: During winter, at low water period, low triazine values were found. A similar situation was found in early spring. Highest concentrations of atrazine up to 1600 ng/l were found in late spring in the water samples. Maximum concentrations of atrazine, simazine, propazine, simetryn and prometryn were observed in this season as a result of the actual use of triazines. Finally, after the high water period in autumn the triazine concentrations decreased. Additionally, atrazine adsorbed on sediment (up to 2.8 ng/g) and suspended solids was determined (up to 8 ng/l) during late spring sampling. Therefore, the logarithm of the organic carbon based sorption coefficient of atrazine could be calculated. Low levels of atrazine were measured in the water of Yangtse (up to 18.3 ng/l). The concentrations from all sampling points and sampling stations of a particular sampling date were similar, which indicates a homogeneous distribution of this herbicide. Due to the high discharge rate of up to 79,000 m3/s in case of the Yangtse a considerable mass transport of up to 57.5 kg per day atrazine may take place, even at concentrations below the European drinking water limit of 100 ng/l.  相似文献   
105.
There are different methods to estimate and predict effects of chemical elements and corresponding speciation forms in biochemistry and toxicology, including statements on essentiality and antagonisms. Two approaches are given here: (1) "identity cards" describing biologically fundamental aspects of element chemistry and (2) qualitative discussions which assume the existence of (indirect ways into) chemical autocatalysis to be essential for maintaining life and permitting reproduction. The latter method, developed by the present authors, draws upon Stoichiometric Network Analysis, a safe procedure for complexity reduction in feedback networks) and provides estimates of concentration regimes for different elements suitable for survival and reproduction. The biochemical hierarchy level considered here is that of (metallo-)proteins. Thermodynamic toxicity aspects are given in correlations with DMSO solvent affinities and thiocyanate bonding modes. Effects of antagonists and of ion substitution within metalloenzymes or of metabolic simplification can be dealt with, likewise increased sensitivities within symbiotic relationships and within carcinomas are explained which are relevant for environmental monitoring and tumour therapy, respectively.  相似文献   
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BACKGROUND, AIM AND SCOPE: For decades, very large areas of former military sites have been contaminated diffusely with the persistent nitroaromatic explosive 2,4,6-trinitrotoluene (TNT). The recalcitrance of the environmental hazard TNT is to a great extent due to its particulate soil existence, which leads to slow but continuous leaching processes. Although improper handling during the manufacture of TNT seems to be a problem of the past in developed countries, environmental deposition of TNT and other explosives is still going on unfortunately, resulting from thousands of unexploded ordnance or low order explosions at munitions test areas and at current battlefields. OBJECTIVE: Sustainable phytoremediation strategies for explosives in Germany, which intend to use trees to decontaminate soil and groundwater ('dendroremediation'), have to consider that most of the former German military sites are already covered with woodlands, mainly with conifer stands. Therefore, parallel investigation of the remediation potential is necessary for both of the selected hybrids of fast growing broadleaf trees, which are waiting for planting and forest conifers, which have already proven for decades that they are able to grow on explosive contaminated sites. MAIN FEATURES: A short literature review is given regarding phytoremediation of TNT with herbaceous plants and some general aspects of dendroremediation are discussed. Furthermore, an overview of our TNT-dendroremediation research network is introduced, which has the strategic goal to make dendroremediation more calculable for a series of potent trees for site-adapted in situ application and for the assessment of tree remediation potentials in natural attenuation processes. RESULTS AND DISCUSSION: Some of our methods, results and conclusions yet unpublished are presented. For a preliminary calculation of area-related annual TNT dendroremediation potential of five-year-old trees, the following values were assessed: Salix EW-13 6.0, Salix EW-20 8.5, Populus ZP-007 4.2, Betula pendula 5.2, Picea abies 1.9 and Pinus sylvestris 0.8 g m(-2) a(-1). For a 45-year-old spruce forest, an annual natural attenuation potential of 4.2 g TNT m(-2) a(-1) was found. CONCLUSION, RECOMMENDATIONS AND PERSPECTIVE: Our main results deliver quantitative proposals for dendroremediation strategies in situ and provide decision aids. Also aspects of growth of raw materials for energy production are considered. Our dendroremediation research concept for TNT and its congeners can be easily completed for other trees of interest and it can also be applied to herbaceous plants. Knowing the current bottlenecks of phytoremediation and considering the known environmental behaviour of other contaminants, elements of our methodological approach may be easily adapted to those pollutant groups, e.g. for pesticides, pharmaceuticals, PAHs, chlorinated recalcitrants and, with some restrictions, to inorganics and to multiple contaminations. Our dynamical dendrotolerance test systems will help to predict tree growth on polluted areas. To provide some light into the black box of TNT dendroremediation, experimental data regarding the uptake, distribution and degradation of [14C]-TNT in mature tree tissues will be reported in the second part of this publication.  相似文献   
107.
This paper shows the geographic distribution in Germany of iron (Fe), nickel (Ni) and lead (Pb) analyzed in mosses in 1995/96 and compares it with the results of the 1990/91 pilot study within a European moss-monitoring programme. Other elements (As, Cd, Cr, Cu, Ti, V, Zn) are compared on basis of the overall element medians for Germany of the 1990/91 and 1995/96 survey. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupressiforme and Hylocomium splendens were taken at a total of 1026 sites. In the 1995/96 monitoring campaign, 95% of the original sites of the 1990/91 study were resampled. The results from 1995/96 display local elevated values and many cases of areas affected by known sources of heavy-metal emissions. The industrialized and urban regions of Germany are shown up clearly by the 1995/96 moss-monitoring results: the Ruhr area, parts of Saarland and Baden-Württemberg, as well as areas in eastern Germany. Relatively low values for many elements were found in large areas of Lower Saxony and Bavaria. A comparison of the results of the 1990/91 and 1995/96 moss-monitoring programmes shows a fall in the concentration of the presented elements (except cadmium, copper and zinc) over the relevant period. Especially in the former GDR, chromium (Cr), iron (Fe), titanium (Ti) and vanadium (V) decreased significantly. This is, firstly, a reflection of the closure of and/or technological improvements to large power plants; secondly it is due to the fact that lignite has given way to other fuels. Vanadium (V) and nickel (Ni), typical constituents of crude oil, also show a decrease in the western part and thus document changes in the type of fuel consumed. The significant fall in lead concentration in 1995/96 as compared to 1990/91 in what used to be East and West Germany probably results from the increasing use of lead-free petrol. A comparison of the median values for 1990/91 and 1995/96 in mosses to the rate of emission of heavy metals in Germany for 1990 and 1995 shows similar trends in the case of elements such as arsenic (As), chromium (Cr), nickel (Ni), and lead (Pb). The comparison of the medians of the elements analyzed for 19 European countries indicates for most of the elements a general tendency to lower values in 1995, except for Lithuania, Netherlands, Portugal, Italy and United Kingdom.  相似文献   
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The grey top-shell, Gibbula cineraria is a common member of temperate to cold water kelp forest communities, but its longevity and the age structure of its populations remains unresolved. Combined measurements of shell growth rates (sclerochronology) and oxygen isotope composition allow analysis of rate and timing of shell growth. Eight specimens were analyzed from the southern North Sea (near Helgoland, German Bight). Three age groups were identified but external measurements (width, height, ornamentation patterns and number of whorls) and shell weight are not adequate for ontogenetic age discrimination. Stable oxygen isotope data is consistent with shell growth during the interval from April to December in isotopic equilibrium with seawater, and growth increments exhibit strong tidal controls with fortnightly bundles well preserved. Reliable environmental proxy data (water temperature) can be extracted from the shell aragonite using conventional stable oxygen isotope analyses, with a temporal resolution of days attainable during intervals of maximum growth, but annual extremes are not always recorded in the shell. While demonstrating the utility of G. cineraria as a environmental and potential paleoenvironmental proxy for kelp forest habitats, its longevity has been significantly overestimated.  相似文献   
110.
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