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71.
The sirenomelia sequence with fusion, rotation, hypotrophy or atrophy of the lower limbs in combination with severe urogenital and gastrointestinal malformations is a rare and usually lethal disorder. We present the case of a 28-year-old woman, who was referred to our department because of an intraabdominal cystic structure in the 9th week of gestation. Subsequent scans confirmed the diagnosis of a sirenomelia sequence with the fusion of the lower extremities without fusion of the bones according to Stocker I classification. The size of the intraabdominal cyst decreased during follow-up. After counseling, termination of pregnancy was induced. The postmortem X-ray confirmed the ultrasound diagnosis. The exact etiological mechanism of this malformation is still unknown. An early alteration of the embryological vascular network damaging the caudal mesoderm is thought to lead to arrested development of the lower limbs and other affected organs. The cyst we saw in the 9th week might fit with this theory, either as an expression of the complex malformation of the lower abdomen or as the sonographic appearance of necrosis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Hochwasser 2002     
In August 2002, highly contaminated areas in the region of Bitterfeld, e.g. the floodplain of the creek Spittelwasser, as well as the adjacent regions of Jeßnitz and Raguhn, were submerged by the river Mulde. An input of mobilized contaminated sediments in residential areas was the matter of concern. The objective of the present study was to estimate the pollutants load on the basis of chemical and biological data and identify the sources of pollutants. Deposited sludge and flood water samples were assessed on the basis of biological and chemical analyses and in comparison with administrative reference values. The pollution of the investigated sites was rather heterogeneous. At several sites, tolerance limits of the German Klärschlammverordnung or the Bundesbodenschutzverordnung were clearly exceeded, e.g. for Pb, As and HCH. Organic extracts exhibited significant effects in several biotests. This may be relevant with respect to direct particle uptake via ingestion or respiration. Pollution patterns for heavy metals as well as for organic pollutants differed significantly from the pattern found in the Spittelwasser flood plain before the inundation, which is in contrast to the initial hypothesis of a possible transport of contaminated Spittelwasser sediments into residential areas. Interestingly, a correlation of chemical load and the overall biological effect could be shown. From the viewpoint of the precautionary principle, the identification of the compounds exerting toxic effects and of the respective pollutant sources would be desirable.  相似文献   
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Environment, Development and Sustainability - Our aim is to determine the factors influencing a visitor’s decision to stay in a green accommodation facility. Visitors from six tourist sites...  相似文献   
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Ecological theory predicts that low productivity systems should have low biodiversity. However, despite the oligotrophic status of the Gulf of Aqaba (Northern Red Sea) ciliate species richness was unexpectedly high. In addition, phytoplankton, as main ciliate prey, was made up by only few genera, indicating a significant niche overlap among the grazers. Up to 97% of the ciliates were from the same taxonomic group and of the same size range, implying very similar food niches. Ciliate diversity was highest at times of lowest chlorophyll concentrations, during the period of stable abiotic conditions, but relatively high genetic diversity within the ciliate prey, notably among the cyanobacteria Synechococcus and Prochlorococcus. In the absence of disturbance and with little predation pressure, the alternate explanations for the observed ciliate diversity are either very fine niche partitioning by the ciliates, or their competitive equivalence resulting in a random assortment of species immigrating from a larger metacommunity, in accordance with Hubbell’s, (The unified neutral theory of biodiversity and biogeography. Princeton University Press, Princeton, 2001) neutral model. While the use of species abundance distributions (SAD’s) is far from definitive, the theoretical SAD’s that best fit the Gulf of Aqaba ciliate data was most often not that expected by neutral theory.  相似文献   
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Ziel und Hintergrund  

Seit Oktober 2003 liegt der Verordnungsentwurf zur Neuordnung der europ?ischen Chemikalienpolitik vor. Aus ihm ergeben sich zahlreiche, zum Teil neuartige Aufgaben für Hersteller und Importeure von Chemikalien, Zubereitungen und Erzeugnissen, für nachgeschaltete Anwender und für den Handel. Die Landesregierung Nordrhein-Westfalen hat in einem Pilotprojekt Schlüsselelemente des REACH-Systems in der Praxis erprobt. In dieser Ver?ffentlichung werden Erfahrungen aus dem Projekt aufgezeigt, die speziell für die Textilveredlung wichtig sind.  相似文献   
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Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential to maximizing AOM removal.However, the impact of AOM on the floc properties remains unclear. This study investigated how peptides/proteins derived from the cellular organic matter(COM) of the cyanobacterium Microcystis aeruginosa influenced the size, structure, and shape of flocs formed at different shear rates(G). Flocs formed by kaolinite, COM-peptides/proteins and a mixture of the same were studied, and the effect of intermolecular interactions between floc components on floc properties was assessed. The coagulation experiments were performed in a Taylor–Couette reactor, with aluminum(Al) or ferric sulphate(Fe) utilized as coagulants. Image analysis was performed to gauge floc size and obtain data on fractal dimension. It was found that floc properties were affected by the presence of the COM-peptides/proteins and the coagulant used. COM-peptides/proteins increased floc size and porosity and widened floc size distributions. The Fe coagulant produced larger and less compact flocs than Al coagulant. Moreover, the decrease in floc size that occurred in parallel with increase in shear rate was not smooth in progress. A rapid change for the kaolinite-coagulant suspension and two rapid changes for the suspensions containing COM were observed. These were attributed to various intermolecular interactions between floc components participating in coagulation at different G. Based on the results obtained, shear rates suitable for efficient separation of flocs containing COM were suggested.  相似文献   
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