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We report a new case of prenatal diagnosis of recessive microcephaly by ultrasound examination allowing termination of pregnancy at 25 weeks gestation.  相似文献   
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I. Ružić 《Marine Biology》1972,15(2):105-112
The interpretation of kinetics of radionuclide accumulation into biological organisms can be performed by using the well-known multicompartment models. The application of a two-compartment model in the interpretation of radionuclide accumulation into marine organisms, when this does not markedly deplete the medium, is considered. It has been found that most of the loss experiments cannot be interpreted without the use of uptake data. The agreement between the uptake and loss parameters is discussed. Explicit expressions for different kinds of two-compartment models are evaluated. The interpretation of irreversible and other special cases is proposed.  相似文献   
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Alluvial soils of valleys of the Danube and Mlave rivers represent priority development areas with favorable conditions for life, agriculture and tourism in eastern Serbia. Operation of the thermal power plant Kostolac results in the emission of potentially toxic pollutants into the air, water and land. The goals were to determine the soil pollution with inorganic pollutants using different pollution indices, to identify of the sources of pollutants by means of principal component analysis and the loading of each factor for individual element assessed by multi-linear regression analyses. Chemical characteristics of the studied area resulted in division of the area into four impact zones upon the distance from main pollutants (power plant blocks and ash disposal dumps). There was no established soil pollution with potentially toxic elements in bulk of the agricultural territory. Two principal components (PC1 and PC2) explained about 73% of variance. Three studied elements (As, Cu and Pb) showed anthropogenic origin of their most concentrations in soil, while other elements (Cd, Co, Cr, Ni and Zn) were of a natural (geological) origin. Single pollution index showed moderate pollution level by Ni. Integrated Nemerow pollution index showed low to no pollution levels, indicating slight ecological risk. There were no established limitations for agricultural production in the studied area, except for the only spot polluted by As due to the great flooding event in the studied year.

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The anthropogenic impact on the environment in the last century has proven to be very negative due to the fast development of industry. A typical example is the De?le River in northern France, one of the most polluted sites in this region. The concentrations of Pb, Cd, Zn and Cu in river sediments are 300, 800, 50 and 15 times higher, respectively, than the background values. The present study was undertaken to evaluate the capacity of already polluted sediments to capture metals released from industrial wastes (slag). As it were, in spite of the high metal pollution level, sediments have still shown the ability to adsorb metals released from slag under the conditions provided. Their efficiency in "cleaning up" some of the metals (e.g. Pb) seems to be additionally enhanced in anoxic conditions. This study provided some additional information on the importance of sediments as a pollutant sink.  相似文献   
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The measurement campaigns have been done in the rural community of Niska Banja, a spa town located in southern Serbia, to evaluate population exposure to natural radioactivity. After a screening survey in 200 houses, annual radon and thoron concentrations were measured in 34 houses, and in 2004 a detailed investigation was carried out at six houses with elevated indoor radon concentrations. The paper presents the results of these detailed measurements. The complementary techniques were applied to determine radon and thoron concentrations in indoor air, in soil gas, radon exhalation from soil, soil permeability, and indoor and outdoor gamma doses. Soil and water samples were collected and analysed in the laboratory. Indoor radon and thoron concentrations were found to be more than 1kBqm(-3) and 200Bqm(-3), respectively. Extremely high concentrations of soil-gas radon (>2000kBqm(-3)) and radon exhalation rates (1.5mBqm(-2)s(-1)) were observed. These results will be utilised to set up the methodology for a more systematic investigation.  相似文献   
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