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141.
Abstract

The aim of the research was to evaluate the effect of consumption of selenium-enriched pork on selected health indicators of probands. The intake of feed mixture with increased organic selenium at the dose of 0.3?mg.kg?1 probably increases selenium concentration in MSM (musculus semimembranosus). In the pork enriched with organic selenium, the concentration was higher by 1.045?±?0.10?mg.kg?1 compared with the control group 0.701?±?0.05?mg.kg?1 at significance P?<?0.001. Sixteen participants in the experiment were represented by 8 men at the average age of 41.5?±?11.9?years and 8 women at the average age of 41.4?±?7.9?years. All the probands consumed meat enriched with selenium three times a week during one month. By consumption of the enriched pork, there was an increase of the selenium concentration in blood serum of probands traced with selenium increase from 73.19?±?15.68?μg.L?1 to 73.73?±?15.13?μg.L?1 (P?>?0.05). From the results we can see that consumption of enriched pork with selenium was significantly manifested in lowering of total cholesterol levels, which was associated with LDL cholesterol lowering (P?<?0.05). Differences among the HDL cholesterol and triglycerides samples were not significant.  相似文献   
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143.
We report an unusual case involving chorionic villus sampling (CVS) and trisomy 8 mosaicism. CVS showed a normal direct preparation while the culture showed mosaicism for trisomy 8. Subsequent amniocentesis revealed only normal chromosomes. A peripheral blood culture after birth revealed low-level trisomy 8 mosaicism. The patient appeared phenotypically and developmentally normal at 30 months of age. We conclude that prenatal counselling for similar cases needs to include the rare but real possibility that chromosome mosaicism detected prenatally may be found postnatally with largely unknown consequences. Secondly, low-level chromosomal mosaicism may be more common than previously recognized. Thirdly, very low-level trisomy 8 mosaicism may be compatible with a normal phenotype but long-term follow-up is required. And lastly, the use of fetal blood sampling is questionable in these cases because the phenotype may not be accurately predicted. Further studies of such cases are needed to address these important and unanswered issues, including the potential implication of mosaicism on academic performance and cognitive functioning.  相似文献   
144.
Shoreline is one of the rapidly changing linear features of the coastal zone which is dynamic in nature. The issue of shoreline changes due to sea level rise over the next century has increasingly become a major social, economic and environmental concern to a large number of countries along the coast, where it poses a serious problem to the environment and human settlements. As a consequence, some coastal scientists have advocated analyzing and predicting coastal changes on a more local scale. The present study demonstrates the potential of remote sensing, geospatial and statistical techniques for monitoring the shoreline changes and sea level rise along Digha coast, the eastern India. In the present study, multi-resolution and multi temporal satellite images of Landsat have been utilized to demarcate shoreline positions during 1972, 1980, 1990, 2000, and 2010. The statistical techniques, linear regression, end-point rate and regression coefficient (R2) have been used to find out the shoreline change rates and sea level change during the periods of 1972–2010. Monthly and annual mean sea level data for three nearby station viz., Haldia, Paradip and Gangra from 1972 to 2006 have been used to this study. Finally, an attempt has been made to find out interactive relationship between the sea level rise and shoreline change of the study area. The results of the present study show that combined use of satellite imagery, sea level data and statistical methods can be a reliable method in correlating shoreline changes with sea level rise.  相似文献   
145.
Environmental Science and Pollution Research - The North Bohemian Brown Coal Basin (Czech Republic) is suggested as a source of significant pollution in the surrounding environment with various...  相似文献   
146.
Particulate matter less than 2.5 microns in diameter (PM(2.5)) has been linked with a wide range of adverse health effects. Determination of the sources of PM(2.5) most responsible for these health effects could lead to improved understanding of the mechanisms of such effects and more targeted regulation. This has provided the impetus for the Denver Aerosol Sources and Health (DASH) study, a multi-year source apportionment and health effects study relying on detailed inorganic and organic PM(2.5) speciation measurements.In this study, PM(2.5) source apportionment is performed by coupling positive matrix factorization (PMF) with daily speciated PM(2.5) measurements including inorganic ions, elemental carbon (EC) and organic carbon (OC), and organic molecular markers. A qualitative comparison is made between two models, PMF2 and ME2, commonly used for solving the PMF problem. Many previous studies have incorporated chemical mass balance (CMB) for organic molecular marker source apportionment on limited data sets, but the DASH data set is large enough to use multivariate factor analysis techniques such as PMF.Sensitivity of the PMF2 and ME2 models to the selection of speciated PM(2.5) components and model input parameters was investigated in depth. A combination of diagnostics was used to select an optimum, 7-factor model using one complete year of daily data with pointwise measurement uncertainties. The factors included 1) a wintertime/methoxyphenol factor, 2) an EC/sterane factor, 3) a nitrate/polycyclic aromatic hydrocarbon (PAH) factor, 4) a summertime/selective aliphatic factor, 5) an n-alkane factor, 6) a middle oxygenated PAH/alkanoic acid factor and 7) an inorganic ion factor. These seven factors were qualitatively linked with known PM(2.5) emission sources with varying degrees of confidence. Mass apportionment using the 7-factor model revealed the contribution of each factor to the mass of OC, EC, nitrate and sulfate. On an annual basis, the majority of OC and EC mass was associated with the summertime/selective aliphatic factor and the EC/sterane factor, respectively, while nitrate and sulfate mass were both dominated by the inorganic ion factor. This apportionment was found to vary substantially by season. Several of the factors identified in this study agree well with similar assessments conducted in St. Louis, MO and Pittsburgh, PA using PMF and organic molecular markers.  相似文献   
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148.
Regional Environmental Change - Integrated farming systems (IS) are one of the main strategies of the Brazilian government to reduce or compensate for carbon emissions from agriculture with...  相似文献   
149.
The present study was designed to reveal whether long-term consumption of bitter apricot seeds causes changes in lipid profile and other risk factors for cardiovascular diseases. The study group consisted of 12 healthy adult volunteers (5 females and 7 males). The average age of women was 41.60 ± 11.28 years and the average age of men was 36.71 ± 13.70 years. Volunteers consumed 60 mg kg?1 of body weight of bitter apricot seeds divided into 8–12 doses daily for 12 weeks. Volunteers were recruited from the general population of Slovak Republic. After 12 weeks, mean body weight of the participants increased from 77.34 to 78.22 kg (P > 0.05). The average total cholesterol levels decreased from 4.86 mmol L?1 at the beginning of the study to 4.44 mmol L?1 at the end of the study (P < 0.05). We did not observe any significant increase in high-density cholesterol (from 1.55 to 1.60 mmol L?1). The average low-density cholesterol levels decreased from 2.93 mmol L?1 at the beginning of the study to 2.31 mmol L?1 at the end of the study (P < 0.001). Concentration of triglycerides increased significantly over the 12-week intervention period from 0.84 to 1.17 mmol L?1. After the intervention, the high-sensitivity C-reactive protein level decreased from 1.92 to 1.23 mg L?1, but results were non-significant (P > 0.05). Creatine kinase serum levels increased from 2.31 to 2.77 mg L?1 (P > 0.05) over the 12-week intervention period. The results suggest that regular intake of bitter apricot seeds may be considered potentially useful for prevention of cardiovascular diseases.  相似文献   
150.
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