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171.
Contents of mineral substance, silica, and a range of bioelements and toxic elements (Mg, Na, K, Ca, Ba, Zn, Cr, P Al, Cd, Mn Cu, Ni, Pb, Sr, Fe) in 38 livers of donors from the Upper Silesia Coal Basin (southern Poland) are presented. Elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) with the exception of silica that was estimated colorimetrically. Concentrations, concentration variability, and correlations between selected liver components determined for the total population are related to donor age, gender, and lesion occurrence. Correlations between particular elements were found using correlation coefficient values and the Fisher transformation. Mineral substance in the livers lies in the range 0.40–5.03 wt%. With increasing donor age, mineral-matter content decreases to a minimum for the 40–60 years of age range. Microbioelement contents show a similar tendency, while microbioelements and toxic elements reach maximum contents in donors aged 60–80 years. All elements show content decreases in livers from the oldest group (>80 years). Silica contents increase with age. Variability of element contents is lowest in the older subpopulations. Livers with lesions show lower element contents and variability. The results are compared to literature data for regions of Poland assumed to be of low pollution and to data from comparable regions in Japan and Hungary. Up to our knowledge, this paper is the first work describing the total contents, as distinct from contents of selected elements, of mineral substance in human livers.  相似文献   
172.
Environmental Geochemistry and Health - The effects of bath therapy are complex and result from a unique interaction between the aquatic environment and the human body functions. The effect of bath...  相似文献   
173.
This study was conducted to improve the ability of indigenous New Zealand white-rot fungi to remove pentachlorophenol (PCP) from contaminated field soil. The effects of different bioaugmentation conditions on PCP removal and extracellular enzyme expression were measured in the laboratory. The conditions were fungal growth substrate and co-substrate composition, culture age, and Tween 80 addition to the contaminated soil. The fungi used were Trametes versicolor isolate HR131 and Trametes sp. isolate HR577. Maximum PCP removal was 70% after 7 wk from a 1043 mg kg(-1) PCP-contaminated soil inoculated with an 11-d-old fungal culture of T. versicolor isolate HR131. There was minimal production of undesirable pentachloroanisole by the fungi. Tween 80 addition had no affect on PCP removal. Poplar sawdust was more suitable as a fungal growth substrate and a co-substrate amendment for PCP removal and extracellular enzyme expression than the locally available pine and fir sawdust. Pentachlorophenol removal was not necessarily correlated with extracellular enzyme expression. The research results demonstrate that PCP biodegradation was affected by inoculum culture age, by the presence of a co-substrate amendment, and by growth substrate composition after white-rot fungal bioaugmentation into PCP-contaminated field soils.  相似文献   
174.
The influence of the polymers' properties on the solid-phase extraction recovery was studied. Different porous copolymers were used: di(methacryloyloxymethyl)naphtalene-divinylbenzene with ester functional groups (DMN-DVB), 4,4'-bis(maleimido)diphenylmethane-divinylbenzene with imide functional groups (BM-DVB), p,p'-dihydroxydiphenylmethane diglycidyl methacrylic ester-divinylbenzene (MEMDE-DVB) and p,p'-dihydroxydiphenylpropane diglycidyl methacrylic ester-divinylbenzene (MEDDE-DVB) with ester end hydroxyl functional groups. The extraction properties of new synthesized polymeric sorbents were compared with these of two commercial polymeric sorbents: styrene-divinylbenzene (SDB-1) and styrene-divinylbenzene with modified surface (StrataX). These sorbents were used in the SPE of phenol and hydroquinone from water samples.  相似文献   
175.
The aim of the present study was to compare the degrading capabilities of eight ligninolytic fungal representatives towards a technical mixture of polychlorinated biphenyls (Delor 103). Axenic cultures of the fungi, either in complex or N-limited liquid media, were spiked with the technical mixture of Delor 103. All of the fungal strains were able to degrade the pollutant significantly after 6weeks of incubation in both media. Outstanding results were achieved by the treatment with Pleurotus ostreatus, which removed 98.4% and 99.6% of the PCB mixture in complex and mineral media, respectively. This fungus was the only one capable of breaking down penta- and hexachlorinated biphenyls in the complex medium. Ecotoxicological assays performed with the luminescent bacterium Vibrio fischeri demonstrated that all of the fungal strains employed in this study were able to remove the toxicity only temporarily (e.g., after 28d of incubation), while P. ostreatus was capable of suppressing the toxicity associated to PCBs along the whole incubation period in both media. We also performed an extensive set of qualitative GC/MS analyses and chlorinated derivatives of hydroxy- and methoxy-biphenyls were detected along with monoaromatic structures, i.e. chlorobenzoic acids, chlorobenzaldehydes and chlorobenzyl alcohols. This results indicate that both intracellular (cytochrome P-450 monooxigenase, aryl-alcohol dehydrogenase and aryl-aldehyde dehydrogenase) and extracellular (ligninolytic enzymes) enzymatic systems could be involved in the biotransformation of PCB by ligninolytic fungi. The data from this work also document that the fungi are able to degrade further the main metabolites on the PCB pathway (i.e. chlorobenzoic acids) simultaneously with PCBs.  相似文献   
176.
The purpose of this study was to determine certain blood biochemical parameters in hens of Isa Brown breed (n = 20) after nickel administration. Animals were divided into four groups (K, P1, P2, P3). Experimental hens (n = 5; in each group) received nickel (NiCl2) as peroral administration in drinking water in various doses (P1 - 0.02 g NiCl2/L; P2 - 0.2 g NiCl2/L; P3 - 2.0 g NiCl2/L of drinking water) for 28 days. The last group - K (n = 5) was the control, receiving no nickel. Biochemical parameters of mineral profile (calcium; phosphorus; magnesium; sodium; potassium) and of energy and enzymatic profile [(glucose; total cholesterol; total proteins; triglycerides; alanine aminotransferase (ALT) aspartate aminotransferase (AST) gamma glutamyl transferase (GGT) and glutamatdehydrogenase (GLDH)] were analyzed in blood serum on Day 0, 7, 14, 21 and 28 of the experiment. Average levels of mineral metabolism parameters were relatively stable apart from calcium. The evaluation registered a significant decrease in calcium during the experiment mainly in the group with highest nickel concentration in drinking water. No significant differences were detected between groups in energy and enzymatic profile apart from the concentrations of ALT on Day 7. In conclusion, there were significant associations between nickel levels and calcium and ALT in blood serum of the hens. No significant differences were detected in other biochemical parameters of mineral profile (P, Mg, Na, K) and energy and enzymatic profile (glucose, total cholesterol, total proteins, triglycerides, AST, GGT and GLDH) after nickel administration. Our results may contribute to an evaluation of reference levels of analyzed parameters, to monitor the health and nutritional status of hens. In this study also the negative effect of nickel mainly on calcium metabolism was detected.  相似文献   
177.
In the context of a monitoring program, persistent organic pollutants (POPs) were quantified in the blood of 10 year old children at four different demographic regions in Baden-Wuerttemberg, a highly industrialised federal state in South West Germany. DDE, HCB, PCB 138, PCB 153 and PCB 180 were measured in 1996/1997, 1998/1999, 2000/2001 and 2002/2003 in individual samples of about 400 children per year. PCDD/PCDFs and some relevant coplanar PCBs were determined in pooled samples from children in seven cycles from 1993 to 2003. Blood concentrations of the investigated compounds decreased in that time period by a factor of 2-4 with the exception of most PCDFs. The concentrations of POPs in the blood of the children were distinctly lower than the concentrations reported for adults. Breast feeding was associated with about 30% higher median concentrations of DDE, HCB, PCBs and a 30% increase for mean PCDD/PCDF concentrations. Concerning demographic differences, significant lower concentrations of HCB, PCBs and PCDD/PCDFs could be seen in children from Mannheim compared to the region of Aulendorf. About 10-20% higher concentrations were found in boys compared to girls for HCB, indicator PCBs and PCDD/PCDFs. The pattern of non-ortho and mono-ortho PCBs in the blood of children was similar to the pattern reported for mother's milk, and PCB 126 and PCB 156 contributed about 70% to the toxicity of dioxin-like PCBs and about one-third to total TEQ including PCDD/PCDFs.  相似文献   
178.
Herbicides pose a significant threat to the natural environment, in particular in soils that are most exposed to plant protection agents. Prolonged herbicide use leads to changes in soil metabolism and decreases soil productive potential. In this study, the influence of carfentrazone-ethyl (CE) on the microbiological and biochemical properties of soil and the yield of Triticum aestivum L. was evaluated. Carfentrazone-ethyl was applied to sandy loam (pHKCl – 7.0) in doses of 0.000, 0.264, 5.280, 10.56, 21.18, 42.24, 84.48 and 168.96 µg kg?1 DM soil. Soil samples were subjected to microbiological and biochemical analyses on experimental days 30 and 60. Carfentrazone-ethyl disrupted the biological equilibrium in soil by decreasing the abundance and biodiversity of soil-dwelling microorganisms, the activity of soil enzymes, the values of the biochemical activity indicator and spring wheat yields. Carfentrazone-ethyl had the most adverse effects when applied in doses many fold higher than those recommended by the manufacturer. The toxic effects of CE were also determined by its soil retention time. Soil treated with CE was characterized by higher counts of oligotrophic bacteria, organotrophic bacteria, bacteria of the genus Azotobacter, actinomycetes and fungi on day 60, and spore-forming oligotrophic bacteria on day 30. The activity of dehydrogenases, urease, alkaline phosphatase and β-glucosidase was higher on day 30 than on day 60.  相似文献   
179.
Adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-metylphenoxyacetic acid (MCPA) from aqueous solution onto activated carbons derived from various lignocellulosic materials including willow, miscanthus, flax, and hemp shives was investigated. The adsorption kinetic data were analyzed using two kinetic models: the pseudo-first order and pseudo-second order equations. The adsorption kinetics of both herbicides was better represented by the pseudo-second order model. The adsorption isotherms of 2,4-D and MCPA on the activated carbons were analyzed using the Freundlich and Langmuir isotherm models. The equilibrium data followed the Langmuir isotherm. The effect of pH on the adsorption was also studied. The results showed that the activated carbons prepared from the lignocellulosic materials are efficient adsorbents for the removal of 2,4-D and MCPA from aqueous solutions.  相似文献   
180.
Environmental Science and Pollution Research - Curcumin is a polyphenolic compound that exhibited good anticancer potential against different types of cancers through its multi-targeted effect like...  相似文献   
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