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Deltamethrin (DEL) is a synthetic pyrethroid widely used as an insecticide. The aim of our study was to determine the effect of a single exposure of female albino Swiss mice to DEL (at doses of 8.3 mg/kg, 20.75 mg/kg, or 41.5 mg/kg) on parameters of liver and kidney function and activities of antioxidant enzymes in these organs. The activity of alanine transaminase (ALT) in the blood sera of the experimental animals was not significantly elevated after exposure to DEL. Asparagine transaminase (AST) activity was signifi cantly higher in the groups exposed to the moderate and the highest dose of DEL. The levels of creatinine in the blood sera of the experimental animals did not significantly differ among the groups. The activities of superoxide dismuthase (SOD) and glutathione peroxidase (GPx) were significantly reduced in the livers of mice exposed to the highest dose of DEL in comparison with controls. In the kidneys, however, the SOD and GPx activities were significantly elevated after exposure to the highest dose of DEL. In conclusion, DEL produces oxidative stress in the livers and, to a lesser degree, the kidneys of exposed animals.
Fenpropathrin (FEN) was administered intraperitoneally in doses of 2.38 mg/kg, 5.9 5mg/kg, or 11.9 mg/kg b.w. to mice for 28 consecutive days. FEN did not significantly affect the activity of alanine transaminase (ALT) in the sera. Superoxide dismutase and glutathione peroxidase activities were significantly elevated in the liver after a 28-d exposure to moderate or highest doses of the pesticide. These results demonstrate that the 28-day exposure to FEN leads to an up-regulation of expression of antioxidant enzymes in response to an oxidative stress in mouse liver without causing a significant increase in ALT activity.
The aim of the study was to find out if subtoxic doses of fenitrothion (0.1 LD₅₀, LD₅₀ =166.6 mg/kg) administered to mice exposed to transient oligaemic brain hypoxia induced by bilateral clamping of the carotid arteries (BCCA) influence memory processes, movement activity, and coordination. The BCCA was carried out under ketamine + xylazine anaesthesia. Common carotid arteries were clamped for 30 min. Twenty-four hours later; the animals were injected intraperitoneally with 0.1 LD₅₀ of fenitrothion. Controls and sham-operated animals (with carotids separated but not clamped) were injected with respective volumes of bidistilled water. All the animals were trained in passive avoidance (PA) task. The examination of memory retention in PA was done 24 h later followed by testing of fresh spatial memory in a Y- maze, movement co-ordination, and spontaneous movement activity in a 30-min period. Fenitrothion did not significantly alter memory processes in the examined mice. However, the movement coordination was significantly impaired in animals that underwent BCCA alone as well as being oligaemic and under the influence of fenitrothion vs control groups. The same groups demonstrated significantly impaired spontaneous movement activity vs controls.
The purpose of the present study was to examine whether the effects of exposure to 0.1LD₅₀ of bifenthrin on memory processes, movement activity, and coordination could be exacerbated by transient reduction of cerebral oxygen supply. The transient occlusion of both common carotid arteries (BCCA) in adult mice was performed under anaesthesia. Intraperitoneal LD₅₀ for bifethrin was estimated to be 16.1mg/kg b.w. The memory retention was evaluated in a step-through passive avoidance task (PA), working spatial memory in a Y-maze, movement coordination on a rota-rod, and movement activity in an automated device. Long-term memory impairment caused by bifenthrin was exacerbated by BCCA. Movement co-ordination was significantly altered in animals treated with the compound. Movement activity was slightly decreased in animals after BCCA and pesticide injection. These results indicate that cerebral oligaemic hypoxia potentiates long-term memory impairing effect of bifenthrin.
Trace elements are important in appropriate organisms functioning. Among them manganese as well as silicon play essential roles. Manganese takes parts in composition of many enzymes, it is a cofactor of numerous enzymatic reactions, a structural element of skin and bones, it also prevents osteoporosis. Its very important role in reproduction processes and in central nervous system has been already stated. Silicon is a very important factor, which takes active part in vital processes, regenerating tissues and increasing general immunity of organism. It has basic meaning in metabolism of connective tissue, collagen formation and bone development and mineralization, cartilages, hair, nails, teeth in human and animals, and also in processes of convalescence and ageing of organism. The aim of our experiment was to estimate influence of manganese chloride on the concentration of silicone in mice tissues. It has been find out that doses of administered manganese as well as the duration of exposure have influence on silicon content in tissues.
Badano wpływ doustnego 8 tyg. narażenia szczurów na rtęć (150 mg/dm3 w przeliczeniu na czysty metal) wprowadzana do ustroju w postaci roztworu HgCl2 na tkankowe stężenia magnezu, wapnia i krzemu. W większości tkanek stwierdzono statystycznie istotne zmiany w przypadku ste˛z˙enia magnezu i wapnia, natomiast nie zaobserwowano zmian w ste˛z˙eniu krzemu.
Przeprowadzono badania wpływu magnezu na aktywność enzymów przeciwutleniających: dysmutazy ponadtlenkowej [EC 1.15.1.1], peroksydazy glutationowej [EC 1.11.1.9] i katalazy [EC 1.11.1.6] w mózgu, wątrobie i nerkach szczurów poddanych intoksykacji ochratoksyną А (ОТА). Podawanie przez 14 dni ochratoksyny A powodowało obniżenie aktywności badanych enzymów we wszystkich badanych tkankach w stosunku do grupy kontrolnej. Suplementacja magnezowa częściowo niwelowała negatywny wpływ trucizny.
Manganese is very important trace element whose mechanism of actions involves activity regulation of enzymes taking part in key metabolic processes in organisms. It is a structural element of skin and bones, it also prevents osteoporosis. Its very important role in reproduction processes and in central nervous system has been already stated. The magnesium ion is of great importance in physiology by its intervention in 300 enzymatic systems, its membrane role and its function in neuromuscular excitability. The first pool of magnesium in organism is skeleton. The principal site of magnesium excretion are kidneys, which show important magnesium regulation mechanisms. For intestinal absorption, renal metabolism, bone accretion and resorption, magnesium shows analogies with calcium. Calcium is important macroelement in enzyme activation and inhibition, muscle and nerve function, and intracellular metabolism of all organisms. It is the main component of bones, where it is stored in organism. The aim of our work was to estimate influence of manganese chloride administration on concentrations of magnesium and calcium in mice tissues. Significant changes in magnesium and calcium content in dependence on the doses of administered manganese as well as the duration of the exposure have been stated in our experiment.
The aim of this research was to determine to what degree women in the climacterium period know the benefits and dangers resulting from hormone replacement therapy (HRT). The most common benefits, resulting from HRT, are doing away with the fits of heat (34.2%), prevention of osteoporosis (33.3%), emotional stability (29.2%) and prolongation of the lifespan and general fitness (15.5%). Most of the women that used HRT are well-informed about the mechanism of the medicimes efficacy, they are also aware of short-term benefits resulting from the therapy. The most common fear that women using substitution hormonotherapy have is the fear of neoplasmatic disease.
The aim of the study was to examine the toxic effect of different doses of zearalenone on liver cells by estimating mycotoxin influence on antioxidant systems and on formation of free radicals in the liver. The research was carried out on male Wistar rats. The rats were divided into nine groups of 10 animals each. Group A was orally given 8% ethyl alcohol once a day for 10 d. Groups B, C, D, and E were given, orally once a day 50, 100, 200, and 500 µg/kg b.w. of zearalenone in alcohol solution for 10 days. The animals from groups X, Y. and Z received a single dose of 1, 2, and 3 mg/kg b.w of zearalenone, respectively, and group W (control) - a single dose of 8% ethyl alcohol. The liver was removed and homogenised. Glutathione peroxidase and superoxide dismutase activities, and concentration of L-ascorbic acid in the homogenate were determined. Received outcome and statistical analysis showed the essential fall of superoxide dismutase activity after 10 d of administering 200 and 500 µg/kg b.w of ZEA in comparison with the control group, and drop of glutathione peroxidase activity after 500 µg/kg b.w. dose. The results of the experiment showed that oxidative stress is one of the main toxic effects of zearalenone activity. Low doses of zearalenone applied for a long time do not have an influence on free radical reaction. Short-lasting zearalenone influence does not cause changes in the activity of antioxidant enzymes.
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