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The aim of the study was to determine plasma levels of vitamin C and reduced glutathione (GSH) in sows between the day 14 prepartum and day 14 postpartum. The study involved twenty-four sows of three breeds - Polish Large White (PLW), Polish Landrace (PL) and PLWxPL aged 1-3 years. All the animals were from one closed-cycle production farm. The mean vitamin C level on days 13-14 prepartum reached 0.49 ±0.19 mmol/g of protein and decreased significantly (P<05) at 24-48 h postpartum to 0.33 ±0.19 mmol/g of protein. On days 6-7 and 13-14 postpartum, the vitamin C level further decreased to 0.17 ±0.006 and 0.15 ±0.007 mmol/g of protein, respectively. The mean GSH level on days 13-14 before delivery was 0.071 ±0.009 mmol/g of protein and decreased significantly (P0.05) at 24-48 h before delivery to 0.062 ±0.018 mmol/g of protein. In this period, the mean GSH level was similar to that observed during the first 24-48 h postpartum. On day 6-7 after delivery, the level of GSH reached the values observed on days 13-14 and 6-7 prepartum. On days 13-14 postpartum, the level of GSH was found to be 0.115 ±0.029 mmol/g of protein and was significantly higher (P<0.001) compared to that on days 13-14 prepartum. The findings suggest that porcine levels of vitamin C and glutathione decrease during the periparturient period, which may lead to a decreased antioxidant defence system and an imbalance in redox homeostasis.
The aim of this study was to investigate changes in selected parameters of cellular immune response in the conditions of endotoxin fever and pyrogenic tolerance in pigeons. On the first day of observation the experimental birds (n=18) were intravenously injected with Escherichia coli LPS at a dose of 10 μg/kg b.w., while the control animals (n=6) received apyrogenic physiological saline also in the form of injection. On the second and the third day of the experiment LPS was injected additionally at 24 h intervals. Four and a half hours after the saline and pyrogen administration blood samples were collected from the control and experimental pigeons. The following immunological assays were performed: WBC, leucogram and immunophenotyping of lymphocyte subsets in peripheral blood, i.e. CD 3+ (T lymphocytes), CD 4+ (T helper lymphocytes) and CD 8+ (T suppressor/ cytotoxic lymphocytes) cells. In the conditions of endotoxin fever (i.e. after the first LPS injection) leucopenia, monocytopenia, heterophilia and eosinophilia were observed. Additionally, the immunophenotyping of peripheral blood lymphocytes indicated an increase in percentage of CD 3+, CD 4+ and CD 8+ cells in response to the single injection of LPS. In contrast, the consecutive injections of LPS, which created a pyrogenic tolerance effect, caused a decrease in WBC value, heteropenia, eosinopenia and lymphocytosis. Moreover, during this state an increase in percentage of CD 3+ and CD 8+ cells was demonstrated in contrast to the percentage of CD 4+ lymphocytes. The general tendencies in cellular immune response of the affected pigeons in the conditions of endotoxin fever and pyrogenic tolerance aim at activation of defence mechanisms against LPS for its prompt elimination from the animal’s organism.
The review focuses on the role of two groups of proteins (anti-nutritive and toxic) in plant defence against insect herbivores.
The review focuses on the progress in recent decades on various aspects of molecular responses taking place in plants infested by herbivorous arthropods. The diversity of herbivoryinitiated molecular events was presented with special emphasis on: (1) elicitors and a general recognition process, (2) signal perception, transduction, integration and defence gene expression, (3) cross-talk between salicylate- and jasmonate-dependent defence pathways, and (4) regulators of plant defence responses.
Lupine diseases caused by pathogenic fungi constitute a serious problem in agriculture. They lead to partial yield loss and deterioration of crop quality through the changes in biochemical composition of seeds or their contamination with mycotoxins. Some of common lupine diseases are fusarioses caused by Fusarium oxyspomm f. sp. lupini. Morphometric and metabolic changes were investigated in yellow lupine seedlings infected with F. oxyspomm f. sp. lupini. It was found that infection caused temporary inhibition of seedling growth, overcome at later development, and activation of ß-glycosidase and peroxidases. The changes in enzymes activity indicate the induction of defense mechanism against F. oxyspomm f. sp. lupini and inhibition of pathogen spread.
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