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421.
Plant Foods for Human Nutrition - Bioclimatic air ionisation system (BI) works by neutralising air pollutants and microorganisms by means of oxidation with “activated oxygen”. We...  相似文献   
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The polymorphic loci of the bovine prion protein (PRNP) gene, comprising 23-bp insertion/deletion (23-bp indel) within the promoter sequence and 12-bp insertion/deletion (12-bp indel) within the intron 1 sequence, are located in regions which play a key role in gene expression. The objective of this study was to determine whether the 23-bp and 12-bp insertion/deletion polymorphism within the PRNP gene leads to significant differences in the blood lymphocyte profile and to investigate changes in the composition of these cells in cattle naturally infected with Bovine Leukemia Virus. An analysis of the effect of the bovine PRNP gene polymorphism on the blood lymphocyte profile revealed considerable differences between animals with the 23-bp indel genotypes, and small and statistically non-significant differences between those with the 12-bp indel genotypes. 23-bp del/del homozygotes had a significantly lower percentage of T lymphocytes with the phenotypes CD2 (P < 0.01), CD8 (P < 0.01) and WC1-N2 (P < 0.05), and a higher ratio of CD4 to CD8 T lymphocytes, compared to animals with the 23-bp ins/ins genotype. The obtained results indicate that the 23-bp indel polymorphism, in contrast to the 12-bp indel polymorphism, has a significant effect on changes in the blood lymphocyte profile. The size of blood lymphocyte subpopulations was also found to change under the influence of enzootic bovine leukosis. The direction of those changes in EBL-positive animals is consistent with that observed in 23-bp del/del homozygotes, which may testify to the adverse effect of this genotype on immunological efficiency.  相似文献   
424.
The present study provides insight into the diversity of 147 Xanthomonas campestris pv. campestris (Xcc) isolates obtained from six Brassica oleracea vegetable crops (broccoli, cabbage, cauliflower, collard greens, kale, kohlrabi) and the winter oilseed rape crop Brassica napus, collected from different regions in Serbia in 2014. The XCF/XCR pathovar-specific primer set was used for fast preliminary identification. In repetitive sequence-based PCR (BOX, ERIC and REP) of all isolates, a higher level of genetic diversity was found in winter oilseed rape isolates compared to isolates from the other hosts. ERIC and REP-PCR showed the highest heterogeneity, with 10 and nine banding patterns, respectively. The REP-PCR results showed the highest correlation (70%) with those obtained with multilocus sequence analysis (MLSA), performed with 10 housekeeping genes (fusA, gap-1, gltA, gyrB1, lacF, lepA, rpoD, dnaK, fyuA and gyrB2). Three distinct phylogenetic groups of winter oilseed rape isolates were detected using MLSA. Two genes, gltA and rpoD, showed the greatest ability to identify and discriminate winter oilseed rape Xcc isolates from isolates of the other six hosts. The lepA gene exhibited specific three-nucleotide changes in sequences of some of the isolates. Results of virulence testing of 18 representative isolates showed statistically significant host–pathogen specialization for Xcc isolates from winter oilseed rape, cauliflower, kale and kohlrabi. In conclusion, oilseed rape isolates are more genetically diverse and show greater specialization to their host in comparison to the rest of the tested isolates from other brassica hosts.  相似文献   
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Increasing the amount of n‐3 PUFA in carp meat is one of the most important tasks in enhancing its overall quality. However, the relative influence of supplemental feed and natural feed on the FA profile of cultivated carp flesh is not well documented, making it difficult to choose the most efficient strategy. Carp diet composition and diet and flesh fatty acid profiles were simultaneously followed in order to determine the influence of pelleted feed compared to natural feed on fatty acid profiles of carp tissues. Pelleted feed clearly dominated over zooplankton and Chironomidae in the carp diet, producing carp tissue fatty acid profiles closely resembling those of pelleted feed. However, increase in the abundance of zooplankton over the course of the investigation resulting in concomitant increase of its proportion in feed bulk was in strong positive correlation with increase in n‐3 HUFA in the dorsal muscle. n‐3 PUFA enrichment of supplemental feed could be the dominant mechanism in production of carp meat rich in n‐3 PUFA. However, even a small increase in natural feed availability could significantly change the diet of common carp and result in considerable improvement of meat quality with regard to n‐3 HUFA content.  相似文献   
427.
In this study, we investigated the physical, chemical and biological parameters of the water column at two stations under different trophic conditions during a 1‐year period (from September 2005 to September 2006) in an aquaculture area. The investigation was performed monthly at a station inside the fish farm in Maslinova Bay (middle Adriatic Sea, Croatia) and at a control station located in the Hvar Channel in the vicinity of the farm. The results showed that the concentrations of dissolved nutrients were slightly enhanced at the farm station in comparison with the control station, although those differences were not statistically significant, nor were the differences in oxygen saturation recorded during the investigation period. As opposed to the chemical parameters, considerably higher deviations were recorded for biological parameters as demonstrated by a significant increase in phytoplankton biomass and primary production (measured in situ) at the farm station, particularly during the summer season. Phytoplankton community structure analysis showed that the phytoplankton composition at the farm was mostly determined by seasonal changes rather than by the influence of fish farming. In Maslinova Bay, no causal links were identified between increased biomass and the appearance of toxic species.  相似文献   
428.
The aim of the present study was to investigate the effect of thermal treatment methods, such as microwave cooking, steaming, and shallow pan-frying on fatty acids composition in northern pike fillets. All methods of thermal treatment increased fat content in the fillets. Microwave cooking decreased the proportion of saturated fatty acids and increased the proportion of total, n-3, and n-6 polyunsaturated fatty acids as compared with fresh fillets. Steam cooking did not affect the proportion of saturated, monounsaturated, and polyunsaturated fatty acids, whereas pan-frying significantly increased the proportion of monounsaturated and n-6 polyunsaturated fatty acids. All cooked fillets, regardless of the thermal treatment used, had acceptable n–6/n–3 ratio; however, microwave cooking enabled fish products to obtain more beneficial n-6/n-3 ratio than frying. Due to high polyunsaturated fatty acids content and low n-6/n-3 ratio, microwave cooking may be recommended for preparing wild pike fillets in households.  相似文献   
429.
The effects of farming on planktonic microbial communities were investigated at the coastal sea bass/sea bream farm in the oligotrophic middle Adriatic Sea. Analyses of nutrients, chlorophyll a, cyanobacteria (Prochlorococcus), heterotrophic bacteria and nanoflagellates (both pigmented and heterotrophic) were carried out on samples taken during six seasonal cruises at different water depths. Farming activity increased the natural concentrations of some nutrients (ammonium, nitrite, phosphate, dissolved inorganic nitrogen) and changed their seasonal pattern. The values still remained typical for oligotrophic environ‐ments demonstrating no risk for eutrophication. Enhanced nutrient supply provoked an immediate increase in abundances of both autotrophic and heterotrophic microbial groups (except pigmented nanoflagellates) and chlorophyll a. The effect of farming was more visible for the heterotrophic microbial component. Results from this study reveal a potential common pattern of microbial response to farming in the oligotrophic environments. It also suggests the importance of heterotrophic microbial web in transferring the matter and energy released from the fish farms in nutrient poor environments.  相似文献   
430.
The purpose of this work was to acquire more information on the capacity of in vitro grown Centaurium erythraea Gillib. normal and hairy root cultures to simultaneously regenerate adventitious buds and to evaluate the variations induced on regeneration response by treatments with six cytokinins. Explants from normal and hairy root cultures were cultured on half-strength MS medium (1/2 MS) with kinetin (KIN), N6-benzylaminopurine (BA), 6-γ,γ-dimethylallylaminopurine (2IP), N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU), 1-Phenyl-3-(1,2,3-thiadiazol-5-yl)urea (TDZ) and 6-[4-Hydroxy-3-methyl-but-2-enylamino]purine (ZEA), used alone in six different concentrations. The average number of adventitious buds per explant was promoted by all of cytokinin treatments. Urea-type cytokinins, TDZ and CPPU were more effective for the induction the morphogenesis of adventitious buds than adenine-type cytokinins. We found that the 1.0 μM CPPU induced the largest number (25.6, 18.2, respectively) of adventitious buds in normal and hairy root culture. TDZ-supplemented media induced highest number of adventitious buds (24.2) from normal root explant, but from hairy root explant average number of buds is lower (20.5). Regenerated shoots were excised and placed on 1/2 MS medium without hormone. The rooted plantlets were successfully acclimatized in greenhouse conditions.  相似文献   
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