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排序方式: 共有23条查询结果,搜索用时 156 毫秒
1.
A specific objective of this paper was to evaluate seasonal changes in bioactive compounds level (carotenoids and polyphenols) in juice prepared from organic and non-organic tomatoes in Poland. In the examined tomato juice, the content of dry matter, vitamin C, carotenoids as well as polyphenols (by HPLC method) has been measured. The presented results indicate the impact of the growing system and the year of production on the composition of tomato juice. The organic tomato juice contained significantly more beta-carotene, chlorogenic acid, rutin as well as more total phenolic acids, gallic acid, p-coumaric acid, total flavonoids, quercetin-3-O-glucoside and quercetin in comparison with the non-organic. The tomato juice from 2008 contained significantly more carotenoids and some flavonoids compared to the one produced in 2009, which contained significantly more dry matter, vitamin C, as well as quercetin and it derivatives.  相似文献   
2.
The effect of a standard, single dose therapy with tulathromycin was investigated on the postvaccinal humoral and cellular immune response in pigs vaccinated against swine influenza. Forty‐five pigs, divided into 3 groups, were used (control not vaccinated (C, n = 15), control vaccinated (CV, n = 15), and experimentally received tulathromycin (TUL, n = 15)). For vaccination of pigs, an inactivated, commercial vaccine was used. Pigs from TUL group received single dose of tulathromycin intramuscularly, at the recommended dose (2.5 mg/kg body weight). Pigs from TUL and CV groups were vaccinated at 8 and 10 weeks of age. The specific humoral and cellular immune response against swine influenza virus (SIV) was evaluated. The results of present study showed that humoral postvaccinal response after vaccination against SIV can be modulated by treatment with tulathromycin. In pigs from TUL group, the significantly higher titers of anti‐SIV‐specific antibodies were observed 4 and 6 weeks after booster dose of vaccine. Simultaneously, T‐cell‐mediated immune response against SIV was not affected by tulathromycin. Our recent study confirmed the importance of defining the modulatory activity of tulathromycin because of its influence on the immune response to vaccines. Since the antibodies against hemagglutinin are crucial for the protection against SIV, the present observations should prompt further studies on the practical significance of recent results in terms of clinical implications (postvaccinal protection) in the field conditions.  相似文献   
3.
The aim of the study was to evaluate the effects of a diet containing different levels of Cu in two different chemical forms (carbonate and nanoparticles) on redox reactions and epigenetic changes in a rat model. For 4 weeks, five experimental groups (eight rats in each) were fed diets with two dosages of added Cu (standard—6.5 mg/kg or half of the standard dosage—3.25 mg/kg, and as a negative control no additional Cu in the mineral mixture) in two forms (standard—CuCO3 and copper nanoparticles). Addition of Cu nanoparticles resulted in higher Cp (ceruloplasmin) activity and LOOH (lipid peroxides) and MDA (malondialdehyde) content, as well as decrease the CAT (catalase) activity and level of PC (protein carbonyl), 3‐NT (3‐nitrotyrosine), 8‐OHdG (8‐hydroxydeoxyguanosine), GSH + GSSG (total glutathione) and DNA methylation. Reducing the dose of copper resulted in a decrease in the level of LOOH and GSH + GSSG as well as CAT activity, but increased the level of PC and methylated DNA. Based on these evidence, we concluded that addition of copper nanoparticles in the diet reduces protein oxidation and nitration as well as DNA oxidation and methylation. Lowering the level of Cu in the diet increases the oxidation of proteins and DNA methylation.  相似文献   
4.
The effects of Cd and Cu on embryos and larvae of the ide Leuciscus idus were evaluated. The ide is an European cyprinid fish, natural populations of which tend to decrease. The ide is also used as a bioindicator organism to evaluate water quality. However, sensitivity of ide early developmental stages to heavy metal intoxication is not known. Fish were exposed to Cd or Cu (100 μg/L) during embryonic, larval or both developmental periods. Survival of the embryos, time of hatching, size and quality of newly hatched larvae were evaluated at the end of embryonic period. Correctly developed larvae from the control and Cd or Cu-exposed groups were transferred to clean water, Cd or Cu solutions (100 μg/L) immediately after hatching. Larval development was observed, and the larvae were photographed. Time of yolk sac resorption, onset of active feeding and swim bladder inflation were evaluated, and the measurements were done on body and swim bladder size. The results showed that exposure of embryos to Cd and Cu significantly reduced embryonic survival and increased frequency of body malformations and death in newly hatched larvae and delayed hatching. Exposure to Cd and Cu during larval period reduced larval survival, growth and delayed development (yolk utilization, beginning of active feeding and swim bladder inflation). Cadmium was more toxic to the ide embryos and larvae than copper. Exposures to metals during embryonic period alone caused adverse impact on larval performance even when larval development took place in clean water. However, exposure of embryos to Cu reduced toxic impact of metal on larvae in continuous Cu exposure compared to the non-preexposed fish, but no such an effect occurred in case of Cd exposure. The results show that even a short-term exposure to Cd or Cu during early development of ide may adversely affect recruitment of this species. Among the measured endpoints, quality of newly hatched larvae (frequency of body malformations and larvae dead immediately after hatching) and swim bladder size were the most sensitive to intoxication with both metals. Embryos were more sensitive to Cu intoxication than larvae, while in case of Cd, sensitivity of both stages was similar.  相似文献   
5.
Nanotechnology is a dynamically developing field of scientific and industrial interest across the entire world, and the commercialization of nanoparticles (NPs) is rapidly expanding. Incorporation of nanotechnologies into a range of manufactured goods results in increasing concern regarding the subsequent release of engineered NPs into the environment. One of the biggest threats of using NPs is the transfer and magnification of these particles in the trophic chain. The aim of the studies was the evaluation of the distribution of TiO2 NP contamination in the aquatic ecosystem under laboratory conditions. Bioaccumulation of TiO2 NPs by plants (Elodea canadensis) and fish (Danio rerio) in the source of contamination was investigated. The studies were focused on the consequences of short-term water contamination with TiO2 NPs and the secondary contamination of the components of the investigated model ecosystem (plants, sediments). It was found that in the fish and the plants exposed to NP contamination, the amount of Ti was higher than in the control, indicating an effective bioaccumulation of NPs or ions originating from NPs. It was clearly shown that the NPs present in the sediments are available to plants and fish. Additionally, the aquatic plants, an important trophic level in the food chain, can accumulate NPs and be a source of NPs for higher organisms. It was concluded that even an incidental contamination of water by NPs may result in long-term consequences induced by the release of NPs.  相似文献   
6.
7.
The oak (Quercus robur L.) regeneration intensity was assessed in the core area of the Białowieża National Park (BNP) in Poland with respect to the selected ecological factors. The emphasis was placed on the response of oak regeneration to disturbances, including the large-scale dieback of spruce stands. Defining their effect could help predicting the role of oak in naturally developing lowland forest ecosystems in the European hemiboreal zone. The results of the study challenge the opinion that the ‘lime-oak-hornbeam forest’ is a ‘climax’ community, confirming a very poor regeneration represented by only two saplings taller than 0.5 m per hectare. By contrast, in spruce-dominated communities, from 49 to 848 taller saplings per hectare were found. The occurrence of saplings was associated with discontinuous canopy of late seral stage of stands, as well as with large gaps. Most of the best quality grown-up oak saplings developed in the immediate neighbourhood of spruce logs. The results of the research indicate that ‘lime-oak-hornbeam forest’ (Tilio-Carpinetum) should be rather perceived as a transient community, evolved from relict, culturally modified, oak woodlands. Because spruce had become a dominating species only after abandoning in mid-1800s the historical regime of anthropogenic disturbances (involving frequent forest fires), the observed phenomena related to the disintegration of spruce stands had probably no precedent over the last 500 years. To confirm whether the massive decline of spruce stands will finally result in the successful establishment of the new canopy oak generation, both in Białowieża and other forests of hemiboreal zone, further research is needed.  相似文献   
8.
Two liquid culture systems, rotary shaker (RS) and temporary immersion system (TIS) for the propagation of Rosa rubiginosa and Rosa tomentosa were investigated and compared with solid medium culture. Shoot tips were grown on basic Murashige and Skoog medium with 20 mg dm?3 Fe EDDHA, 1 µM BA, 1.5 µM GA3 and 3% sucrose for six weeks. Of the different culture systems, liquid cultures resulted in better growth and development of roses. Both RS and TIS cultures improved biomass growth, multiplication rate, leaf blade area and plant height; however, RS reduced the shoot dry mass content. There were no changes in the content of chlorophyll a, b, a + b in plants developed in the tested systems. Use of a solid medium favoured the accumulation of phenolic compounds, soluble sugars, and carotenoids, but it was accompanied by browning and necrosis of shoots. Plants propagated in TIS were characterised by the high content of phenolic compounds and soluble sugars, but they had the highest multiplication rate. Use of TIS resulted in eight times the number of shoots for R. tomentosa and twice as many for R. rubiginosa compared to solid medium.  相似文献   
9.
The effect of vaccinating pregnant cows with an inactivated vaccine against Mannheimia haemolytica, BRSV and PI3V infections on selected immune responses in their offspring was examined. Blood samples were collected weekly for 12 weeks from six newborn calves from each of vaccinated (experimental) and unvaccinated (control) dams. Specific antibodies to M. haemolytica, BRSV and PI3V and mean values of IgA, IgG concentrations were significantly higher in the experimental calves compared with the controls. However, specific antibody titres to adenovirus type 3, BHV1 and BVDV in the experimental calves had constant levels while the control group levels changed. The IgM, Hp and SAA concentrations generally increased until week 8 in the experimental group, but the control group titres became higher after week 9. This study demonstrates that specific immunisation of cows pre-partum significantly stimulated parameters associated with immunity and it also controlled the acute phase response intensity in their offspring. Therefore the vaccination of dams may provide additional antibody protection against infection to their offspring.  相似文献   
10.
The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO3 or copper nanoparticles). Replacing the CuCO3 supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO3 with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain.  相似文献   
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