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41.
The present study was designed to compare the responses in freshwater fish Oreochromis niloticus exposed to a synthetic pyrethroid, cypermethrin (CYP); an essential metal, copper (Cu); and a nonessential metal, lead (Pb). Fish were exposed to 0.05 μg/l CYP, 0.05 mg/l Cu, and 0.05 mg/l Pb for 4 and 21 days, and the alterations in serum enzyme activities, metabolite, and ion levels were determined. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities increased in response to CYP, Cu, and Pb exposures at both exposure periods. While elevations in alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities and in cholesterol level were observed in pesticide-exposed fish at 4 and 21 days, they increased in Cu- and Pb-exposed fish at 21 days. Although metal-exposed fish showed increases in cortisol and glucose levels at 4 days followed by a return to control levels at the end of the exposure period, their levels elevated in pesticide-exposed fish at both exposure periods. Total protein levels decreased in Pb- and pesticide-exposed fish at 21 days. Na+ and Cl levels decreased in pesticide-exposed fish at both exposure periods and in Cu- and Pb-exposed fish at 21 days. The exposures of pesticide and metals caused an elevation in K+ level at the end of the exposure period. The present study showed that observed alterations in all serum biochemical parameters of fish-treated pesticide were higher than those in fish exposed to metals.  相似文献   
42.
The objective of this study was to determine the effects of consecutive application of gypsum dissolved in leaching water on hydraulic conductivity of a saline‐sodic soil. Drainage type plastic columns with a 10 cm diameter were used in this laboratory experiment. Soil depth within columns was 30 cm with an average bulk density of 1.38 g cm–3. Leaching water was applied in six equal portions. Total gypsum was applied at 1, 3, and 5 portions after dissolving in leaching water. In dissolution, equal (1.273 + 1.273 + 1.273 Mg ha–1), increasing (0.637 + 1.273 + 1.910 Mg ha–1) and decreasing (1.910 + 1.273 + 0.637 Mg ha–1) quantities of gypsum were used. Results were compared with the control treatment, in which total amount of gypsum were mixed with surface layer of soil column before leaching. Hydraulic conductivity of soil increased in all treatments. The maximum hydraulic conductivity value was obtained at consecutive application of gypsum at decreasing quantities.  相似文献   
43.
This study was carried out to investigate the potential vectors and relative mosquito infection rates of Dirofilaria immitis throughout two mosquito seasons (2008-2009) in Kayseri province where is located in Central Anatolian part of Turkey. For this aim, totally 1198 genomic DNA pools, extracted and grouped according to the species and collection site (1-17 specimens/pool) from 6153 mosquito specimens, were examined by PCR using species-specific primers for D. immitis. The captured mosquitoes from 46 focuses were survived under in vitro conditions for 7 days to allow the development of larval stages of D. immitis. DNA extraction was performed individually to both thorax-head and abdomens in order to determine infective and infected mosquito specimens, respectively. The most abundant mosquito species in the study area was determined as Ae. vexans (51.7%) and this was followed by Cx. pipiens (42.1%), Cx. theileri (3.1%), Cs. annulata (1.5%), An. maculipennis (1.0%) and Cx. hortensis (0.6%). The PCR results indicated that 9/312 and 12/312 pools from Ae. vexans abdomens and thorax-heads were positive for filarial DNAs, respectively where as 3/241 pools of each abdomens and thorax-heads from Cx. pipiens were positive for D. immitis DNAs. The minimum infection rates (MIRs) for Ae. vexans and Cx. pipiens were calculated as 0.41 and 0.12, respectively. Although D. immitis DNA's were found in both pools from Ae. vexans and Cx. pipiens, the calculated MIRs provide evidence that Ae. vexans could be the main potential vector of D. immitis in Kayseri.  相似文献   
44.
The aims of this study were to demonstrate the effects of zinc sulphate administration (2 g/week p.o., 2% solution) on zinc, copper, iron, calcium and magnesium levels in blood serum of 20 pregnant Ivesi sheep during the last 2 month of pregnancy, immediately post partum as well as in their newborn lambs. In these 20 lambs, also total serum protein, gamma globulin and birth weight were determined. The control group consisted of 15 pregnant sheep and their 15 lambs housed under the same conditions. Zinc sulphate administered to sheep caused significant increases in their serum levels of zinc as well as in those of their lambs. The lambs of the zinc supplemented group had also slightly higher birth weights (not significant) and significant higher gamma globulin levels, whereas the total protein values was almost identical in both groups.  相似文献   
45.
One-day-old turkeys (Meleagris gallopavo) were orally inoculated with the intestinal contents of an adult turkey, and the intestinal tissues were studied by immunofluorescence for immunoglobulin (Ig)-bearing cells at 3, 7, 14, and 21 days of age. Microflora inoculation increased numbers of Ig-bearing cells in the gut-associated lymphoid tissues; the most uniform effects were observed at 3 days of age. As the birds grew older, this uniformity in response to the microflora inoculation was not evident in all the tissues. In the bursa of Fabricius and the large intestine of the inoculated birds, IgM-bearing cells were more numerous throughout the study period. Compared with noninoculated control turkeys, IgA-bearing cells in the cecal tonsils, and IgG- and IgA-bearing cells in the small intestine were increased at all age intervals.  相似文献   
46.
In this study, immunoreactive proteins (8, 68 and 116 kDa) of Echinococcus granulosus metacestode stages were partially purified using isoelectrical focusing by a Rotofor cell device. Sixty Swiss albino mice were separated into three experimental and three control groups (n = 10). The mice of the three experimental groups were immunized with 8, 68 and 116 kDa purified proteins, respectively. 25 days after immunization, serum samples from each group were examined to assess immunization status by Western blotting. Protoscolices were applied intraperitoneally to control and immunized groups. By necropsy, mice were examined for cyst formation, size, number and fertility 2, 5, 8, and 10 months after experimental infection, respectively. Immunization with all three proteins was found to have a significant inhibitory effect on the metacestode formation of in mice (p < 0.001).  相似文献   
47.
48.
Plant growth promoting effects of Alcaligenes 637Ca, Staphylococcus MFDCa-1, MFDCa-2, Agrobacterium A18, Pantoea FF1 and Bacillus M3 were tested on strawberry cv. ‘Aromas’ based on yield, number, and weight of fruit, leaf area, vitamin C, total soluble solids (TSS), acidity and ionic composition of leaves under calcareous soil conditions. The results demonstrated that all of bacterial treatments significantly affected all parameters tested. The best result was obtained from 637Ca treatment, which significantly increased fruit yield, number and weight about 47.5, 34.7, and 9.4%, respectively, compared to control. Except for magnesium (Mg) and zinc (Zn) in the leaf, the concentrations of all plant tissue nutrients [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), copper (Cu), manganese (Mn), boron (B)] were significantly increased by bacterial treatments tested. The data in the present study showed that all bacterial treatments including Alcaligenes 637Ca, Staphylococcus MFDCa-1, MFDCa-2, Agrobacterium A18, Pantoea FF1, and Bacillus M3 to strawberry plants can ameliorative the deleterious effect of high lime on fruit yield, growth and nutrition. These results suggested that plant growth-promoting Rhizobacteria (PGPR) treatments could be offer an economic and simple means to increased plant resistance for high calcareous soil conditions.  相似文献   
49.
1. The aim of the study was to describe the effect of Epigallocatechin-3-gallate (EGCG), a polyphenol derived from green tea, on activator protein-1 (AP-1) components (phospho-c-Jun and c-Fos), cyclooxygenase-2 (COX-2) and heat shock proteins (HSPs) in the liver of heat-stressed quails.

2. A total of 180 5-week-old female Japanese quails were reared either at 22°C for 24 h/d (thermoneutral, TN) or 34°C for 8 h/d (heat stress, HS) for 12 weeks. Birds in both environments were randomly given 1 of 3 diets: basal diet and basal diet with 200 or 400 mg of EGCG added per kilogram of diet.

3. The hepatic c-Jun, c-Fos, COX-2 and HSPs gene expression for quails reared under the HS environment was greater than those reared under the TN environment. Supplemental EGCG decreased hepatic expression of these proteins at a greater extent under HS than TN.

4. In conclusion, suppression of AP-1 COX-2 and HSPs may partly account for the inhibitory effect of EGCG in heat-stressed quail.  相似文献   

50.
Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efficiency (IWUE) of summer squash responses to different irrigation quantities were evaluated with a field study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefficients (Kcp, 100% (Kcp1), 85% (Kcp2) and 70% (Kcp3)). Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield (80.0 t ha−1) was determined in the Kcp1 treatment, which applied the highest volume of irrigation water (452.9 mm). The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha−1, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment (176.6 kg ha−1 mm−1), it was statistically similar to the value for Kcp3 treatment (157.1 kg ha−1 mm−1). Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 (44.27 μg gallic acid equivalents (GAE) mg−1 fresh sample) and in the Kcp2 (84.75%) treatments, respectively. Major (Na, N, P, K, Ca, Mg and S) and trace (Fe, Cu, Mn, Zn and B) mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were significantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions.  相似文献   
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