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1.
Phthalates such as di‐n‐butyl phthalate (DBP) and their esters are widely used plasticizers, their ubiquitous presence in daily life, inevitably leads to their restricted use due to important environmental pollution and health impacts and endocrine disruption potential. The aim of this study was to examine the effects of a sublethal concentration of 10 mg L?1 DBP on haematocrit (HCT) values, gills and liver histology, malondialdehyde (MDA, 2‐thiobarbituric acid‐TBA reactivity) and reduced glutathione (GSH) levels in gills and liver tissue as oxidative stress biomarkers in the aquaculture fish species Nile tilapia (Oreochromis niloticus) after 24 (DBP‐24) and 96 (DBP‐96) h exposure. No differences were found between per cent HCT values in the 24 h exposure groups (P > 0.05). Response of antioxidant defence systems in liver and gill tissues of the fish were dependent on exposure duration and changed to a higher extent during 96 h. MDA levels in liver tissue increased in DBP treated fish in comparison to the control fish. However, the differences between the exposure and control groups were not significant (P > 0.05). A statistically significant decrease (P > 0.05) was recorded in gill MDA levels in the DBP‐96 group when compared to the control and DBP‐24 groups. The liver GSH levels were unchanged in the DBP treated fish. However, GSH levels were significantly lower in the gill tissue of the DBP‐96 group. Exposure to DBP caused several degenerative changes in the histology of gill and liver tissue. Gills displayed hyperaemia, epithelial lifting, oedema, talengiectasia, epithelial hyperplasia and fusion of secondary lamellae, whereas in liver several circulatory anomalies (hyperaemia, blood congestion and sinosoid dilatation) and vacuolization of hepatocytes were observed. Histopathological results demonstrated that the gills were more affected than the liver perhaps due to their direct contact with DBP.  相似文献   
2.
Glutathione S-transferase (GST) from the liver and gill tissues of A?r? Bal?k Lake Trout (also known as Black Sea Trout) Salmo trutta labrax was characterized and purified, and the toxic effects of some heavy metal ions on the enzyme's activity were analyzed. Liver GST was purified 930 times, resulting in 56% yield using glutathione–agarose affinity chromatography and a specific activity of 60.87 endotoxin units (EU)/mg protein. Using the same procedure, gill GST was purified 576 times, resulting in a 60% yield and specific activity of 46.8 EU/mg protein. The purity check of the purified enzymes was determined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Optimal pH, ionic strength, and stable pH were found for each tissue, and separate KM and Vmax values were determined for reduced glutathione and 2,4-dinitrochlorobenzene substrates. Heavy metal ions that have toxic effects on living organisms and are known to contribute to environmental pollution were selected, and their in vitro effects on enzyme activity were analyzed. The IC50 values and Ki constants of those metal ions showing an inhibitory effect on GST activity were determined.

Received November 24, 2014; accepted March 11, 2015  相似文献   
3.
Meral GE  Konyalioglu S  Ozturk B 《Fitoterapia》2002,73(7-8):716-718
The essential oil of Turkish endemic Ziziphora taurica subsp. cleonioides aerial parts was found to contain (+)-pulegone (81.86%), limonene (4.48%) and piperitenone (2.30%) activity. The essential oil showed relevant antioxidant activity.  相似文献   
4.
Veterinarians and veterinary technicians are at risk for occupational brucellosis. We described the risk factors of occupational brucellosis among veterinary personnel in Turkey. A multicenter retrospective survey was performed among veterinary personnel who were actively working in the field. Of 712 veterinary personnel, 84 (11.8%) had occupational brucellosis. The median number of years since graduation was 7 (interquartile ranges [IQR], 4–11) years in the occupational brucellosis group, whereas this number was 9 (IQR, 4–16) years in the non-brucellosis group (p < 0.001). In multivariable analysis, working in the private sector (odds ratio [OR], 2.8; 95% confidence interval [95% CI], 1.55–5.28, p = 0.001), being male (OR, 4.5; 95% CI, 1.05–18.84, p = 0.041), number of performed deliveries (OR, 1.01; 95% CI, 1.002–1.02, p = 0.014), and injury during Brucella vaccine administration (OR, 5.4; 95% CI, 3.16–9.3, p < 0.001) were found to be risk factors for occupational brucellosis. We suggest that all veterinary personnel should be trained on brucellosis and the importance of using personal protective equipment in order to avoid this infection.  相似文献   
5.
1. This study aimed to evaluate the effects of juniper oil on growth performance and meat quality in quails to determine its use as a safe and natural method to reduce overdependence on the use of antibiotic.

2. A total of 1000 1-d-old Pharaoh (Coturnix coturnix Pharaoh) quails, including both males and females, were divided into 4 groups containing 250 quails and treated as follows: (1) a control group with 0 mg volatile oil/kg diet; (2) 100 mg/kg juniper oil; (3) 150 mg/kg juniper oil and (4) 200 mg/kg juniper oil. The diets were prepared fresh for each treatment. The experiment was carried out for 42 d.

3. The results of the study showed that supplementation with juniper oil (100 and 150 mg/kg) caused a significant increase in live weight, live weight gain and carcass yields during the growing and finishing periods. Feed intake and feed conversion ratio were not significantly influenced by treatments.

4. The quails given rations containing juniper oil had reduced thiobarbituric acid levels in raw thigh meat samples at different storage times. Juniper oil was found to have significant antioxidant activity and prevented lipid oxidation in stored meat.

5. In conclusion, natural antioxidants such as a juniper oil can be used instead of synthetic antioxidants to retard lipid oxidation in animal diets to improve meat product quality and animal performance.  相似文献   

6.
The aim of this study was to determine the pharmacokinetics/pharmacodynamics of enrofloxacin (ENR) and danofloxacin (DNX) following intravenous (IV) and intramuscular (IM) administrations in premature calves. The study was performed on twenty‐four calves that were determined to be premature by anamnesis and general clinical examination. Premature calves were randomly divided into four groups (six premature calves/group) according to a parallel pharmacokinetic (PK) design as follows: ENR‐IV (10 mg/kg, IV), ENR‐IM (10 mg/kg, IM), DNX‐IV (8 mg/kg, IV), and DNX‐IM (8 mg/kg, IM). Plasma samples were collected for the determination of tested drugs by high‐pressure liquid chromatography with UV detector and analyzed by noncompartmental methods. Mean PK parameters of ENR and DNX following IV administration were as follows: elimination half‐life (t1/2λz) 11.16 and 17.47 hr, area under the plasma concentration–time curve (AUC0‐48) 139.75 and 38.90 hr*µg/ml, and volume of distribution at steady‐state 1.06 and 4.45 L/kg, respectively. Total body clearance of ENR and DNX was 0.07 and 0.18 L hr?1 kg?1, respectively. The PK parameters of ENR and DNX following IM injection were t1/2λz 21.10 and 28.41 hr, AUC0‐48 164.34 and 48.32 hr*µg/ml, respectively. The bioavailability (F) of ENR and DNX was determined to be 118% and 124%, respectively. The mean AUC0‐48CPR/AUC0‐48ENR ratio was 0.20 and 0.16 after IV and IM administration, respectively, in premature calves. The results showed that ENR (10 mg/kg) and DNX (8 mg/kg) following IV and IM administration produced sufficient plasma concentration for AUC0‐24/minimum inhibitory concentration (MIC) and maximum concentration (Cmax)/MIC ratios for susceptible bacteria, with the MIC90 of 0.5 and 0.03 μg/ml, respectively. These findings may be helpful in planning the dosage regimen for ENR and DNX, but there is a need for further study in naturally infected premature calves.  相似文献   
7.
The serum concentrations of serotonin and lipids--triglycerides, total cholesterol, low density lipoprotein, high density lipoprotein and very low density lipoprotein--were determined in 18 normal dogs and 23 dogs diagnosed as aggressive on the basis of interviews with their owners and an assessment of their behaviour with reference to a canine overt aggression chart. The serum serotonin levels in the aggressive dogs were significantly lower than in the normal dogs (P<0.01), but the differences in serum lipids between the two groups were not statistically significant.  相似文献   
8.
This experiment was carried out to determine the effect of short-term hypothermia on blood malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glucose-6-phosphate dehydrogenase (G-6-PD) concentrations in rats. Twenty Sprague-Dawley rats were used weighing 180-200 g and on average 3.5 months old. They were randomly divided into two experimental groups: control (without cooling) and hypothermic (with cooling). The rats of the hypothermic group were cooled by immersion into cold water (10-12 degrees C), and the control rats were immersed into water of body temperature (37 degrees C) up to the neck without using any anaesthetic or tranquilizer for 3 min Rectal body temperatures of both groups were measured and blood samples to analyse MDA, GSH, SOD, GSH, GSH-Px and G-6-PD were collected immediately after the treatment. It was found that the MDA level was higher and the GSH and G-6-PD levels were lower in the hypothermic group than those in the controls. There was no difference between the control or hypothermic group regarding SOD or GSH-Px levels. It is concluded that acute hypothermia increased the lipid peroxidation and decreased the GSH and G-6-PD levels in rats.  相似文献   
9.
The objective of this study was to evaluate the effects of seven nitrogen (N2)-fixing and/or phosphorus (P)-solubilizing and siderophore-producing microorganism based bio-fertilizers in single and triple strain combinations isolated from the acidic rhizospheric soil of native tea, grapevine, and wild red raspberries. As a result of this study, bacterial efficiency was found to be variable and depended on the bacterial strains and evaluated growth parameters. Plant growth-promoting rhizobacteria (PGPR) has improved macro- and micro-nutrient concentrations in grapevine leaves, and stimulated plant growth. Triple inoculation and single inoculation based bio fertilizers were found to stimulate overall plant growth, including shoot and leaf weight, main shoot length, leaf ground index, chlorophyll, nitrogen, zinc and iron content of grapevine cv ‘Italy’. Bio-fertilizers increased the nutrients such as nitrogen, zinc and iron concentrations and consequently increased the chlorophyll content of the leaves.  相似文献   
10.
Electromagnetic shielding has a very emerging role in the textile applications. Screen-printing is a well-known, easy and cost effective process for textile printing. In this study, carbon black and graphite particles were used to impart electromagnetic shielding property to polyester fabric by screen printing technique. To this aim, printing pastes containing carbon materials were prepared with different binder concentrations. The electrical resistance, surface morphology, color coordinates and washing fastness properties of screen printed polyester fabrics were investigated. The washing durability of electromagnetic shielding effectiveness of carbon based printed fabrics as a function of binder concentration have also been studied. Electromagnetic shielding effectiveness was evaluated in the frequency ranges between 15-3000 MHz. The results showed that the electromagnetic shielding properties of fabric were affected by increased binder concentration. The most durable electromagnetic shielding effectiveness after washing process was obtained at highest binder concentration. The surface morphologies and color difference values of printed fabrics after washing process also provided a positive contribution.  相似文献   
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