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1.
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   
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Some of the properties of particleboard made from paulownia   总被引:3,自引:0,他引:3  
The objective of this study was to determine some of the properties of experimental particleboard panels made from low-quality paulownia (Paulownia tomentosa). Chemical properties including holocellulose, cellulose, lignin contents, water solubility, and pH level of the wood were also analyzed. Three-layer experimental panels were manufactured with two density levels using urea–formaldehyde as a binder. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), screw-holding strength, thickness swelling, and surface roughness of the specimens were evaluated. Panels with densities of 0.65 g/cm3 and manufactured using a 7-min press time resulted in higher mechanical properties than those of made with densities of 0.55 g/cm3 and press times of 5 min. Based on the initial findings of this study, it appears that higher values of solubility and lignin content of the raw material contributed to better physical and mechanical properties of the experimental panels. All types of strength characteristics of the samples manufactured from underutilized low-quality paulownia wood met the minimum strength requirements of the European Standards for general uses.  相似文献   
4.
Pneumonia is a leading cause of loss to ruminants throughout the world. Mannheimia (Pasteurella) haemolytica is one of the most important etiological agent of pneumonia in cattle, sheep, and goats. This study was carried out to determine the incidence of M.haemolytica antigens using immunohistochemistry labelling of formalin-fixed, paraffin-embedded tissues in pneumonic lungs of goats slaughtered at abattoir, and then to compare these immunohistochemistry results with the results of bacterial isolation. For these objectives, a total of 1505 goat lungs slaughtered in slaughterhouse were grossly examined and pneumonia was detected in 74 cases (4.91%). Of these, with the exception of verminous pneumonia observed in 32 cases, on 42 pneumonic lungs immunohistochemical examinations were performed. Formalin-fixed and paraffin-embedded lung tissue samples were immunohistochemically stained by the avidin-biotin-peroxidase complex (ABC) procedure using polyclonal antibodies to detect M.haemolytica antigens. Pneumonic lesions were more frequently encountered in cranioventral lobes than caudal lobes, and characterized by irregular lobular foci of atelectasis or lobar pneumonia. The presence of M.haemolytica antigens was detected in 19 (45%) out of 42 pneumonic lungs. Bacterial antigens were found most frequently in the cytoplasm of bronchial and bronchiolar epithelial cells, in the swirling degenerating leukocytes in the alveoli, and in the degenerating leukocytes in the area of coagulation necrosis, less frequently in the epithelial cells of bronchial glands, and lymphoid cells. Conclusionly, immunohistochemical detection of M.haemolytica antigens in pneumonic lungs appear to be more reliable compared to bacterial isolation.  相似文献   
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A case of aspergillosis in a broiler breeder flock having respiratory and nervous system problems caused by Aspergillus fumigatus and Aspergillus niger is documented. Dyspnea, hyperpnea, blindness, torticollis, lack of equilibrium, and stunting were observed clinically. On postmortem examination of the affected birds, white to yellow caseous nodules were observed on lungs, thoracic air sacs, eyes, and cerebellum. Histopathologic examination of lungs and cerebellum revealed classic granulomatous inflammation and cerebellar lesions, necrotic meningoencephalitis, respectively. No lesions were noted in the cerebrum histopathologically. Aspergillus hyphae were observed in stained sections prepared from lesioned organs. Fungal spores and branched septate hyphae were observed in direct microscopy. Aspergillus fumigatus and A. niger were isolated from the inoculations prepared from the suspensions of organs showing lesions.  相似文献   
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Rotenone, an insecticide, causes toxicity through inhibition of mitochondrial electron transport chain at complex I and oxidative injury to the tissues. The aim of the present study was to determine in vivo effects of rotenone on myocardium and cardio-protective effects of caffeic acid phenethyl ester (CAPE), an antioxidant agent, against rotenone toxicity in rats. The rats were divided into three groups: untreated control, rotenone (2.5 mg/kg/day for 60 days, i.p.) and rotenone + CAPE groups. CAPE was administrated i.p. 10 μmol/kg/day for 62 days started two days before first dose rotenone injection. The malondialdehyde, nitric oxide levels and xanthine oxidase activity of rotenone group was significantly higher than control and rotenone + CAPE groups (p < 0.05). However, catalase activity in the rotenone group was decreased in comparison with the other groups (p < 0.05). The superoxide dismutase activity of rotenone group was insignificantly decreased compared to the others. In conclusion, rotenone caused lipid peroxidation in myocardial tissue and CAPE treatment prevented this rotenone-induced lipid peroxidation in rats. CAPE might be a cardio-protective agent against myocardial toxicities.  相似文献   
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A disease outbreak occurred during the Spring of 2006 among rainbow trout, Oncorhynchus mykiss, kept in growout tanks. During the outbreak 35% of the rainbow trout died. Typical clinical signs were ulceration on the dorsal surface of the fish. Based on biochemical characteristics and sequence of 16S rRNA, the causative bacteria isolated from diseased fish were identified as Pseudomonas putida. Histologically, skin ulcer initially was characterized by sloughed off epithelia and epithelial necrosis. In the advanced form of the disease, almost all layers of the skin down to the epidermis were lost. Outside of Japan, this study reports the first P. putida infection in fish.  相似文献   
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Bacterial canker is an economically important disease of tomato. Resistance induced by DL-β-Amino butyric acid against bacterial canker caused by Clavibacter michiganensis ssp. michiganensis in tomato plants was investigated. Different doses of DL-β-Amino butyric acid (250–1000 μg ml−1 doses) were tested on 3-week old plants inoculated with a 108 CFU ml−1 bacterial suspension, and disease development was evaluated after inoculation and treatment. Although in vitro growth of the bacteria was not affected by DL-β-Amino butyric acid treatment, foliage sprays of 500 μg ml−1 DL-β-Amino butyric acid significantly suppressed disease development up to 54% by day 14 after inoculation at the four different doses tested. Bacterial populations were reduced by 84% in BABA-treated plants compared to water-treated plants by day 4 after inoculation. Inoculated BABA-treated plants showed significantly higher phenylalanine ammonia-lyase activity, peroxidase activity, and H2O2 concentration than inoculated water-treated plants during day 1 after treatment. These findings suggest that the DL-β-Amino butyric acid treatment resulted in an increase of these enzymes and in H2O2 concentration in planta, and was associated with induction of resistance to bacterial canker.  相似文献   
9.
Aluminum and iron were measured in daily samples collected at urban and rural sites near Ft. Myers, Florida, in 1995–1996 using a dichotomous sampler. Al and Fe concentrations were low during most of the year but they increased dramatically duringsummer when African dust was advected into Florida. The ratioof fine (less than 2.5 m diameter) to coarse (2.5–10 m) Al and Fe is relatively constant in African dust events with the fine accounting for a third to a half of the total. Also the mass ratio of Al-to-Fe is relatively constant at 1.8, a value similar to average crustal material. In contrast, in non-African dust the fine-to-coarse and Al-to-Fe ratios are extremely variable and generally much lower than those duringAfrican events when dust concentrations ranged up to 86 g m-3. The timing and magnitude of the Ft. Myers dust peaks closely matched those measured concurrently in Miami, 200 km to the southeast. Large areas of the eastern United States are frequently impacted by African dust every summer. Although dustconcentrations can reach very high values it seems unlikely that African dust events alone will cause a violation of the Environmental Protection Agency's standards for PM 2.5 or PM 10. However, African dust in conjunction with emissions from local and regional sources could conceivably present a problemwith compliance. The probability of such an occurrence is heightened by the fact that dust concentrations are highest in the summer when pollution levels are often at a maximum in theeastern states.  相似文献   
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Changes in the volatile composition during maturation and artificial ripening of yellow-fleshed nectarines were investigated by means of GC-FID and GC-MS over three years (1999-2001). Unripe and commercially ripe fruits were placed in ripening chambers until complete ripening and compared to tree-ripe nectarines. Firmness, weight, soluble solids (SS), titratable acidity (TA), SS/TA ratio, organic acids, and sugars were also determined. Furthermore, the tree-ripe and artificially ripened yellow-fleshed nectarines were subjected to sensory analysis by a taste panel. In 2001, a similar experiment on white-fleshed nectarines (cv. Vermeil) was performed to compare with the results obtained on yellow-fleshed nectarines. Levels of volatiles compounds, in particular, lactones and C(13) norisoprenoids, were found to be the same or higher in the artificially ripened nectarines compared with the tree-ripe nectarines. In addition, no significant difference was observed for sweetness, sourness, and the intensities of "peach odors" or "peach aroma" in the sensory analysis between the tree-ripe samples and the artificially ripened nectarines. However, in the latter the levels of SS and the SS/TA ratio were very close to those observed in the initial unripe samples and significantly lower than those observed in tree-ripe nectarines.  相似文献   
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