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1.
Effects of sodium nitroprusside (SNP; nitric oxide donor) treatments on enhancement of secondary metabolites production, oxidative stress mediators (\(\mathrm{O}_{2}^{-}\)) accumulation and antioxidant defense enzymes of Potato Spunta Sp. suspension culture cells elicited by a fungal extract from phytophthora infestans mycelium. The obtained data confirmed the significant increase in various oxidative burst (super oxide anion, hydrogen peroxide and total glutathione) contents. The administration of various NO concentrations strongly decreased hydrogen peroxide concentration and superoxide anion levels. Moreover, the SNP treatments regulate elicitor-induced activation of phenylalanine ammonium-lyase and total soluble phenols accumulation. The highest concentrations of NO donor sodium nitroprusside potentiated elicitor-induced H2O2 production. On the other hand, the lowest H2O2 contents coincided with elicitation regulated various activities of enzymes superoxide-dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and Phenyl alanine ammonia lyase (PAL) activity, the decrease in H2O2 concentration was probably due to a direct reduction interaction of NO-H2O2. On the other hand, the addition of these previous NO treatments affects mRNA peroxidase gene expression using RT-PCR techniques. In general, the addition of lower concentrations of nitric oxide reduce the mRNA peroxidase activity on contrary, the higher concentrations induced the mRNA peroxidase activity, which induce the hypersensitive reactions against fungus infection.  相似文献   
2.
ABSTRACT

A 24-week feeding trial was conducted in concrete tanks with Nile tilapia, Oreochromis niloticus (L.) with an average initial weight and length of 50.87 ± 6.03 g and 14.4 ± 0.45 cm, respectively, to examine the effect of two protein sources and two feeding frequencies on growth performance, production traits, and body composition. Twelve 4 m3 concrete tanks (2 × 2 × 1.25 m, long, width, and height) were each stocked with 100 fish and fed diets containing either fish meal protein or soybean meal protein at two feeding frequency of two times daily or four times daily (2 × 2 × 3 factorial experiment). The results revealed that there was no significant effect of dietary protein sources on growth rate, whereas there was a significant increase in growth rate with increasing feeding frequency (P < 0.05). The same trend was also observed for mean body weight (g), production rate (kg/m3), specific growth rate (SGR % day?1). The best final mean body weight (g), specific growth rate (SGR % day?1), and production rate (kg/m3) were recorded in groups of fish fed with feeding frequency four times daily. Whole fish moisture, protein, fat, and ash contents were significantly influenced (P ≤ 0.05) by protein sources and feeding frequency, except protein not influenced with feeding frequency. Energy was significantly (P < 0.05) influenced by feeding frequency, but not by dietary protein sources. Economic evaluation indicated that soybean meal (Diet B) at four times feeding daily was the most cost-effective and affordable feed strategy for farmers. We conclude that a soybean diet fed four times daily is recommended for adult Nile tilapia reared in concrete tanks.  相似文献   
3.
Laryngeal paralysis in dogs: a review of 23 cases   总被引:1,自引:0,他引:1  
The medical records of 23 dogs with laryngeal paralysis were reviewed. Although the condition developed mainly in old, large- or giant-breed dogs, a wide range of breeds was involved. The age of affected animals ranged from 7 months to 14 years. Respiratory distress, exercise intolerance, noisy breathing, and hoarse bark were common signs of the paralysis. Laboratory evaluations for hypothyroidism were performed on 11 dogs; only 3 were judged to have primary hypothyroidism. Males, particularly if castrated, were more frequently affected than females. A neurologic examination was performed on 6 dogs; 4 of them were found to have generalized neuromuscular disease.  相似文献   
4.
Abstract— A12-wk feeding experiment was conducted to study the feasibility of utilizing cluster bean seed meal (CBM) as a replacement for fishmeal in the diets for common carp Cyprnus carpio fingerlings. The replacement levels of cluster bean meal protein in the diets were 25, 50, 75, and 100% of the total fishmeal protein. All diets were isonitrogenous at 33.1% crude protein and isocaloric at 4.8 Kcal/g. There were significant differences in the final individual weights, weight gains, specific growth rates (SGR %/d), feed conversion ratios (FCR), feed efficiency ratio (FER), protein efficiency ratios (PER), and feed intake among fish group ( P × 0.05). Common carp fed the diet containing 50% (CBM) exhibited comparable growth to those fed a fishmeal-based diet. Digestibility of protein, energy and lipid decreased with increasing levels of CBM above 50% of total fishmeal replacement in the diet. Incorporation of CBM in diets significantly affected the dry matter, protein, and energy of whole fish body. These results suggest that CBM can replace 50% of the fishmeal in diet for common carp.  相似文献   
5.
Wind erosion force vectors were computed from data of frequencyof occurrence of windspeed and direction based on the assumptionthat wind erosion is proportional to (windspeed)3× duration of exposure.The vertical distribution of eroded soil material wasmathematically described. The transition height betweensaltation and suspension could be identified and used tointegrate the two equations describing saltation and suspension.The soil avalanching process was studied by evaluating the horizontal changes of eroded soil material. The vertical andhorizontal distribution of eroded soil constituents, i.e.,particle size distribution, mean weight diameters, plantnutrients and heavy minerals content for selected wind stormswere also evaluated. Results revealed that soil constituents change considerably with the height and downwind distance.To assess the changes in soil properties due to wind erosion,surface soil samples were taken from the original eroded surfaceand from freshly accumulated drifts near the eroded field.Enrichment ratios were more than one for the fine fraction, organic matter, moisture retention, and chemical constituentsindicating a loss in their contents in the eroded field.  相似文献   
6.
Mycobacterium avium subsp. paratuberculosis (Map), the etiologic agent of Johne's disease (JD) in ruminants, has been implicated in the pathogenesis of Crohn's disease (CD) in humans. We developed a bovine ileal cannulation model to facilitate comparison of the immune response to Map and the mechanisms of pathogenesis in cattle and humans. Initial studies showed a T cannula could be maintained for up to a year in calves without inducing inflammation or adversely affecting intestinal function. Map introduced through the cannula established a persistent low level of infection without inflammation. Infection elicited an immune response to Map antigens detectable by flow cytometry. Further studies now show the cannulation model can be used with cows during the later stage of infection, affording access to the target tissue at all stages of infection. The studies also revealed no difference in infectivity or immunogenicity of isolates of Map obtained from cattle or humans with CD. Comparison of the immune response to Map during the early and late stages of infection using PCR, flow cytometry and QRT-PCR, showed the immune response early in the disease process is dominated by CD4 T cells. A CD8 response is delayed but comparable at later stages of infection. Genes for pro-inflammatory cytokines IFN-γ and the recently identified genes encoding IL-17 and IL-22 are up regulated in infected animals. These findings reveal that both human and bovine isolates of Map can establish infection and induce similar immune responses in a bovine model. They also reveal the cytokine responses elicited in cattle are similar to those implicated in CD pathogenesis.  相似文献   
7.
Field trials were carried out from 2008 to 2011 at Maribor, Slovenia to determine the effect of new copper fungicide formulations on the copper content in apple fruits, separated in peel and flesh, of seven cultivars at harvest. Apple trees were treated 12?C18 times per season with formulations based on copper oxychloride or sulphate (trial standards), copper hydroxide and their complexes or chelates with amino acids, peptides, EDTA, urea, and octanoic or gluconic acids at the same rate of 200?g of pure copper ions (Cu2+) per hectare irrespetive of the product. Copper formulations were applied with Teejet 800067 flat fan nozzles mounted on a vertical boom of the sprayer, which gave a droplet volume median diameter (VMD) of 120 microns and 130?C180 droplet impacts per square centimeter, as determined on water sensitive papers. The new formulations of copper in the form of salts of fatty acids or organic complexes or chelates had a higher penetration rate into apple fruit tissue than the traditional formulations based on Cu-hydroxide, Cu-oxychloride and Cu-sulphate. The copper content in the fruit depended on the ratio between copper solubility in the formulation, rate of penetration into the fruit and stability of the copper fungicide deposit on the fruit surface. Despite being applied at lower hectare rates, frequent applications led to the exceeding of the permitted EC maximum residue level of 5?mg/kg fresh mass (FM). MRL was most often exceeded with the application of formulations based on Cu-octanoate and Cu-gluconate and less often in case of the application of complexes of copper with amino acids, peptides or urea. A comparison of the copper content between different cultivars showed that cv. ??Jonagold??, ??Golden Delicious?? and ??Elstar?? accumulated more cooper than other cultivars. Copper concentrations in the peel exceeded that of the flesh at least twice. The potential effects of accumulation of copper in woody tissue of bearing shoots after long-term application of highly systemic copper formulations on growth and blooming of apples are discussed too. Some apple growers may not be aware of much higher penetration rate of these new copper products (fungicides, fertilisers or plant strengtheners) and should be warned about the necessity to adapt their spraying schedules despite applications of a low hectare rates of copper, i.e. the number of treatments and proper seasonal timing, to avoid exceeding of EU MRL of copper in fruit.  相似文献   
8.
Ambient UV radiation is recognised as an important environmental factor in the regulation of plant growth and development, and selenium (Se) as a beneficial nutrient that can increase plant tolerance to different environmental constraints. The effects on hybrid buckwheat plants of full (+UV) and reduced (?UV) ambient UV radiation without (?Se) and with (+Se) foliar Se treatment (10?mg?L?1 sodium selenate) provided the four conditions of Se?UV–, Se–+UV, +Se?UV and +Se+UV. Plant morphological, biochemical and physiological properties were examined, along with leaf elemental composition and content, efficiency of Se enrichment, and production parameters. Leaf anatomical parameters under all conditions were mainly affected by UV radiation, and less so by Se. +Se+UV plants showed a trade-off between primary and secondary metabolism, which resulted in high levels of protective substances (e.g. anthocyanins, UV absorbing compounds), and low levels of photosynthetic pigments. All +UV plants were significantly shorter in comparison to those under the reduced ?UV, while biomass production was highest for ?Se+UV plants and lowest for +Se+UV plants. +Se plants accumulated ~20-fold greater Se content compared to ?Se plants, and full ambient UV radiation partly reduced this effect. +UV plants showed increased phosphorus content in leaves, independent of Se status, while +Se plants showed increased K content. Si content was increased by Se treatment and decreased by the full UV exposure. Se treatment and the ambient UV radiation, separately have positive effects on growth and production of this hybrid buckwheat, while the combination of the Se treatment and ambient UV resulted in lower yields. However, under these conditions (+Se+UV), the buckwheat plants established good protection against the different environmental constraints that are becoming more and more frequent due to changes to our climate.  相似文献   
9.
Recommendations are presented for standardized imaging planes and display conventions for two-dimensional echocardiography in the dog and cat. Three transducer locations ("windows") provide access to consistent imaging planes: the right parasternal location, the left caudal (apical) parasternal location, and the left cranial parasternal location. Recommendations for image display orientations are very similar to those for comparable human cardiac images, with the heart base or cranial aspect of the heart displayed to the examiner's right on the video display. From the right parasternal location, standard views include a long-axis four-chamber view and a long-axis left ventricular outflow view, and short-axis views at the levels of the left ventricular apex, papillary muscles, chordae tendineae, mitral valve, aortic valve, and pulmonary arteries. From the left caudal (apical) location, standard views include long-axis two-chamber and four-chamber views. From the left cranial parasternal location, standard views include a long-axis view of the left ventricular outflow tract and ascending aorta (with variations to image the right atrium and tricuspid valve, and the pulmonary valve and pulmonary artery), and a short-axis view of the aortic root encircled by the right heart. These images are presented by means of idealized line drawings. Adoption of these standards should facilitate consistent performance, recording, teaching, and communicating results of studies obtained by two-dimensional echocardiography. (Journal of Veterinary Internal Medicine 1993; 7:247–252. Copyright © 1993 by the American College of Veterinary Internal Medicine.)  相似文献   
10.
Recommendations are presented for standardized imaging planes and display conventions for two-dimensional echocardiography in the dog and cat. Three transducer locations (“windows”) provide access to consistent imaging planes: the right parasternal location, the left caudal (apical) parasternal location, and the left cranial parasternal location. Recommendations for image display orientations are very similar to those for comparable human cardiac images, with the heart base or cranial aspect of the heart displayed to the examiner's right on the video display. From the right parasternal location, standard views include a long-axis four-chamber view and a long-axis left ventricular outflow view, and short-axis views at the levels of the left ventricular apex, papillary muscles, chordae tendineae, mitral valve, aortic valve, and pulmonary arteries. From the left caudal (apical) location, standard views include long-axis two-chamber and four-chamber views. From the left cranial parasternal location, standard views include a long-axis view of the left ventricular outflow tract and ascending aorta (with variations to image the right atrium and tricuspid valve, and the pulmonary valve and pulmonary artery), and a short-axis view of the aortic root encircled by the right heart. These images are presented by means of idealized line drawings. Adoption of these standards should facilitate consistent performance, recording, teaching, and communicating results of studies obtained by two-dimensional echocardiography.  相似文献   
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