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José A. Vázquez Lorenzo Pastrana Carmen Pi?eiro José A. Teixeira Ricardo I. Pérez-Martín Isabel R. Amado 《Marine drugs》2015,13(10):6537-6549
This work investigates the production of hyaluronic acid (H) by Streptococcus equi subsp. zooepidemicus in complex media formulated with peptones obtained from Scyliorhinus canicula viscera by-products. Initially, in batch cultures, the greatest productions were achieved using commercial media (3.03 g/L) followed by peptones from alcalase hydrolyzed viscera (2.32 g/L) and peptones from non-hydrolyzed viscera (2.26 g/L). An increase of between 12% and 15% was found in subsequent fed-batch cultures performed on waste peptones. Such organic nitrogen sources were shown to be an excellent low-cost substrate for microbial H, saving more than 50% of the nutrient costs. 相似文献
114.
Carmen Gómez-Lama Cabanás Encarnación Pérez-Artés 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(3):445-451
Fusarium oxysporum f. sp. dianthi (Fod) causes vascular wilt, the most important carnation disease worldwide. We have analyzed vegetative compatibility in a collection of Fod isolates, obtained from both soils and carnation plants in the most important growing areas in Spain, by pairing all isolates in all possible combinations. Results showed that isolates of race 1 and race 2 were distributed among three Vegetative Compatibility Groups (VCG) which correlated with the molecular Groups previously described. Isolates of race 1 and race 2 in molecular Group I grouped in VCG 0021, isolates of race 1 type were in VCG 0022, and isolates of race 1 and race 2 in molecular Group II constituted a new VCG (002-), not previously reported. Isolates in each VCG contained the same mating type gene (MAT1-1 or MAT1-2), with the exception of the new VCG 002- that contained both idiomorphs. This work identifies a new VCG in Fod populations and reports for the first time the presence of isolates of race 1 and race 2 in the same VCG. 相似文献
115.
Tracy Miesner David Wilkie† Anne Gemensky-Metzler‡ Steven Weisbrode§ Carmen Colitz¶ 《Veterinary ophthalmology》2009,12(4):263-268
At The Ohio State University from 1994–2006 six of seven horses evaluated for primary orbital disease were diagnosed with extra-adrenal paraganglioma (EAPG). The horses ranged in age from 14 to 24 years, with a mean of 16.8 years. Duration of clinical signs was 1.5 years to 5 years, with a mean of 2.8 years. Clinical signs varied, but all six had non-painful exophthalmus of the right eye. Five horses had complete ocular exams reported; three of five had decreased to absent vision, two of five had pale optic nerves, and in three of five, difficulty of retropulsion of the globe was noted. Diagnostic tests performed included complete blood count, serum profile, radiography, ultrasound, computed tomography, true-cut biopsy, ocular examination, guttural pouch endoscopy, oral examination, and physical examination. Expulsive hemorrhage during orbital exenteration occurred in all horses. In five of six cases, tumor extension through the orbital foramen was apparent intra-operatively. Histopathologic appearance of all surgically removed tissues consisted of sheets of polygonal cells with abundant lightly granular cytoplasm, round nuclei with vesicular chromatin, and rare mitoses. Neoplastic cells were arranged into small groups separated by a fine fibrovascular stroma. All six cases were chromagranin positive on immunohistochemical staining. Follow-up ranged from six months to six years, with a mean of two years. Four of the five horses that recovered from surgery had no apparent tumor recurrence in 6–48 months. 相似文献
116.
Carmen L. Battaglia 《Journal of Veterinary Behavior: Clinical Applications and Research》2009,4(5):203-210
It is not capacity that explains the differences that exist between individuals, because most seem to have far more capacity than they will ever use. The differences that exist between individuals seem to be related to something else. Researchers have studied these phenomena and have looked for new ways to stimulate individuals to improve their natural abilities. Some of the methods discovered have produced lifelong effects. Today, many of the differences between individuals can now be explained by the use of early stimulation methods, socialization, and enrichment experiences. For example, early life has been found to be a time when the physical immaturity of an organism is susceptible and responsive to a restricted but important class of stimuli. Because of its importance, many studies have focused on the first year of life. Newborn pups are different from adult dogs in several respects. When born, pups' eyes are closed, their temperature is subnormal, and their digestive system has a limited capacity, requiring periodic stimulation by their dam, who routinely licks them to promote digestion. Other mammals such as mice and rats are also born with limitations, and they also have been found to show a similar sensitivity to the effects of early stimulation. Studies show that removing them from their nest for 3 min each day during the first 5–10 days of life causes body temperatures to fall below normal. This mild form of stress is sufficient to stimulate hormonal, adrenal, and pituitary systems. When tested later as adults, these same animals were better able to withstand stress than littermates who were not exposed to the same early stress exercises. As adults, they responded to stress in “a graded” fashion, whereas their nonstressed littermates responded in an “all or nothing way.” The results show that early stimulation can have positive results but must be used with caution. Too much stress can cause pathologic adversities rather than physical or psychologic superiority. Socialization and enrichment experiences have also been found to make important differences in the development of the adult dog. 相似文献
117.
Marca MC Gómez-Quintero A Viñuales C Rodríguez-Yoldi MJ 《Veterinary journal (London, England : 1997)》2009,180(2):213-220
Lipopolysaccharide (LPS) is an endotoxin comprising part of the cell wall of Gram-negative bacteria. It is able to induce a septic state and the release of several pro-inflammatory cytokines that are known to be responsible for hormonal changes in humans and animals. The aim of this study was to evaluate changes in plasma adrenocorticotrophic hormone (ACTH), corticosterone and cortisol levels in a rabbit model in which sepsis was induced by the intravenous administration of LPS. The possible involvement of several protein kinases, namely protein kinase A (PKA), C (PKC) and mitogen-activated protein kinases (MAPKs), and proteasome was also assessed. The results indicated that LPS induced significant increases in plasma ACTH, corticosterone and cortisol concentrations in rabbits. Moreover, protein kinases and proteasome seemed to mediate the hormone response to LPS as treatment with specific inhibitors prior to LPS administration was able to reduce, delay, or, in some cases, inhibit the hormone increases. The findings may help to construct strategies to protect and treat animals with endotoxaemia. 相似文献
118.
Steffen Hoy Jrg Bauer Catrin Borberg Leonie Chonsch Carmen Weirich 《Livestock Science》2009,126(1-3):69-72
The investigations were carried out with 484 sows from two farms (farm A: housing the sows in small groups of 8 animals each, farm B with a large group of 100 sows) and a total number of 982 inseminations. The number of agonistic interactions was registered for each sow during 48 h after mixing soon after weaning the piglets at farm A. The individual rank place in the social hierarchy was calculated on the basis of wins and defeats and the sows were divided in high and low ranking sows. At farm B the rank position was estimated on the basis of the daily feeding order at two electronic feeding stations (first half of the sows in the feeding order = high ranking, second half = low ranking). Additionally, the following parameters were recorded for each sow: parity, genotype, farrowing rate and litter size (total and alive born piglets). The analysis showed that sows with a high rank position had a significantly higher farrowing rate (88.8%) compared to group-mates with low rank places (82.8%, p = 0.051) (farm A). Sows with a high rank position reached a significantly higher litter size of total born piglets (12.66, 16.14 piglets per litter respectively) than the low-ranking group-mates (12.13, 14.83 piglets/litter respectively — farms A and B). When mixing sows, the time and the conditions (e.g. group size, space allowance per sow) have to be considered to prevent the negative influence of low rank order on fertility. 相似文献
119.
Jorge Paz-Ferreiro Carmen Trasar-Cepeda Ma Carmen Leirós Socorro Seoane Fernando Gil-Sotres 《European Journal of Soil Biology》2010,46(2):136-143
Biochemical properties are considered to be the best indicators available at present for assessing soil quality. However, there are still many gaps in our knowledge about how these properties are affected by abiotic factors and how these factors interact with soil management. With the aim of understanding how climate and soil management affect soil biochemical properties in grasslands soils from a temperate-humid area (Galicia, NW Spain), a total of 60 soils were analyzed for several microbial and biochemical properties. Grasslands were divided into groups according to the type of management applied (native compared with intensive) and to the climate in the area where they were sampled (Mediterranean subhumid with centroeuropean drift climate compared with Atlantic climate). We found that management had a greater influence on soil biochemical properties than climate. Altitude, which strongly influences climate in the region where the soils were analyzed, was found to be a significant factor that affected most soil biochemical properties. In conclusion, the results show that microbially-mediated processes are greatly affected by both, management and abiotic factors and that, for some properties (like net N mineralization and cellulase and casein-protease activities), abiotic factors can have an important influence on soil biochemical properties. 相似文献
120.