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81.
Bertagnolli AC Soares P van Asch B Amorim A Cirnes L Máximo V Cassali GD 《Veterinary journal (London, England : 1997)》2009,182(2):269-274
The aim of this study was to investigate if mutations in the mitochondrial DNA (mtDNA) D-loop fragment control region of canine mammary mixed tumours could be used as clonal markers that identified the cell population of origin. Ten benign mixed mammary tumours and nine carcinomas arising from benign mixed tumours were microdissected and DNA from epithelial and mesenchymal tumour cells and from normal mammary tissue was examined for sequence variations in a fragment of the hypervariable control region.Identical sequence variants in both the epithelial and mesenchymal components (as well as in the corresponding normal tissue) were found in 80% of the benign mixed tumours and in 89% of the carcinomas arising from benign mixed tumours suggesting a shared clonal origin. The distinctive sequence alterations identified in the epithelial and mesenchymal components of 15.8% of all 19 tumours examined, suggests the possibility that a minority of mammary tumours are polyclonal in origin or that early clonal divergence occurs. Increased mutation within the mtDNA D-loop fragment of mixed tumour components was not observed. 相似文献
82.
A histopathologic, immunohistochemical, and ultrastructural study of the trachea and the bronchi of 6 rabbits experimentally intoxicated with the calcinogenic plant Solanum glaucophyllum was performed. Histologically, infiltration of the mucosa and the submucosa of the trachea and the bronchi by macrophages, multinucleated giant cells, a few lymphocytes and mast cells, and calcium deposits in the basal lamina of the epithelium and in elastic fibers were observed. Expression of osteocalcin, osteonectin, and osteopontin was detected in the mucosa, lamina propria, and epithelium. Electron microscopic study of the corresponding areas showed numerous macrophages in the process of fusion to form multinucleated giant cells, activated mesenchymal cells, and calcium precipitation in the basal lamina of epithelium and in elastic fibers. It is suggested that the high levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in the plant induces macrophage proliferation, multinucleated giant-cell formation, mesenchymal cell activation, bone-protein synthesis, and calcification. In addition, the synthesis of 1,25(OH)2D3 by local macrophages may have contributed to the calcification. 相似文献
83.
Danilo Araujo Soares Pereira Marcelo Barbosa Henriques 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):428-448
AbstractThe L46 (Hypancistrus zebra) stands out as one of the most valuable Amazonian species in the international market for ornamental fish and faces a notable problem: the risk of extinction versus the demand for new specimens for aquariums. Considering that breeding in captivity can be a conservational tool for aquatic species and an alternative source for generating income, the objective of the present paper was to verify the economic feasibility of producing H. zebra in recirculation aquaculture systems (RAS), in different scenarios of rearing: residential breeding (S1), mid-size store production (S2) and large-scale production as a supplier (S3). The main profitability indicators used were: net present value (NPV), internal rate of return (IRR) and payback period (PP). The selling price per unit was fixed in US$260.15 (S1/S2) and US$156.09 (S3). The largest investments were made with the acquisition of broodstocks (S1/S2) and property (S3), while the highest costs were with labor (S2/S3) and taxes (S1). Only S1 demonstrated economic profitability (NPV 8.50%?=?US$28,187.85; IRR?=?74.71%; PP?=?1.80?years). Conclusion: the production in this study appeared to be profitable on smaller scales, however the profitability of large-scale production depends upon reducing expenses and increasing the selling price. 相似文献
84.
Juliana Aguiar Interaminense Nathalia Ferreira Calazans Bruna Critas do Valle Joana Lyra Vogeley Sílvio Peixoto Roberta Soares Jos Vitor Lima Filho 《Journal of the World Aquaculture Society》2014,45(1):65-74
Experiments were conducted to evaluate different prophylactic methods to control the bacterial load in brine shrimp, Artemia, hatching. The first experiment evaluated three treatments to control Vibrio spp. during the Artemia hatching: microalgae (Chaetoceros calcitrans), probiotic (Bacillus spp.), and antibiotic (Florfenicol). In the second experiment, Artemia metanauplius were enriched in distinct treatments with C. calcitrans, probiotic, and emulsion rich in docosahexaenoic and eicosapentaenoic fatty acids. Enriched Artemia metanauplius and nauplii (control) were offered to white shrimp, Litopenaeus vannamei, postlarvae (PL7–PL19). Presumptive Vibrio were quantified in Artemia, PL, and rearing water. Microalgae and probiotic were effective to control Vibrio spp. in Artemia nauplii. The enrichment process increased the Artemia bacterial load but did not affect Vibrio load in L. vannamei. 相似文献
85.
Caique Carvalho Medauar Samuel de Assis Silva Luis Carlos Cirilo Carvalho Rafael Augusto Soares Tibúrcio Julião Soares de Souza Lima Paullo Augusto Silva Medauar 《Journal of Sustainable Forestry》2018,37(7):739-752
This study evaluated the effectiveness of chemical control for eradicating eucalyptus sprouts using images obtained with Unmanned Aerial Vehicle (UAV). The study was carried out in eucalyptus plantations in Itabela, BA, in replanting areas during pre-planting application of herbicide. Aerial images obtained by a UAV were used to evaluate the effectiveness of the herbicide application for sprouts control. After the images were acquired, they were processed to calculate the normalized difference vegetation index (NDVI) and submitted to a supervised classification to quantify the percentage reduction of sprout green matter. The percentage data were submitted to analysis of variance and the means were compared by Tukey test at 5%. The differences, both visual and average percentages were observed only during the evaluation period with no evident effect of the treatments on sprout control. The images provided by the UAV allowed to monitor and identify visually the plots where biomass reduced or increased and to evaluate the effectiveness of chemical control of eucalyptus sprouts, indicating areas where it was nonexistent, partial or total. 相似文献
86.
C. V. Soares Filho J. F. Cavazzana R. Heinrichs J. M. B. Vendramini G. C. Lima 《Communications in Soil Science and Plant Analysis》2018,49(3):358-370
The management of nitrogen (N) fertilization in pasture has great importance for yield and maintenance of Brazilian livestock. The objective of this study was to evaluate soil chemical attributes, shoot dry weight yield (SDWY) and roots dry weight yield (RDWY), nutritional status and nutritive value of Mulato II Urochloa grass that received organic biofertilizer rates as N source. The treatments were arranged in completely randomized blocks, were fertilized with six organic biofertilizer rates (0, 25, 50, 100, 200, and 400 m3 ha?1) and five replicates during four harvest cycles. There was a quadratic response in the accumulated SDWY for up to a rate of 400 m3 ha?1 and RDWY with 330 m3 ha?1 of organic biofertilizer. The organic biofertilizer influenced the soil chemical attributes and foliar nutrient concentration. However, only the crude protein content presented a quadratic response, and neutral detergent fiber and acid detergent fiber levels were not affected by the influence of organic biofertilizer applied to the soil. 相似文献
87.
Aurivan Soares Freitas Edson Ampélio Pozza Silvino Intra Moreira Maria Gilmara de Oliveira Soares Humberson Rocha Silva Eduardo Alves 《Phytoparasitica》2017,45(3):317-324
Yellow Sigatoka that is caused by Pseudocercospora musae is an important banana disease. The aim of this study was to elucidate the infection process of P. musae in banana leaves by scanning electron microscopy. Leaf samples were inoculated on the abaxial surface with P. musae and then analysed at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h post inoculation (hpi) and at 36 and 50 days post inoculation (dpi). The conidia were found to be germinated between 24 and 36 hpi and penetrated through the stomata between 96 and 120 hpi, or more generally from 144 hpi. P. musae colonized the spongy parenchyma at 36 dpi and the palisade parenchyma at 50 dpi. Sporulation occurred at 50 dpi on the adaxial surface of leaves through the emergence of conidia on conidiophores through the stomata. Considering the importance of yellow Sigatoka in banana production, our results provide a better understanding of the life cycle of the fungus for treatment processes. 相似文献
88.
Allan J. Williamson Joao H.N. Soares Noah D. Pavlisko Robert McAlister Council-Troche Natalia Henao-Guerrero 《Veterinary anaesthesia and analgesia》2017,44(4):738-745
Objective
To characterize the isoflurane-sparing effects of a high and a low dose of fentanyl in dogs, and its effects on mean arterial pressure (MAP) and heart rate (HR).Study design
Prospective, randomized crossover trial.Animals
Eight healthy male Beagle dogs weighing 12.1 ± 1.6 kg [mean ± standard deviation (SD)] and approximate age 1 year.Methods
Dogs were anesthetized using isoflurane and minimum alveolar concentration (MAC) was determined in duplicate by the bracketing method using an electrical stimulus on the tarsus. Animals were administered fentanyl: low dose (33 μg kg?1 loading dose, 0.2 μg kg?1 minute?1) or high dose (102 μg kg?1 loading dose, 0.8 μg kg?1 minute?1) and MAC was re-determined (MACISO-F). Blood was collected for analysis of plasma fentanyl concentrations before administration and after MACISO-F determination. All values are presented as mean ± SD.Results
Isoflurane MAC (MACISO) was 1.30 ± 0.23% in the low dose treatment, which significantly decreased to 0.75 ± 0.22% (average MAC reduction 42.3 ± 9.4%). MACISO was 1.30 ± 0.18% in the high dose treatment, which significantly decreased to 0.30 ± 0.11% (average MAC reduction 76.9 ± 7.4%). Mean fentanyl plasma concentrations were 6.2 and 29.5 ng mL?1 for low and high dose treatments, respectively. MAP increased significantly only in the high dose treatment (from 81 ± 8 to 92 ± 9 mmHg). HR decreased significantly in both treatments from 108 ± 25 to 61 ± 14 beats minute?1 with the low dose and from 95 ± 14 to 42 ± 4 beats minute?1 with the high dose.Conclusions and clinical relevance
Fentanyl administration resulted in a dose-dependent isoflurane MAC-sparing effect with bradycardia at both doses and an increase in MAP only at high dose. Further evaluation is needed to determine the effects of fentanyl on the overall cardiovascular function. 相似文献89.
90.
Cláudio Eduardo Silva Freitas Eduardo Robson Duarte Dorismar David Alves Isabel Martinele Marta D’Agosto Franciane Cedrola Angélica Alves de Moura Freitas Franklin Delano dos Santos Soares Makenzi Beltran 《Tropical animal health and production》2017,49(4):807-812
A ciliate protozoa suppression can reduce methane production increasing the energy efficiency utilization by ruminants. The physicochemical characteristics of rumen fluid and the profile of the rumen protozoa populations were evaluated for sheep fed banana leaf hay in replacement of the Cynodon dactylon cv. vaqueiro hay. A total of 30 male sheep were raised in intensive system during 15 days of adaptation and 63 days of experimental period. The animals were distributed in a completely randomized design that included six replicates of five treatments with replacement levels (0, 25, 50, 75, and 100%) of the grass vaquero for the banana leaf hay. Samples of fluid were collected directly from the rumen with sterile catheters. Color, odor, viscosity, and the methylene blue reduction potential (MBRP) were evaluated and pH estimated using a digital potentiometer. After decimal dilutions, counts of genus protozoa were performed in Sedgewick Rafter chambers. The averages of pH, MBRP, color, odor, and viscosity were not influenced by the inclusion of the banana leaf hay. However, the total number of protozoa and Entodinium spp. population significantly decreased at 75 and 100% inclusions of banana leaf hay as roughage. 相似文献