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排序方式: 共有389条查询结果,搜索用时 62 毫秒
101.
102.
A tumor located in the optic nerve extended through the optic chiasm, involving the hypophysis and the hypothalamic area in a 3.5-year-old male Boxer dog. It showed a biphasic pattern in which numerous highly fibrillated, well-differentiated pilocytic areas were intermingled with pleomorphic, microcystic tumor tissue. Immunohistochemical analysis of the tumor revealed that most of the neoplastic cells were immunoreactive for S-100 protein, with less intensity for glial fibrillary acidic protein (GFAP) and vimentin. A diagnosis of anaplastic astrocytoma was made on the basis of the histopathologic findings and immunohistochemical results. Moreover, there were similarities with the malignant variant of pilocytic astrocytoma described in human adults as an optic chiasmatic-hypothalamic glioma. 相似文献
103.
Phaeomoniella chlamydospora (Pch) and Togninia minima (Tmi) produced scytalone, isosclerone and pullulans in liquid cultures, as well as in calli. Secondary metabolites and host defense compounds were shown to occur in calli of Vitis vinifera cv. Italia and cv. Matilde infected by the esca-associated fungi Pch, Tmi and Fomitiporia mediterranea (Fme). Calli of both cvs. were grown as dual cultures with Pch, Tmi and Fme. The fungi grew well in the presence of calli of both cvs., but callus growth was reduced. Accumulation and changes of total phenolics and recurring phenolics, and of two phytotoxic pentaketides and pullulans were analyzed by HPLC. On comparing results for cv. Italia and cv. Matilde, it can be seen that concentrations of phenolics are strongly related to the cv. The paper discusses the possible relationship between melanin biosynthesis in Pch and Tmi, which utilize pentaketide metabolites as intermediates and their pathogenicity related to phytotoxity of scytalone and isosclerone. 相似文献
104.
Meningioangiomatosis in a dog: magnetic resonance imaging and neuropathological studies 总被引:1,自引:0,他引:1
A case of a dog with a long-standing history of seizures is reported. Neurological examination suggested an intracranial focal lesion, while magnetic resonance imaging disclosed a right cerebral mass with ventricular involvement. Pathological analysis of the resected specimen revealed characteristics of meningioangiomatosis. 相似文献
105.
Daniel Pinto Lucas Pellegrin Lilian Fiori Nitz Sílvio Teixeira da Costa Jos Maria Monserrat Luciano Garcia 《Aquaculture Research》2019,50(10):3017-3027
In this study, the influence of temperature variation on the blood and oxidative stress parameters of pacu Piaractus mesopotamicus juveniles was evaluated. Fish were subjected to gradual changes of temperature, over 5 days, by 24°C until reaching to experimental temperatures 18, 21, 24 (control), 27 and 30°C. There were significant differences (p < .05) in glucose and lactate of blood in both the haematological relationships and oxidative stress parameters. Glucose levels increased at 30°C and decreased at 21°C. Lactate levels were highest at 18°C. While the haematocrit was higher at all altered temperatures, haemoglobin levels decreased at 21°C and increased at 30°C, causing alterations in haematimetric indices. In the liver, glutathione‐S‐transferase (GST) activity was reduced at 18°C while antioxidant capacity against peroxyl radicals (ACAP) was highest at 30°C. Thiobarbituric acid reactive substances (TBARS) increased at 18, 21 and 27°C. In the muscle, ACAP decreased at 27 and 30°C and TBARS increased at 30°C. The results indicate that the species shows sensitivity to temperature variations. Accordingly, we conclude that with short‐term temperature variations >3°C, it is possible to induce higher alterations in the observed parameters in pacu juveniles. 相似文献
106.
Claude E. Boyd Louis R. D'Abramo Brent D. Glencross David C. Huyben Lorenzo M. Juarez George S. Lockwood Aaron A. McNevin Albert G. J. Tacon Fabrice Teletchea Joseph R. Tomasso Jr Craig S. Tucker Wagner C. Valenti 《Journal of the World Aquaculture Society》2020,51(3):578-633
Important operational changes that have gradually been assimilated and new approaches that are developing as part of the movement toward sustainable intensive aquaculture production systems are presented via historical, current, and future perspectives. Improved environmental and economic sustainability based on increased efficiency of production continues to be realized. As a result, aquaculture continues to reduce its carbon footprint through reduced greenhouse gas emissions. Reduced use of freshwater and land resources per unit of production, improved feed management practices as well as increased knowledge of nutrient requirements, effective feed ingredients and additives, domestication of species, and new farming practices are now being applied or evaluated. Successful expansion into culture of marine species, both off and on shore, offers the potential of substantial increases in sustainable intensive aquaculture production combined with integrative efforts to increase efficiency will principally contribute to satisfying the increasing global demand for protein and food security needs. 相似文献
107.
Ali Serhan Tarkan Baran Yourtuolu Fitnat Güler Ekmeki Stacey A. Clarke Louisa E. Wood Lorenzo Vilizzi Gordon Copp 《Fisheries Management and Ecology》2020,27(2):123-131
The European Non‐native Species in Aquaculture Risk Analysis Scheme (ENSARS) was used to assess one of the most popular aquaculture species in the world, the striped catfish Pangasianodon hypophthalmus (Sauvage, 1878), in two locations of southern Anatolia (Turkey). The overall mean risk score generated for P. hypophthalmus by the ENSARS Organism module (which assesses the risks of introduction, establishment, dispersal and impact) indicated that the species poses a medium risk under current climatic conditions. All other ENSARS modules rendered scores that indicated a moderately low risk under current climatic conditions. However, the risks of introducing novel diseases and the actual use (e.g. deliberate introduction to the natural habitats or food market) of the species both attracted scores indicating a medium risk. Confidence levels were medium or high for all modules except the Socio‐economic, with low confidence values also attributed to the risks for farming process of the organism, and its overall risk of spread into the wild during farming procedures and to marketing impacts. Recommendations are provided for further use of the ENSARS scheme, especially for a a priori assessment of potential aquaculture species in Turkey, where the sector has been remarkably developing in the last decades. 相似文献
108.
Grecica Mariana Colombo Cleber dos Santos Simio Marcos Josu Schmitz Virgínia Fonseca Pedrosa Luis Alberto Romano Marcelo Borges Tesser Patrícia Baptista Ramos Wilson Wasielesky Jos María Monserrat 《Aquaculture Research》2020,51(4):1551-1566
This study investigated the effects of the use of the inclusion of açaí on the diet of shrimp Litopenaeus vannamei on antioxidant and histopathological responses after exposure to ammonia. The shrimps were fed two experimental diets: control and with 10% of açaí inclusion (W/W), for 35 days. Afterwards, the organisms were exposed at four concentrations of ammonia (0.01‐control; 0.26; 0.48 and 0.91 mg NH3‐N L?1) for 96 hr. The total antioxidant capacity (ACAP) of the gills decreased significantly in both diets when exposed to ammonia, whereas in the muscle, the açaí promoted an increase in ACAP. Concomitantly, lipid peroxidation levels increased in the gills and decreased in muscle. After exposure to ammonia, glutathione‐S‐transferase activity increased in hepatopancreas in shrimps fed with açaí facilitating the detoxification of lipid peroxidation by‐products, and the concentration of protein sulfhydryl groups decreased in the gills and muscle of the shrimp of the control diet, evidencing protein damage, an unobserved response in shrimps that received the açaí diet. Histopathological changes decreased in açaí‐fed shrimps about the control diet after exposure to ammonia. It is concluded that açaí mitigated ammonia‐induced histopathological changes, improved the antioxidant defence system (gills and muscle) and attenuated the lipid damage in the muscle. 相似文献
109.
Matheus D. Baldissera Carine F. Souza Keiti O. Alessio Katiane W. Krawczak Lorenzo B. Abbad Aleksandro S. da Silva Csar Bizzi Aline F. Ourique Carla C. Zeppenfeld Bernardo Baldisserotto Mauro A. Cunha 《Aquaculture Research》2020,51(10):4196-4205
The aim of this study was to determine whether feed supplementation with nanoencapsulated Ph2Se2 would improve the growth performance of silver catfish and would maintain or improve the muscle antioxidant system. Final mean weight (p = .031), weight gain (p = .014) and specific growth rates (p = .045) were significantly higher in supplemented fish than in the control group. Muscle reactive oxygen species (p = .0001) levels were significantly lower in supplemented fish than in the control group. Also, muscle hydrogen peroxide (p = .0001) and lipid peroxidation (p = .0001) levels were significantly lower in supplemented fish than in the control group. Muscle antioxidant capacity against peroxyl radical (p = .00001) levels were significantly higher in fish supplemented with both Ph2Se2 forms (free or nanocapsules) than in the control group, while muscle superoxide dismutase (p = .001) and catalase (p = .0001) activities were significantly higher in supplemented fish than in the control group. Finally, selenium (Se) deposition (p = .00001) was significantly higher in the muscle of fish supplemented with free and nanoencapsulated forms compared with the control; and deposition levels were significantly higher in fish supplemented with Ph2Se2‐loaded in nanocapsules compared with the free form. Based on this evidence, Ph2Se2‐loaded in nanocapsules improves silver catfish performance and antioxidant/oxidant status. The greater content of Se (1.22 µg/g muscle) in the muscle of fish fed with dietary Ph2Se2‐loaded nanocapsules indicates that it may be considered a nutraceutical for fish. 相似文献
110.
Diogo S. M. Samia Eduardo Bessa Daniel T. Blumstein Jos A. C. C. Nunes Ernesto Azzurro Lorenzo Morroni Valerio Sbragaglia Fraser A. Januchowski‐Hartley Benjamin Geffroy 《Fish and Fisheries》2019,20(5):817-829
In an increasingly anthropic world, humans have profound impacts on the distribution and behaviour of marine fishes. The increased human presence has modified fishes’ antipredator behavioural responses, and consequently flight decisions, as a function of their changed perceptions of risk. Understanding how fish react to human presence can help identify the most vulnerable functional groups/species and estimate impacts caused by human disturbance. Shoal and body size are known to influence fish flight initiation distance (FID; the distance between the predator and prey when the prey begins to escape); however, few studies attempt to test the moderators of these relationships. Here, we present a comprehensive meta‐analysis evaluating FID of fish in response to human presence. Specifically, we investigated six candidate moderators that could influence the relationship between FID with shoal and body size. Our results showed that individual fish size was strongly and positively correlated with FID and the most important moderator that explained the variance in individual body size‐FID relationship was shoaling behaviour. However, and somehow surprisingly, we detected no significant relationship between shoal size and FID. We discuss how these results can inform the development of fish conservation strategies and ultimately assist in the management of marine protected areas. 相似文献