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361.
Christopher T. Ryan Eric N. Glass Gabriela Seiler Allison L. Zwingenberger Wilfried Mai 《Veterinary radiology & ultrasound》2014,55(3):292-299
Multiple congenital or developmental anomalies associated with the central nervous system have been reported in English Bulldogs. The purpose of this retrospective study was to identify and describe the prevalence and MRI characteristics of these anomalies and their association with presence and degree of cerebral ventriculomegaly. Magnetic resonance imaging studies of 50 English Bulldogs were evaluated. Forty‐eight dogs had some degree of cerebral ventriculomegaly, 27 of which had an otherwise normal brain. Presence of lateral ventriculomegaly was not significantly associated with presence of another intracranial lesion. Appearance of the septum pellucidum was variable, ranging from intact to incomplete or completely absent. The corpus callosum was subjectively thinned in all but three dogs, two of which had normal lateral ventricles. Fusion of the rostral colliculi was not found in any dog. A persistent craniopharyngeal canal was identified in one dog. Aqueductal stenosis caused by fusion of the rostral colliculi was not identified in any dog. Findings indicated that cerebral ventriculomegaly is a common finding in English Bulldogs with or without other intracranial lesions, aqueductal stenosis caused by fusion of the rostral colliculi is unlikely to be a common etiology leading to obstructive hydrocephalus, and a large craniopharyngeal canal is a rare finding that has unknown clinical significance at this time. 相似文献
362.
Nelly Tremblay Marcelo García-Guerrero Fernando Díaz Claudia Caamal-Monsreal Gabriela Rodríguez-Fuentes Kurt Paschke Paulina Gebauer Carlos Rosas 《Aquaculture Research》2022,53(1):63-74
The present study was designed to assess the performance of the freshwater prawn Macrobrachium tenellum in optimal and sub-optimal dissolved oxygen conditions, considering increasing environmental pressures. Thermal tolerance and thermal metabolic scope (TMS) with related integrated biomarker response (IBR) were measured in prawns exposed to normoxia (80% air saturation), mild (40% air saturation) and severe hypoxia (25% air saturation) at three exposure time points (10, 20 and 30 days). Effects of hypoxia on thermal tolerance were not detectable over time; they were perhaps masked by hyperventilation, or by an increase or diversion of haemolymph processes. After 30 days, TMS was 11% higher in mild hypoxia compared with normoxia, while it was 64% lower in severe hypoxia, indicating the loss of aerobic metabolism capacity during the latter. Mild-hypoxia prawns maintained a high IBR over time, supported by antioxidant enzyme activities (mainly superoxide dismutase), which helped avoid the serious oxidative damage (proteins and lipids) seen in severe hypoxia animals, as well as lower acetylcholinesterase activity that indicated failure of communication between the nervous and locomotor systems. Our results documented a high tolerance by M. tenellum to mild-hypoxia events, which should be further tested under seasonal and extreme habitat/tank temperatures. 相似文献
363.
Laura Prosdocimi Natalia S. Teryda Gabriela S. Navarro Raymond R. Carthy 《水产资源保护:海洋与淡水生态系统》2021,31(4):830-840
- Fisheries bycatch of non-target species in the commercial fleet is a major source of anthropogenic injury and mortality for sea turtles and marine megafauna.
- The Río de la Plata maritime front (RLPMF) and its adjacent international waters – comprising part of the Argentine and Uruguayan exclusive economic zones, is a highly important fishing ground in the south-western Atlantic Ocean as well as feeding and development grounds for sea turtles.
- This paper analyses the distribution of the bottom and pelagic trawling fishery within the RLPMF using information from Vessel Satellite Monitoring System. With this information, areas of highest trawling intensity were defined and further evaluated their overlap with sea turtle habitat-use areas from available sea turtle satellite tracking information.
- Results besides identifying high-susceptibility areas for sea turtle bycatch by the commercial trawler fleet along the RLPMF, provide predictive tools to identify vulnerable areas to interaction of sea turtles and the commercial fishing fleet.
- Implementation of bycatch mitigation measures, such as reduced fishing effort areas by the Argentine and Uruguayan fisheries management agencies has the potential to benefit the fisheries as well as marine megafauna. Furthermore, there is a need for additional research on the impact that this fleet can have on sea turtles present in the area.
364.
Monika Krzewska Ilona Czyczyło-Mysza Ewa Dubas Gabriela Gołębiowska-Pikania Iwona Żur 《Euphytica》2015,206(1):263-278
365.
Gabriela S. BLANCO Stephen J. MORREALE Jeffrey A. SEMINOFF Frank V. PALADINO Rotney PIEDRA James R. SPOTILA 《Integrative zoology》2013,8(3):293-306
Using satellite transmitters, we determined the internesting movements, spatial ecology and diving behavior of East Pacific green turtles (Chelonia mydas) nesting on Nombre de Jesús and Zapotillal beaches along the Pacific coast of northwestern Costa Rica. Kernel density analysis indicated that turtles spent most of their time in a particularly small area in the vicinity of the nesting beaches (50% utilization distribution was an area of 3 km2). Minimum daily distance traveled during a 12 day internesting period was 4.6 ± 3.5 km. Dives were short and primarily occupied the upper 10 m of the water column. Turtles spent most of their time resting at the surface and conducting U‐dives (ranging from 60 to 81% of the total tracking time involved in those activities). Turtles showed a strong diel pattern, U‐dives mainly took place during the day and turtles spent a large amount of time resting at the surface at night. The lack of long‐distance movements demonstrated that this area was heavily utilized by turtles during the nesting season and, therefore, was a crucial location for conservation of this highly endangered green turtle population. The unique behavior of these turtles in resting at the surface at night might make them particularly vulnerable to fishing activities near the nesting beaches. 相似文献
366.
Gabriela Burgos Lupita Muñoa Paola Sosa Merideth Bonierbale Thomas zum Felde Carlos Díaz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):385-390
Yellow fleshed potatoes contain significant amounts of lutein and zeaxanthin but the bioaccessibility of potato carotenoids has not yet been investigated. The purpose of this study was to estimate the in vitro bioaccessibility of carotenoids provided by potato. Lutein and zeaxanthin concentrations of boiled, freeze dried and milled samples of seven yellow fleshed potato accessions were determined by HPLC before and after different steps (gastric, duodenal and micellar phase) of in vitro digestion. The gastric and duodenal digestive stability of lutein and zeaxanthin in boiled tubers of the different accessions ranged from 70 to 95 % while the efficiency of micellarization ranged from 33 to 71 % for lutein and from 51 to 71 % for zeaxanthin. For all accessions, amounts of lutein and zeaxanthin after micellarization were significantly lower than the original amount found in the boiled samples. The accession 701862 showed the highest bioaccessible lutein concentration (280 μg/100 g, FW) and the accessions 703566 and 704218 showed the highest bioaccessible zeaxanthin concentration (above 600 μg/100 g, FW). Considering the mean potato intake in the Andes (500 g per day), the accession 701862 provides 14 % of the lutein intake suggested for health benefits and the accessions 703566 and 704218 provide 50 % more than the suggested zeaxanthin intake. 相似文献
367.
Viviana R. Lucero López Gabriela S. Razzeto Nora L. Escudero M. Sofía Gimenez 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):396-402
Hyperlipidemia and hepatic steatosis are frequent alterations due to alcohol abuse. Amaranth is a pseudocereal with hypolipidemic potential among other nutraceutical actions. Here we study the effect of Amaranthus hypochondriacus (Ah) seeds on serum and liver lipids, and the expression of genes associated to lipid metabolism and liver histology in male Wistar rats intoxicated with ethanol. The animals were divided into four groups; two groups were fed the American Institute of Nutrition 1993 for maintenance diet (AIN-93M), and the other two with AIN-93M containing Ah as protein source. One of each protein group received 20 % ethanol in the drinking water, thus obtaining: CC (control casein), EC (ethanol casein), CAh (control Ah) and EAh (ethanol Ah). When comparing EAh vs. EC, we found a positive effect of Ah on lipids, preventing the increment of serum cholesterol (p?<?0.001), through the higher expression of the LDL receptor (p?<?0.001); and it also decreased free (p?<?0.05) and esterified cholesterol (p?<?0.01) in liver, probably via the reduction of the 3-hydroxy-3-methylglutaryl coenzyme A reductase expression (p?<?0.001). We also observed that amaranth contributed to the decrease of fat deposits in liver, probably through the decrease in acetyl-CoA carboxylase alpha (p?<?0.01), glycerol-3-phosphate acyltransferase 1 (p?<?0.01) and diacylglycerol O-acyltransferase 2 (p?<?0.05) expression. The histological study showed a decrease in the fat deposits in the amaranth group when compared to casein; this is consistent with the biochemical and molecular parameters studied in this work. In conclusion, amaranth could be recommended to avoid the alterations in the lipid metabolism induced by alcohol and other harmful agents. 相似文献
368.
Sybuia Priscila Ayumi de Castro-Prado Gabriela de Carvalho Nunes William Mário Zanutto Carlos Alexandre Kaneshima Edilson Nobuyoshi Soares Dartanhã José da Silva Franco Claudinéia Conationi de Freitas Mathias Paulo Cezar de Castro-Prado Marialba Avezum Alves 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):937-950
European Journal of Plant Pathology - Charcoal rot is an economically important fungal disease of economically important crops. Several species of the Macrophomina genus, such as M.... 相似文献
369.
Mergers play an important role in galaxy evolution and are key to understanding the correlation between central-black hole mass and host-galaxy properties. We used the new technology of adaptive optics at the Keck II telescope to observe NGC 6240, a merger between two disk galaxies. Our high-resolution near-infrared images, combined with radio and x-ray positions, revealed the location and environment of two central supermassive black holes. Each is at the center of a rotating stellar disk, surrounded by a cloud of young star clusters. The brightest of these young clusters lie in the plane of each disk, but surprisingly are seen only on the disks' receding side. 相似文献