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961.
Summary Nuclear rods and sheets are described in neurons from the cerebellar cortex of rats alcoholized through ingestion of a 20 % aqueous ethanol solution over a period of 90 and 180 days. An eventual relationship between these nuclear inclusions and alcoholization is advanced. 相似文献
962.
963.
Come to the dark side: habitat selection of larval odonates depends on background visual patterns
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Rafael I. S. Tavares Gabrielle C. Pestana Alana D. Rocha Daniele C. Schiavone Rhainer Guillermo‐Ferreira 《Ecological Entomology》2018,43(5):640-646
1. Determining which environmental traits enable animals to inhabit and choose preferred habitats is key to understanding ecological processes. Habitat complexity and background colour patterns can act as selective pressures on animal behaviour, and ultimately affect habitat choice. 2. To investigate the role of environmental features on habitat selection, this study looked at whether dragonfly and damselfly larvae show a preference between dark/light or complex environments. Last‐instar larvae of Micrathyria didyma (Odonata: Libellulidae) and Acanthagrion lancea (Odonata: Coenagrionidae) were collected in the Neotropical savanna, and five experiments in laboratory conditions were subsequently carried out. The first experiment tested the preference of larvae for leaves in contrast to a white background. The second experiment compared a preference for white and black backgrounds. As both experiments showed a significant preference for darker backgrounds, a predator was included in the black background in the third experiment, and a macrophyte was included in the white background in the fourth experiment. In this way, favourable and unfavourable conditions were included in the habitat of choice. The fifth experiment tested the influence of environmental complexity on habitat choice. 3. The results of these experiments showed that larvae choose darker backgrounds independently of predation risk, and that macrophytes are as attractive as a dark background. They also suggest that the coenagrionid, but not the libellulid, prefer more complex environments. 4. Overall, these findings suggest that larvae exhibit behavioural preferences for background colour and complexity, which may ultimately drive habitat occupation. 相似文献
964.
Reassessment of the evolutionary relationships within the dog‐faced bats,genus Cynomops (Chiroptera: Molossidae)
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Ligiane M. Moras Valéria da C. Tavares Almir R. Pepato Fabrício R. Santos Renato Gregorin 《Zoologica scripta》2016,45(5):465-480
The low representativeness of the dog‐faced bats (genus Cynomops Thomas, 1920 ) in collections has constrained the study of the diversity and the evolutionary relationships within this genus. Taxonomic revisions of some taxa, in particular the large‐sized Cynomops abrasus (Temminck, 1827 ), are crucial for understanding the phylogeny of Cynomops. A total of four subspecies of C. abrasus have been described to date, all widespread in South America: C. a. mastivus (Thomas, 1911 ), C. a. brachymeles (Peters, 1865), C. a. cerastes (Thomas, 1901 ) and C. a. abrasus (Temminck, 1827 ). Here, we evaluated the phylogenetic relationships within Cynomops, and the status of the four C. abrasus subspecies using complete sequences of two mitochondrial genes (Cyt b and COI) and 39 morphological characters. Maximum‐parsimony, maximum‐likelihood and Bayesian phylogenetic reconstructions recovered a novel hypothesis for Cynomops, supported the recognition of C. a. mastivus as a distinct species, separated from C. abrasus, and two hypotheses of lineages previously unrecognized for Cynomops. The use of mitochondrial genes combined with morphological characters revealed again to be a powerful tool to recover the phylogenetic relationships within Cynomops and demonstrated that the genus is more diverse than previously thought. 相似文献
965.
Márcio Tavares Sofia Ramalheira Sérgio Chacim Rui Henrique Ângelo Oliveira José Mário Mariz 《Reports of Practical Oncology and Radiotherapy》2019,24(4):344-346
Chylous ascites is an extremely rare complication of lymphoma. Here, we discuss the case of a patient presenting with refractory chylous ascites due to a massive retroperitoneal follicular lymphoma, staged as IVB. The patient was unresponsive to chemoimmunotherapy, which prompted us to consider alternative treatment strategies. Low-dose radiotherapy was initiated and resulted in a marked decrease of the lymphadenopathy and complete regression of the peritoneal fluid. Low-dose radiotherapy represents a well-tolerated, highly effective treatment and should remain an important modality in cases of follicular lymphoma-associated chylous ascites. 相似文献
966.
Karina H. M. Cardozo Marcone A. L. Oliveira Marina F. M. Tavares Pio Colepicolo Ernani Pinto 《Biological Rhythm Research》2002,33(4):371-382
The levels of the fatty acids, cis eicosahexenoic acid and cis linolenic acid, as well as the extent of lipoperoxidation, measured as malondialdehyde (MDA), were analyzed in the photosynthetic marine dinoflagellate Lingulodinium polyedrum at different times during the light : dark (L : D) cycle. Levels of MDA were twice as high during the day phase than during the night phase. This may be related to the circadian rhythm in photosynthesis as during photosynthetic electron flux, electrons can 'leak' and react with molecular oxygen producing reactive oxygen species (ROS) which in turn react with lipids, proteins, and DNA among other biomolecules. Fatty acid levels were highest during the day phase. Our findings indicate that unsaturated fatty acids are more susceptible to attack and degradation when L. polyedrum is exposed to light and that the cells compensate for this by an increased fatty acid content during the day. Excessive lipoperoxidation during the light phase could result in a higher level of chloroplast or plasma membrane disruption leading to cell death. 相似文献
967.
Andreia Machado da Silva Ana P.M. Tavares Cristina M.R. Rocha Raquel O. Cristóvão José A. Teixeira Eugénia A. Macedo 《Process Biochemistry》2012,47(7):1095-1101
The aim of this work was to assess the possibility of using beer spent grain (a byproduct of beer's brewing industry) as a carrier for laccase immobilization. Both adsorption (on spent grain – SG and on digested spent grain – DSG) and covalent binding (using glycidol and glycidol followed by ethylenediamine on DSG) were used. The effect of different immobilization conditions on the immobilization yields and recovered activities such as contact time, enzyme concentration and pH was evaluated. For the best conditions, immobilization yields, recovered activities and thermal, operational and storage stabilities were also evaluated. Finally, the Michaelis–Menten mechanism was applied and the parameter with respect to ABTS oxidation was determined.Enzyme immobilization on DSG led to the best enzyme activities (recovered activities as high as 90%) and to high storage and operational stabilities (10 cycles). Thermal stability was also improved and the half-life of immobilized laccase in SG increased from 0.64 h to 1.1 h at 70 °C. 相似文献
968.
969.
Leite Cristiana Torres Ferreira Darley Aparecido Tavares Vieira Ariane Tonetto Praça-Fontes Milene Miranda Ferreira Adésio Carvalho Carlos Roberto Clarindo Wellington Ronildo 《Plant Cell, Tissue and Organ Culture》2019,136(3):549-560
Plant Cell, Tissue and Organ Culture (PCTOC) - Tissue culture in Passiflora has emerged as a strategy to propagate species with agronomic relevance, which is the main focus of most in vitro... 相似文献
970.
C M Pacheco C A Tavares P M Coelho O A Rocha J M Santos F R Prado J N Francischi 《Mediators of inflammation》1998,7(4):261-267
THIS study intended to characterize pharmacologically the mediator(s) released in the inflammation induced by Soluble Egg Antigen (SEA), the main antigen released from eggs of Schistosoma mansoni, in rat hindpaws. A single intraplantar injection of 0.1-100 microg SEA at day zero induced a dose-dependent increase in the volume of rat hindpaws characterizing an oedema of quick onset (within 15 min) and 4h-duration, which was confirmed by histopathological analysis of the paws. A second injection of SEA in the same paw (1-10 microg) 28 days later induced an increased dose-dependent oedematogenic response. The early oedematogenic response following SEA sensitization was derived from serotonin release and interleukin-1 (IL-1), since treatment with either pizotifen or an antibody against IL-1, reduced the response by 60% and 48%, respectively. The increased oedematogenic response derived from SEA-challenge (10 microg) of rat paws derived from a local rather than systemic reaction, since it was not observed if the sensitization was in the contralateral paw or the peritoneal cavity of the animals. Chronic treatment with inhibitors of IL-2 synthesis/release such as cyclosporin or dexamethasone during the sensitization phase reduced the oedematogenic response due to SEA challenge by 51% and 55%, respectively. These data suggested that SEA-challenge was immune-derived and dependent of IL-2 release. It is discussed the association between cytokine release and the resistance of rats to S. mansoni infection. 相似文献