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81.
Carbohydrate metabolism as related to high-temperature conditioning and peel disorders occurring during storage of citrus fruit 总被引:1,自引:0,他引:1
The aim of this research was to understand the involvement of the carbohydrate metabolism in physiological disorders occurring during the postharvest storage of citrus fruit. These disorders, manifested in the rind, depreciate fruit quality and often originate important losses. There has been increasing interest in the use of nonharmful treatments, such as high-temperature conditioning, to avoid citrus peel damage during fruit storage at low temperature in chilling-sensitive cultivars, but their influence in postharvest disorders occurring at nonchilling temperatures and the mechanisms related to them are poorly understood. The data obtained showed that heat conditioning (3 days/37 degrees C) increases the chilling tolerance of cv. Navelate fruit and favored sucrose, but not hexoses, accumulation and its maintenance after the fruit was transferred to low temperature. This effect was related to heat-induced increase in the activities of the sucrose-synthesizing enzymes sucrose phosphate synthase (SPS) and sucrose synthase (SS). Furthermore, sucrose levels and the activities of both enzymes were higher in cv. Pinalate oranges, a chilling-tolerant spontaneous abscisic acid deficient mutant of Navelate. In contrast, carbohydrates appeared not to be involved in the susceptibility of oranges to rind staining, a physiological disorder different from chilling injury, which mainly occurred at a nonchilling temperature (12 degrees C) and was not reduced by heat conditioning. The effect of low temperature in SS and SPS activities was less than that of high temperature, which might be related to the lower changes occurring in sucrose during fruit storage at 2 degrees C. 相似文献
82.
Elisa Carla Barra Freire Lityane Gabriela da Silva Moreira Elane Guerreiro Giese rika Branco Leila Menezes da Silva Ana Rita de Lima 《Anatomia, histologia, embryologia》2019,48(5):421-428
The ocelot (Leopardus pardalis) is a Felidae of wide geographical distribution and food flexibility; therefore, it is essential to understand the morphology of the species. Thus, we aimed to describe its lingual morphology in order to gain information regarding the anatomy of this carnivore's digestive system. The tongues ??were removed for ex situ macroscopic and morphometric analyses, as well as for light microscopy and scanning electron microscopy, of fragments of the different lingual regions. The tongue of L. pardalis had an elongated form that was subdivided into the apex, body and root, in which four papillary types were observed: filiform, fungiform, circumvallate and conical. It presented with a stratified, keratinized squamous epithelium, followed by loose and dense connective tissues, as well as a skeletal striated musculature that comprised most of the organ. In addition, in scanning electron microscopy the filiform papillae showed a complex with multiple layers of keratin with triangular shape projected caudally in oral cavity. The fungiform papillae were distributed among the filiform and showed a rounded shape with some gustatory pores, and are keratinized but in a lower intensity if compared with filiform. The vallate papillae, located in lingual root, showed an oval format, had a deep groove surrounded the papillae and some gustatory pores. The conical papillae are located in lingual root and are similar to the filiform. The tongue of L. pardalis resembles other carnivorous species, mainly among felids. However, it differed in relation to the quantity of vallate papillae and the absence of foliate papillae. 相似文献
83.
Ostriches are susceptible to a wide variety of diseases that can affect their commercial breeding. The aim of this study was to identify morphologically Codiostomum struthionis and examine its seasonal occurrence among animals of three age categories in two commercial farms in Areal and Itaboraí, State of Rio de Janeiro, Brazil. Fresh fecal samples were collected monthly, from June 2004 to May 2006. Eggs per gram of feces (EPG) were counted after centrifugal flotation in saturated sugar solutions and infective larvae were evaluated after coproculture. A total of 432 fecal samples were collected from three groups according to ostrich age: up to 90 days, 91-365 days and over 365 days (adults). The dry and rainy seasons were defined according to official meteorological data. Typical eggs of the Strongylida order were identified in 242 samples (235 from adult ostriches). Once obtained, infective larvae were identified as C. struthionis. Adult ostriches exhibited significantly greater numbers of eggs in their feces during the rainy season compared to the dry season (p<0.05). In the Areal farm, significant (p<0.05) values were found when adults ostriches EPG were compared to ostriches up to 90 days and also for ostriches from 91 to 365 days. When comparing adult EPGs between the two commercial breeding farms, Areal exhibited greater EPGs during both the dry (p=0.0215) and rainy (p=0.0011) seasons. 相似文献
84.
Genetic differentiation and historical demography of wood stork populations in Brazilian wetlands: Implications for the conservation of the species and associated ecosystems 下载免费PDF全文
Carolina I. Miño Luiza H. da Silva Avelar Fagner M. da Silva Manolo F. Perez Luiza F. Menezes Silvia N. Del Lama 《水产资源保护:海洋与淡水生态系统》2017,27(6):1313-1324
85.
Reproductive System of Brown‐throated Sloth (Bradypus variegatus,Schinz 1825, Pilosa,Xenarthra): Anatomy and Histology 下载免费PDF全文
S. M. Favoretto E. G. daSilva J. Menezes R. R. Guerra D. B. Campos 《Anatomia, histologia, embryologia》2016,45(4):249-259
In recent years, habitat degradation led to the decline of some populations of brown‐throated sloth. The aim of this study was to describe morphological features of the female reproductive system of the species. The oval ovaries were partially surrounded by ovarian bursa. An external cortex and an inner medulla were present. Corpora lutea and corpora albicans together with follicles at various stages of development each with a single oocyte were found in the cortex. Uterine tubes were tortuous, tubular, travelled around the perimeter of the ovary and possessed a folded mucosa with ciliated pseudostratified epithelium. Uterus was simplex, with no horns and divided into three parts: a pear‐shaped cranial segment and a long caudal uterine segment (both forming the body of the uterus) and two cervices. Uterus presented three layers: mucosa, lined by pseudostratified epithelium, muscular and serosa. The cervices connected the uterus to the urogenital sinus, a distensible cavity with longitudinal mucosal folds lined by transitional epithelium that extended from the external urethral orifice and the external uterine ostia to the vulva, which was lined by a keratinized stratified squamous epithelium. Brown‐throated sloth presented a bipartite clitoris with paired crura, bodies and glandes. The presence of a double cervix and a bipartite clitoris was unique features of the species. 相似文献
86.
Salomé Menezes Amadeu M. V. M. Soares Lúcia Guilhermino Mika R. Peck 《Water, air, and soil pollution》2010,208(1-4):317-322
This work aimed to determine the sensitivity of acetylcholinesterase (AChE) and glutathione S-transferases (GST) activities of Crangon crangon (L.) to the water-accommodated fraction (WAF) of the fuel oil spilled by the oil tanker Prestige, in order to assess their usefulness as markers for this kind of pollution. Laboratory exposure of shrimps to WAF of weathered Prestige fuel oil showed no significant interference with AChE activity. Significant induction of GST activity was observed, potentially as a result of high concentrations of polycyclic aromatic hydrocarbons. However, these results were only obtained with the higher WAF concentrations tested. It was concluded that AChE and GST activities of C. crangon were not useful biomarkers for short-term exposure to the WAF of fuel oil spilled by the tanker Prestige and carried to the beaches of Galicia (NW Spain). 相似文献
87.
Ribeiro MN Bruno-de-Sousa C Martinez-Martinez A Ginja C Menezes MP Pimenta-Filho EC Delgado JV Gama LT 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2012,129(1):79-87
Brazilian goat breeds are believed to derive mainly from animals brought by Portuguese settlers since the 16th century. We used microsatellite markers in a sample of 436 animals to study genetic variability and differentiation of the six Portuguese (PT) and six Brazilian (BR) goat breeds currently recognized in the two countries. These breeds were also compared with an outgroup represented by a sample of Alpine (ALP) goats. The effective number of alleles and allelic richness were slightly higher in PT than in BR breeds. The global F(ST) was nearly 0.11 when PT and BR breeds were considered, with a mean pairwise F(ST) of about 0.03 among PT breeds, 0.07 among BR breeds and 0.15 between PT and BR breeds. The dendrogram illustrating relationships between populations and the correspondence analysis indicate the existence of two very distinct clusters, corresponding to the countries of origin of the breeds studied, which are nearly equidistant from the Alpine outgroup. The analysis with structure confirmed the separation between PT and BR breeds but suggests that some BR breeds, especially Graúna and Canindé, may share a common ancestry with PT breeds. The divergence observed between PT and BR breeds may result from founder effects and genetic drift but could also reflect the introduction in Brazil of goats originating from other regions, e.g., West Africa. 相似文献
88.
Wanderley Alysson Martins Ítavo Luís Carlos Vinhas dos Santos Geraldo Tadeu Ítavo Camila Celeste Brandão Ferreira Cunha Camila Soares dos Santos Difante Gelson Dias Alexandre Menezes Mateus Rodrigo Gonçalves de Oliveira Marcus Vinícius Moraes 《Tropical animal health and production》2021,53(5):1-11
Tropical Animal Health and Production - The emergence of tick-borne diseases has been reported as a serious problem in public health worldwide and many aspects of its epidemiology and effects on... 相似文献
89.
Monção Flávio Pinto Santana Pedro Felipe Júnior Vicente Ribeiro Rocha Ruas José Reinaldo Mendes Rigueira João Paulo Sampaio Borges Lucas Daniel Alcântara de Castro Menezes Gustavo Chamon Sousa Thais Eleonora Santos da Costa Maria Dulcinéia Oliveira Laura Lúcia Santos de Queiroz Fausto Expedito 《Tropical animal health and production》2020,52(1):141-149
Tropical Animal Health and Production - The quantitative feed restriction of lactating cows has been used in intensive production systems as a strategy to reduce production costs. However, the... 相似文献