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排序方式: 共有209条查询结果,搜索用时 15 毫秒
1.
Hanne Digre Ulf Erikson Ekrem Misimi Inger Beate Standal Lorena Gallart-Jornet Siriporn Riebroy 《Journal Of Aquatic Food Product Technology》2013,22(4):391-411
The main objectives of the study were to (a) assess the effect of perimortem stress on blood drainage, (b) compare the efficiency of gill cutting and direct gutting as bleeding methods, and (c) compare pre- and postrigor filleting strategies for presence of residual blood in Atlantic cod fillets. Anesthetized cod had significantly higher drainage of blood compared to stressed fish. Nevertheless, the visual assessments of residual blood were not affected by stress or bleeding method. Some minor, but significant, differences between pre- and postrigor fillets were found. Stressed fish were initially less light in color than those unstressed, but after ice storage there was no noticeable difference. However, initially, the largest difference in fillet color was due to different bleeding methods. Fillets cut from fish subjected to gill cutting were lighter and less red in color than those bled by direct gutting. After 7 and 21 days of storage, the color differences observed in fresh and salted fillets, respectively, were mainly due to the different rigor status when they were filleted, indicating that fillets cut postrigor were superior to fillets cut prerigor. Prerigor filleting resulted in lower water holding capacity after ice storage in anesthetized, direct gutted cod. 相似文献
2.
Ota Erika do Carmo Cardoso Claudia Andrea Lima Inoue Luis Antonio Kioshi Aoki Zanon Ricardo Basso Silva Tarcila Souza de Castro 《Fish physiology and biochemistry》2022,48(3):735-748
Fish Physiology and Biochemistry - The present study was carried out to evaluate the genotoxic potential of nutritional quality of feed, using erythrocytic nuclear abnormalities assay in Nile... 相似文献
3.
David Fernndez‐Calvio Lorena Prez‐Armada Laura Cutillas‐Barreiro Remigio Paradelo‐Núez Avelino Núez‐Delgado María J. Fernndez‐Sanjurjo Esperanza lvarez‐Rodriguez Manuel Arias‐Estvez 《Land Degradation \u0026amp; Development》2016,27(4):1276-1285
Mining activities are related to relevant environmental pollution issues that should be controlled. We used sequential extractions to fractionate Cd, Cu, Ni, Pb and Zn retained on unamended or mussel shell‐amended mine soil samples, all of them treated with a mixture of the five heavy metals (total metal concentration of 1·57 mmol L−1), after 1, 7 and 30 days of incubation. In addition, we used the stirred flow chamber technique to study the release of each of the five heavy metals from these different unamended and shell‐amended soil samples. The results indicate that the shell amendment caused a decrease in the most soluble fraction, while increasing the most recalcitrant (least mobile) fraction. With equivalent implications, the stirred flow chamber experiments showed that mussel shell amendment was associated to a decrease in heavy metal release and increased retention. The highest mussel shell dose and incubation time caused the most relevant changes in pH values and thus in metal retention, also indicating the importance of pH modifications in the mechanism of retention acting in the amended samples. In view of these results, the use of mussel shell amendment can be encouraged to increase heavy metal retention in acid mine soils, in order to minimise risks of environmental pollution. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
4.
Gelfand MJ Raver JL Nishii L Leslie LM Lun J Lim BC Duan L Almaliach A Ang S Arnadottir J Aycan Z Boehnke K Boski P Cabecinhas R Chan D Chhokar J D'Amato A Ferrer M Fischlmayr IC Fischer R Fülöp M Georgas J Kashima ES Kashima Y Kim K Lempereur A Marquez P Othman R Overlaet B Panagiotopoulou P Peltzer K Perez-Florizno LR Ponomarenko L Realo A Schei V Schmitt M Smith PB Soomro N Szabo E Taveesin N Toyama M Van de Vliert E Vohra N Ward C Yamaguchi S 《Science (New York, N.Y.)》2011,332(6033):1100-1104
With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change. 相似文献
5.
Luis V. García Cristina Ramo Cristina Aponte Adela Moreno María T. Domínguez Lorena Gómez-Aparicio Ramón Redondo Teodoro Marañón 《Biological conservation》2011,(2):764-771
Conservation management conflicts frequently arise when an overpopulation of a protected organism has negative effects on other valuable elements in the same ecosystem. We studied the interactions between a colony of protected tree-nesting wading birds and a remnant population of centenarian cork oaks that was part of the formerly dominant forests in the Doñana Biological Reserve (SW Spain). A significant increase in the tree mortality rates has been recorded in areas that are yearly influenced by the bird colony.We analysed a cohort of surviving trees using a gradient of nesting bird influence. Tree-nesting history, bird isotopic signature (δ15N), tree health-related parameters (defoliation, δ13C and leaf surface coverage by faeces) and several soil variables were evaluated. Bird influence was related to increased soil salinity. This increase correlated to increased water-use efficiency for the leaves and to crown defoliation, suggesting that the heavily occupied trees are under higher stress and in poorer health condition than the unoccupied ones. We tested structural equations models (SEM) that were based on hypothesised bird effects on the health of the trees. Soil-mediated effects of the nesting birds best explained the symptoms of the declining health of the trees, whereas the percent of leaves’ surface that was covered by faeces did not improve the fitted SEM model.For the reserve’s managers, a challenging trade-off exists between preserving the relict trees, which have a high genetic diversity and a key ecological role in these savannah-like ecosystems, and maintaining the current nesting area for these protected, but expanding, wading birds. 相似文献
6.
Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from March 2004 to July 2005, with six mist-nets, during two nights, using the capture-recapture method. We captured 2970 individuals of 43 bat species. Montane rainforest had the greatest alpha diversity (H′ = 2.681; n = 37), whereas alpha diversity was similar among coffee plantations (H′ = 2.229-2.364; n = 23-26). The number of frugivorous and nectarivorous species was similar among the sites; the greatest exchange in species composition (beta diversity) occurred for insectivorous bats, which reduce their number in coffee plantations as pesticides are incorporated. Bat richness species was significantly related to the number of vegetation strata, height, and cover of trees. We suggest that coffee plantations could act as corridors, facilitating connection among different elements of the landscape in the Sierra Madre de Chiapas for some frugivorous and nectarivorous bats. 相似文献
7.
The effect of olive stone removal before processing on the degradation level, secoiridoid and tocopherol contents, and antioxidant activity of monovarietal extra virgin olive oils (EVOOs) was studied. EVOOs were extracted from olives of the Leccino, Moraiolo, Frantoio, Pendolino, Taggiasca, and Colombaia varieties both in the presence and in the absence of the stones. The degradation level of EVOOs was evaluated by acidity, peroxide number, and spectroscopic indices K(232) and K(270), according to EU regulation. The secoiridoid compounds typical of EVOO, namely, the oleuropein and ligstroside derivatives, hydroxytyrosol, tyrosol, and tocopherols were analyzed by HPLC. The antioxidant activity was evaluated by the xanthine oxidase/xanthine system, generating superoxide radical and hydrogen peroxide, and by the 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl test. Results showed that EVOOs obtained from both stoned and destoned olives had a very low degradation level, which was not affected by destoning. Destoning lowered slightly the alpha-tocopherol content in EVOOs but increased the total secoiridoid content and the antioxidant activity of EVOOs (up to 3.5-fold). However, these effects were variety-dependent and negligible in some conditions. It was concluded that a better knowledge of the reactions occurring during olive processing, and particularly on the involvement of endogenous pulp and stone enzymes, is essential to predict the effect of destoning on EVOO quality. 相似文献
8.
Basso W Venturini MC Bacigalupe D Kienast M Unzaga JM Larsen A Machuca M Venturini L 《Veterinary parasitology》2005,131(3-4):299-303
Generalized neosporosis was diagnosed in a 2-month-old boxer puppy. The dog had a history of progressive paralysis and muscle atrophy, followed by cervical weakness, stiff jaws and dysphagia. The dog had a 1:12,800 antibody titer for Neospora caninum and was negative for antibodies to Toxoplasma gondii by the indirect fluorescent antibody test (IFAT). After euthanasia a complete necropsy was carried out. The puppy had a megaesophagus. Microscopically, tachyzoites and tissue cysts were observed in histologic brain sections. Severe myositis was observed in esophagus and striated muscle sections and several groups of tachyzoites were associated with these lesions. Immunohistochemically, parasites in the brain and striated muscle reacted to anti-N. caninum antiserum. Western blot analysis allowed the identification of three major and four minor antigens of N. caninum tachyzoites corresponding to 30, 37, 45-kDa and 28, 29, 43, 47 and 67-kDa bands, respectively. Cerebral homogenate of the dog was inoculated into four Mongolian gerbils (Meriones unguiculatus). Forty-nine days after inoculation, all the gerbils had positive IFAT titers to N. caninum (1:200, 1:400, 1:100 and 1:400). Genomic DNA was isolated from the brain, lung and striated muscle from the puppy and from the brain of one of the inoculated gerbils. The N. caninum specific primer pair Np 6/21 produced 328 bp amplicons on electrophoretic gels. This is the first confirmed clinical case of generalized canine neosporosis in Argentina. 相似文献
9.
Venturini MC Bacigalupe D Venturini L Rambeaud M Basso W Unzaga JM Perfumo CJ 《Veterinary parasitology》2004,124(3-4):161-165
The objective of the present study was to determine the prevalence of Toxoplasma gondii antibodies from slaughter sows and from pigs raised at an indoor and an outdoor swine farm. Serum samples were obtained from 230 slaughter sows belonging to 83 farms distributed in 5 provinces. Blood samples were collected monthly from pigs of different ages from an intensive management indoor farm (farm 1). A cross-sectional study was carried-out from an outdoor farm (farm 2). All sera were tested for T. gondii antibodies by the modified agglutination test (MAT), using formalin-fixed tachyzoites as antigen. An antibody titer > or =1:25 was considered positive. Antibodies to T. gondii were detected in 87 (37.8%) of 230 sows sera. Distribution among provinces was: 37.1% from Santa Fe, 62.8% from Buenos Aires, 3.3% from San Luis, 58.7% from La Pampa and 24% from Córdoba. Four of 88 (4.5%) serum samples from farm 1 had antibodies to T. gondii and none of the negative pigs seroconverted. However, 45 of 112 samples from farm 2 were positive (40.2%) with the following distribution: sows 100%; nursery 40%; growers 13.8% and fatteners 20%. It is concluded that the prevalence of T.gondii antibodies among sows seems to be quite variable. T. gondii prevalence was related to the facilities and management of the farm. 相似文献
10.
The open reading frame of the S3 segment encoding the sigma2 protein of four turkey reovirus field isolates was analyzed for sequence heterogeneity. The turkey reoviruses we present here have a 97% amino acid identity to turkey NC 98. The S3 nucleotide and amino acid sequence similarity was < or =61% and 78%-80%, respectively, when compared to the chicken reovirus isolates. Comparison of amino acid sequences from chickens and turkeys with that of a duck isolate revealed a 53% and 55% similarity, respectively. Phylogenetic analyses, based on both nucleotide and amino acid sequence, resulted in three major groups among the avian reoviruses; these groups were clearly separated by species. The results of this study provide further evidence, based on the deduced sigma2 sequence, that turkey reoviruses form a distinct, separate group relative to chicken and duck isolates. In addition, as a result of the limited sequence identity with their avian counterparts, turkey reoviruses could potentially be considered a separate virus species within subgroup 2 of the Orthoreovirus genus. 相似文献