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排序方式: 共有1935条查询结果,搜索用时 15 毫秒
981.
Lílian da Silva Fialho Valéria Monteze Guimarães Everaldo Gonçalves de Barros Maurilio Alves Moreira Luiz Antônio dos Santos Dias Maria Goreti de Almeida Oliveira Inês Chamel José Sebastião Tavares de Rezende 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):83-85
Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02–60.17%), GO (3.12 – 5.71%), protein (22.17–33.50%), lipid (1.13–1.81%), moisture (11.42–12.93%) and ash contents (4.08–5.61%). ‘Mexico 222’ presented the highest α-galactosidase activity. Protein and GO contents were positively correlated. ‘Perry Marrow’ combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. 相似文献
982.
Ivan Rui Lopes Albuquerque Sara Lima Cordeiro Dayanne Lopes Gomes Juliana Luporini Dreyfuss Luciana Guimar?es Alves Filgueira Edda Lisboa Leite Helena Bonciani Nader Hugo Alexandre Oliveira Rocha 《Marine drugs》2013,11(8):2722-2740
Fucan is a term that defines a family of homo- and hetero-polysaccharides containing sulfated l-fucose in its structure. In this work, a heterofucan (F2.0v) from the seaweed, Dictyota menstrualis, was evaluated as an antinociceptive and anti-inflammatory agent. F2.0v (20.0 mg/kg) inhibits 100% of leukocyte migration into the peritoneal cavity after chemical stimulation. However, F2.0v does not alter the expression of interleukin-1 beta (IL-1β) and interleukin-6 (IL-6), as well as tumor necrosis factor alpha (TNF-α). F2.0v (20.0 mg/kg) has peripheral antinociceptive activity with potency similar to dipyrone. On the other hand, it had no effect on pain response on the hot plate test. Confocal microscopy analysis and flow cytometry showed that F2.0v binds to the surface of leucocytes, which leads us to suggest that the mechanism of action of anti-inflammatory and antinociceptive F2.0v is related to its ability to inhibit the migration of leukocytes to the site of tissue injury. In summary, the data show that F2.0v compound has great potential as an antinociceptive and anti-inflammatory, and future studies will be performed to further characterize the mechanism of action of F2.0v. 相似文献
983.
Jörg Mayer Patrick Hensel Johanna Mejia-Fava João Brandão Stephen Divers 《Journal of Exotic Pet Medicine》2013,22(1):65-69
Fish lice can cause significant morbidity and death in heavily infested fish. In addition to being a mechanical irritant when sucking blood, Argulus sp have been shown to be the vector for other fish diseases. Koi carp from a pond environment were presented with multiple raised dark spots on their dorsa and sides. The primary differential disease diagnosis was an Argulus sp. Parasites removed from the affected fish were examined under a dissection microscope, and the definitive diagnosis was determined to be Argulus sp infestation. Treatment with lufenuron (Program; Novartis, Greensboro, NC USA) was initiated with one 409.8-mg tablet per 1,000 US gallons (3,785 L) of water for a concentration of approximately 0.1 mg/L. This treatment was repeated once per week for 5 weeks. The fish have been monitored for 13 months after the initial treatment, and thus far, there has been no reappearance of Argulus sp within the aquatic environment. 相似文献
984.
The anatomy of the avian gastrointestinal (GI) tract is unique and significantly different from that of other animals. The characteristics of the avian GI tract allow the different species to adapt and thrive in their habitats. Infectious diseases of bacterial, viral, fungal, and parasitic origin commonly affect avian species. The significance and the nature of these pathologies vary with species and if they live in the wild or a captive environment. This review compiles information available in the literature on specific infectious processes that were considered relevant and clinically significant by the authors. Clinicians should be knowledgeable and aware of the infectious agents, clinical signs associated with disease, diagnostic techniques, and treatment methodologies currently available regarding diseases that affect the avian GI tract. Recent information that provides new insight to these infectious processes is the focus of this article. 相似文献
985.
J. I. Fahl M. L. C. Carelli J. Vega A. C. Magalhães 《The Journal of Horticultural Science and Biotechnology》2013,88(1):161-169
SummaryShoot growth attributes, leaf anatomical changes and net photosynthetic rates were determined in young coffee plants fertilized at high and low levels and subjected to shade or full sunlight. High nitrogen supply increased plant height irrespective of the light level imposed during growth, and promoted a larger leaf area in plants of the shade treatment. Specific leaf weight was 15% higher in plants grown in full sunlight than in shaded plants, at both nitrogen levels. The number of leaves developed on the orthotropic stem increased significantly under full irradiance and high nitrogen availability. Leaves were 11% thicker ih unshaded plants than in shaded ones, because of the increased size of the palisade and spongy parenchyma tissues. More thylakoids per granum and more grana per chloroplast were observed in shade-grown plants, mainly in those given high nitrogen treatment. Total nitrogen content expressed on a leaf-area basis was higher in sun plants supplemented with nitrogen, whereas chlorophyll a and b and protochlorophyll contents increased in shade-grown plants. Net photosynthetic rate in high nitrogen plants reached 7.19 µmol CO2 m?2 s?1 in the full irradiance treatment, and 5.46 µmol CO2 m?2 s?1 in shaded plants. Maximum net photosynthetic rates in the low nitrogen plants were 5.28 and 4.90 µmol CO2 m?2 s?1 in sun and shade plants, respectively. Increased photosynthetic light saturation was observed in high irradiance plants (628 µmol m?2 s?1) relative to shade plants (359 µmol m?2 s?1) in the high nitrogen treatment. The same pattern was observed in low nitrogen plants. The apparent quantum yield of shade acclimated plants was 14% higher than in those grown in full sunlight. Our results indicate that coffee may be classified as a facultative shade species, exhibiting features of sun adapted plants coupled with shade acclimation attributes, this fairly high adaptive capacity to shade:sun transition being strongly influenced by the level of nitrogen nutrition given to the plants. 相似文献
986.
Matheus Costa Dos Reis Fernando Lisboa Guedes Guilherme Barbosa Abreu João Cândido de Souza 《Euphytica》2013,191(2):217-222
The objective of the research was to evaluate recurrent selection strategies in maize (Zea mays L.) by determining the expected and realized responses to selection, as well as the alterations in heterosis, of hybrids from the cross between the original populations (C0) and the third cycle (C3). The genetic variances and covariances were obtained for intrapopulational (P11 and P22) and interpopulational (P12 and P21) half-sib progenies from populations 1 and 2 in cycles C0 and C3. One-hundred progenies of each type were evaluated [husked ear weight (g plant?1)] at two separate locations by conducting 10 × 10 triple lattice design experiments contiguous for each cycle. Four different recurrent selection strategies were investigated: reciprocal recurrent selection (RRS), interpopulation testcross half-sib selection (THS 1 and THS 2) and intrapopulational half-sib recurrent selection (HSS). THS 1, which employed population 1 (with the lowest frequency of favorable alleles) as tester, was most efficient in the simultaneous improvement of the hybrid and the two populations per se. RRS showed the highest efficiency in improving the interpopulational hybrid but not in the parental populations. In order to estimate heterosis and realized responses to RRS, representative samples of seed from intra and inter-populational half-sib progenies from C0 and C3 were employed in randomized block design experiments with 10 repetitions carried out at two separate locations. RRS increased heterosis in the interpopulational hybrid from 12.3 % (C0) to 24.9 % (C3), and the productivity gain [husked ear weight (t ha?1)] was 13.5 % over the three cycles. 相似文献
987.
María Xesús Gómez-Rey Manuel Madeira João Coutinho 《European Journal of Forest Research》2013,132(2):281-295
Wood ash addition to forest soils can balance exported nutrients by tree harvesting and decrease soil acidity, but its effectiveness in Mediterranean areas has been scarcely evaluated. The aim of the present study was to assess the effects of wood ash application on soil C and N dynamics, nutrient leaching and fertility in a pine stand. Treatments were loose and pelleted ash application (11 Mg ha?1), alone or combined with N fertilizer, and a control treatment. Nutrient leaching and soil chemical and biological properties were periodically evaluated for a 30-month period. Wood ash increased leaching of base cations (Ca, Mg, Na and K) and P, mainly at the beginning of the study. The effect was more pronounced for the loose formulation. As a consequence, a positive effect on soil nutrient availability (exchangeable base cations and extractable P) and soil acidity reduction was observed for the loose formulation in the 0–10-cm soil layer. Carbon and N dynamics were only affected when ash was applied with N fertilizer, which enhanced CO2 flux during the study period. 相似文献
988.
Joo de Magalhes Lopes Paulo Santos Pompeu Carlos Bernardo Mascarenhas Alves Alexandre Peressin Ivo Gavio Prado Fbio Mineo Suzuki Susanne Facchin Evanguedes Kalapothakis 《Ecology of Freshwater Fish》2019,28(2):302-316
Biotelemetry, ichthyoplankton and genetic data can provide detailed information about the migratory dynamics and reproductive cycle of freshwater fishes. However, few studies have combined these techniques in Neotropical systems. The objective of this study was to examine the migratory and reproductive dynamics of Prochilodus costatus in the São Francisco River watershed, south‐east Brazil, by comparing the ecological importance of two rivers to the species, an undammed segment of the São Francisco River and a dammed segment of one of its main tributaries, the Pará River. In total, 215 fish were radio‐tagged over three years (2014–16). Eggs and larvae were sampled at seven locations and analysed by PCR to identify Prochilodus spp. ichthyoplankton. Most radio‐tagged individuals (97%) used the undammed segment of the São Francisco River as spawning migration route, even those captured and released in the Pará River. Fish migrated to spawn from late September to late November with the arrival of the rains and returned to feeding sites from December to May after spawning. The highest densities of fish eggs and larvae were recorded in the upper reaches of the São Francisco River during months of peak river discharge. Returning fish showed high fidelity to sites occupied before spawning migration. Fish spent roughly 71% of the year at feeding sites, 25% at spawning sites and 4% moving between them. This study provides novel information about the migratory dynamics of Neotropical fishes and underscores the key role of undammed river segments for the conservation of Neotropical migratory fish species. 相似文献
989.
990.
Eva Pinho Mariana Henriques Rosário Oliveira Alberto Dias Graça Soares 《Fibers and Polymers》2010,11(2):271-276
The goal of this work was to create a new generation of greener fabrics made of natural materials. For that, resveratrol (Res),
obtained from Polygonum cuspidatum extract and known to have antibacterial, antifungal, and anti-inflammatory activity, was applied by an exhaustion method
to cotton, bamboo, and silk knit fabrics. The fabrics adsorption behavior was tested and the amount of Res adsorbed was determined
by its decrease on the immersion solutions with time and measured by spectrophotometry at 350 nm. The maximum adsorption capacity
was observed for silk and it was independent of pH conditions used (50.5 % at pH=7 and 58.3 % at pH=5 of the initial Res concentration).
At acidic pH conditions, cotton adsorbed 51.2 % of Res and Bamboo adsorbed only 28.1 % in 15 min. However, neither cotton
nor bamboo adsorbed Res at pH=7. The release behavior was also analyzed and the highest Res release was observed for cotton
in alkaline sweat and urine mimic solutions. The lowest release was achieved by cotton in water (1.0 ng/ml). Moreover, no relation was found between the amounts of Res adsorbed or released and cell viability. In conclusion, this
work shows that it is possible to obtain cotton, bamboo, and silk functionalized with resveratrol. The incorporating process
here described is simple and silk-Res can be presented as a good combination. 相似文献