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1.
Camu-camu [Myrciaria dubia (HBK) McVaugh] is a small fruit native to the Amazonian rain forest. Its anthocyanin profile has now been investigated for the first time. Fruits from two different regions of the S?o Paulo state, Brazil, were analyzed. The major anthocyanins were isolated by high-speed countercurrent chromatography. HPLC-PDA, HPLC-MS/MS, and 1H NMR were used to confirm the identity of the main anthocyanins of camu-camu. Cyanidin-3-glucoside was identified as the major pigment in the fruits from both regions, representing 89.5% in the fruits produced in Iguape and 88.0% in those from Mirandópolis, followed by the delphinidin-3-glucoside, ranging between 4.2 and 5.1%, respectively. Higher total anthocyanin contents were detected in the fruits from Iguape (54.0 +/- 25.9 mg/100 g) compared to those from Mirandópolis (30.3 +/- 6.8 mg/100 g), most likely because of the lower temperatures in the Iguape region.  相似文献   
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The aim of this study was to evaluate dietary supplementation of different levels of dehydrated bocaiuva pulp (DBP) on the productive performance of laying quails, and on lipid oxidation, and quality in their eggs. A total of 120 quails were distributed in a completely randomized design with six treatments (0%, 0.1%, 0.2%, 0.3%, 0.4% and 0.5% of DBP), five replicates and four birds per experimental unit. To evaluate lipid oxidation, the eggs were collected on five consecutive days at the end of the trial and distributed in a completely randomized experimental design in a 6 × 5 factorial scheme (eggs from quails fed different levels of DBP × evaluated fresh and after 7, 14, 21 and 28 days). The antioxidant potential of diets was improved (p < 0.05) when the DBP was added estimated as 2,2'‐azinobis‐3‐ethylbenzothiazolin‐6‐sulfonic acid (ABTS) free radical scavenging capacity. No effect (p > 0.05) was observed on feed intake, hen‐day egg production and feed conversion (kg/kg and kg/dz). There were no changes (p > 0.05) in the egg weight, Haugh unit, yolk index or eggshell percentage. Although no difference was observed (p > 0.05), when comparing each level with the control, a negative linear effect (p < 0.05) on specific gravity was observed. In addition, only the treatment with 0.5% pulp exhibited lower (p < 0.05) eggshell thickness compared with the control (0%). Thiobarbituric acid reactive substances (TBARS) analysis showed that as the dietary pulp level was increased, malondialdehyde content decreased linearly (p < 0.05) in the egg yolks, regardless of the storage period. Inclusion of DBP in the diets had no effect (p > 0.05) on the concentration of conjugated dienes in the eggs. The diets containing DBP showed a potential antioxidant effect, reducing the degree of lipid oxidation in egg yolk. However, no beneficial effects were observed on performance and egg quality.  相似文献   
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In Argentina, Thecaphora frezii is the causal agent of peanut smut, causing severe yield losses in peanut growing areas. In this work sequence data of the large ribosomal subunit (28S rDNA) of four T. frezii specimens from different production regions are provided. A fragment of about 650 bp was amplified by PCR from each of the isolates analyzed. The analysis of the sequences demonstrated 100 % identity among the four specimens and 92–96.3 % identity with sequences of other species of Thecaphora. This is the first study on molecular sequences of this pathogen.  相似文献   
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Soil biological response to management is best evaluated in field-scale experiments within the context of the soil environment and crop; however, cost-effective methods are lacking to relate these data which span multiple spatial scales. We hypothesized that zones of apparent electrical conductivity (ECa) could be used to integrate soil properties (sampling-site scale), microbial-scale measures of vesicular-arbuscular mycorrhizal (VAM) fungi, and field-scale wheat yields from yield maps. An on-farm dryland experiment (250 ha) was established wherein two (32-ha) fields were assigned to each phase of a winter wheat (Triticum aestivum L.) – corn (Zea mays L.) – proso millet (Panicum miliaceum L.) – fallow rotation. Each field was mapped and classified into four zones (ranges) of ECa. Soil samples were collected from geo-referenced sites within ECa zones and analyzed for multiple soil properties associated with productivity (0–7.5 and/or 0–30 cm). Additionally, VAM fungi were assessed using C16:1(cis)11 fatty acid methyl ester biomarker (C16vam), glomalin immunoassay, and wet-aggregate stability (WAS) techniques (1–2mm aggregates from 0- to 7.5-cm soil samples). Concentrations of C16vam and WAS increased among cropping treatments as: fallow < wheat < corn < millet. Glomalin across crops and replicates, C16vam and WAS in fallow (crop effect removed), soil properties associated with productivity, and wheat yields were negatively correlated with ECa and different among ECa zones (P 0.05). Zones of ECa provide a point of reference for relating data collected at different scales. Monitoring cropping system parameters and profitability, over time, may allow linkage of microbial-scale processes to farm-scale economic and ecological outcomes.  相似文献   
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Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. Heterofucan SF-1.5v was extracted from the brown seaweed Sargassum filipendula by proteolytic digestion followed by sequential acetone precipitation. This fucan showed antiproliferative activity on Hela cells and induced apoptosis. However, SF-1.5v was not able to activate caspases. Moreover, SF-1.5v induced glycogen synthase kinase (GSK) activation, but this protein is not involved in the heterofucan SF-1.5v induced apoptosis mechanism. In addition, ERK, p38, p53, pAKT and NFκB were not affected by the presence of SF-1.5v. We determined that SF-1.5v induces apoptosis in HeLa mainly by mitochondrial release of apoptosis-inducing factor (AIF) into cytosol. In addition, SF-1.5v decreases the expression of anti-apoptotic protein Bcl-2 and increased expression of apoptogenic protein Bax. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer.  相似文献   
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ABSTRACT

Volumetric yield analysis is critical to optimizing performance in the timber industry. In the Amazon and in the Amapá state, this information is still little known and scarce, and therefore this study was developed to obtain and analyze the volumetric yield coefficient of ten commercial tree species and to test the variation by diameter class. We collect data of volumetric yield from for ten commercial species. For each species, the yields in different diameter classes were analyzed, as well as the yield difference between the species. The overall yield obtained for the sawmills (43.95%) and the yield of each species are within the established standards for operations in the industry according to the legal requirements. There were no differences (p ≥ 0.05) in diameter classes for species with the exception of Dinizia excelsa and Handroanthus albus. However, there was no linear increase (p ≥ 0.05) between the diameter and yield of lumber for all species. The species Dinizia excelsa, Hymenolobium petraeum, Ocotea rubra and Vochysia guianensis show a significant difference in yield for the other species due to the higher obtained values, however, they are statistically similar when compared to each other.  相似文献   
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The aim of this study was to evaluate lipid peroxidation, protein oxidation and activity of enzymes that are indicators of oxidative stress in Rangelia vitalii infection in dogs. Animals were divided into two groups: negative control (n=5) and infected with R. vitalii (n=7). After inoculation, the parasitemia was estimated daily by microscopic examination of smears. Lipid peroxidation (TBARS) and advanced oxidation protein products (AOPP); and delta-aminolevulinate dehydratase (δ-ALA-D), superoxide dismutase (SOD) and catalase (CAT) activities in blood were evaluated. The samples were collected at days 10 and 20 post-inoculation (PI). TBARS and AOPP levels were higher in the infected group in both analyzed periods (P<0.01). The δ-ALA-D activity was reduced in blood of dogs infected with R. vitalii on days 10 and 20 PI. SOD activity was significantly increased (P<0.01) in the blood of dogs infected with R. vitalii at days 10 and 20 PI, while CAT activity was significantly increased (P<0.01) only at day 20 PI when compared to non-infected animals. A positive correlation was observed between the degree of parasitemia and TBARS and AOPP levels and activity of antioxidant enzymes. The δ-ALA-D activity was negatively correlated with the degree of parasitemia. Based on the increased levels of TBARS, AOPP, SOD and CAT activities, and inhibition δ-ALA-D activity, we concluded that dogs experimentally infected with R. vitalii develop a state of redox unbalance and that these changes might be involved in the pathophysiology of disease.  相似文献   
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