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131.
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A rapid method for the extraction and monitoring of picogram level of silver ions using uniform silanized mesopor (MCM-41) modified by a thiocompound and inductively coupled plasma atomic emission spectrometry (ICP-AES) is presented. The preconcentration factor of the method is 500, and detection limit of the technique for silver is 6.5 pg/ml. The time and the efficiency of the extraction, pH and flow rate, type and minimum amount of acid for stripping of silver from modified MCM-41 was tested. The break through volume of the method was found 2500 ml. The maximum capacity the modified MCM-41 was found to be 11.0 ± 1.2 μg of Ag+/mg modified MCM-41.  相似文献   
133.
A reliable method for measuring disease progression is important when evaluating susceptibility in host—pathogen interactions. We describe a sensitive quantitative polymerase chain reaction (QPCR) assay that enables quantitative measurement of in planta DNA of the necrotrophic pathogen, Phytophthora cinnamomi, that avoids problems caused by variation in DNA extraction efficiency and degradation of host DNA during host tissue necrosis. Normalization of pathogen DNA to sample fresh weight or host DNA in samples with varying degrees of necrosis led to overestimation of pathogen biomass. Purified plasmid DNA, containing the pScFvB1 mouse gene, was added during DNA extraction and pathogen biomass was normalized based on plasmid DNA rather than host DNA or sample fresh weight. This method is robust and improves the accuracy of pathogen measurement in both resistant (non-host A. thalianaP. cinnamomi) and susceptible (host Lupinus angustifoliusP. cinnamomi) interactions to allow accurate measurement of pathogen biomass even in the presence of substantial host cell necrosis.  相似文献   
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135.
Neosporosis and toxoplasmosis are two important infections in young and adult sheep, leading to low production and abortion. This study aimed to determine the frequency of antibodies to Toxoplasma gondii and Neospora caninum in sheep from the eastern region of S?o Paulo State, Brazil. Serum samples (382) were collected from the sheep and assayed for T. gondii through modified agglutination test (MAT) and indirect fluorescent antibody test (IFAT), and for N. caninum antibodies, through IFAT, with cut-off titers equal to 16 (T. gondii) and 25 (N. caninum). All frozen samples were sent to the Center for Zoonoses Research (NUPEZO), Department of Veterinary Hygiene and Public Health (DHSVP), FMVZ, UNESP, for serological tests. A total of 71/382 (18.6%) samples reacted to T. gondii, especially at titers 16 (28; 39.4%), 64 (15; 21.1%), 256 (21; 29.6%) and 1024 (6; 8.5%) by MAT, and 16 (34; 47.9%), 64 (18; 25.4%), 256 (14; 19.7%) and 1024 (5; 7%) by IFAT. As regards N. caninum, 49/382 (12.8%) samples reacted at titers 25 (17; 34.7%), 50 (11; 22.5%), 100 (11; 22.5%), and ≥ 200 (10; 20.4%). These animals presented infection but no clinical signs. Six and ten animals had high titers for toxoplasmosis and neosporosis. No significant association was observed between antibodies for both parasites (P=0.535) according to Fisher's exact test, and no correlation was found between T. gondii (MAT) and N. caninum antibody titers (r=-0.0068; P=0.895), T. gondii (IFAT) and N. caninum antibody titers (r=-0.0025; P=0.961). Thus, T. gondii and N. caninum infections were observed in farms located in S?o Paulo State, where sheep play an important economical role for the national and regional business.  相似文献   
136.
Tropical Animal Health and Production - Since 1998, Iran’s poultry industry has faced several outbreaks of low pathogenic avian influenza H9N2. Tissue samples were collected from a broiler...  相似文献   
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138.
The generalist predatory mite, Neoseiulus cucumeris (Oudemans) is known as one of the most effective natural enemies on many pests. This economically important biocontrol agent was reared for 20 generations on date palm and castor bean pollen as well as a mixture of pollen types, including date palm, castor bean, and almond. The performance of this predator was evaluated by comparing its life table parameters after different generations (G1–G20) fed on each diet in a laboratory at 25 ± 1°C, 60 ± 5% RH, and a photoperiod of 16:8 (L: D) h. The development time of the predator reared on all tested diets had no significant difference in G20. The intrinsic rate of increase (r) of N. cucumeris by feeding on the mixed pollen (0.197 day−1) was significantly higher than that on castor bean, or date palm pollen (0.146 or 0.152 day−1 in G1, respectively). Our results indicated that the predator’s performance was not affected by long-term feeding on the pollen diets, as well as there was no considerable difference between pollen alone and pollen mixture diets. Furthermore, mites reared on pollen diets had higher quality than those reared on natural prey, Tetranychus urticae Koch.  相似文献   
139.
Carbohydrates are thought to function as tags that mark circulatory glycoproteins for rapid clearance. To examine the role of the mannose receptor (MR) in glycoprotein clearance, we generated mice genetically deficient in MR. MR-/- mice were defective in clearing proteins bearing accessible mannose and N-acetylglucosamine residues and had elevated levels of eight different lysosomal hydrolases. Proteomic analysis of MR-/- and control mouse sera showed that an additional 4 out of 52 proteins identified were elevated in MR-/- serum. Each of these is up-regulated during inflammation and wound healing. Thus, MR appears to operate as an essential regulator of serum glycoprotein homeostasis.  相似文献   
140.
This work was carried out to study the effects of two soilless media consisting of 80:20 [volume/volume (v/v)] mixtures of mosspeat and perlite, or cocopeat and perlite, on fruit quality and anti-oxidant activities in four cultivars of bell pepper (Capsicum annuum L.): ‘Traviata’ (green), ‘Inspratian’ (red), ‘Aracia’ (orange), and ‘Taranto’ (yellow). The results showed that the composition of the medium had a significant effect on the anti-oxidant composition and activities of the bell pepper fruit. Plants grown on 80:20 (v/v) mosspeat and perlite had significantly higher pericarp firmness, titratable acidity, total phenolic compound concentrations, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, and the hydroxy free-radical (?OH) scavenging ability. Fruit on plants grown on 80:20 (v/v) cocopeat and perlite had significantly higher vitamin C concentrations. Among the four cultivars tested, ‘Inspratian’ (red) was superior in more factors including pericarp thickness, dry matter content, titratable acidity, total soluble solids content, total phenolic concentration, DPPH scavenging ability, and vitamin C concentration. There was a significant interaction between cultivar and soilless medium composition, indicating that the response of bell pepper cultivars varied in the different media. The results of the present study highlight the importance of comparing soilless media in terms of their effect on fruit crop quality and anti-oxidant activity.  相似文献   
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