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81.
Souza LP Calegari F Zarbin AJ Marcolino-Junior LH Bergamini MF 《Journal of agricultural and food chemistry》2011,59(14):7620-7625
A direct determination of gallic acid was achieved at a carbon paste electrode modified with carbon nanotubes under differential pulse voltammetry conditions. The values obtained for gallic acid were used to estimate the antioxidant properties of the wine sample based on gallic acid oxidation. The proposed method is based on the gallic acid oxidation process at a modified carbon paste electrode (MCPE) containing 30% (m/m) of carbon nanotubes monitored at 0.35 V versus Ag/AgCl (KCl 3 mol L(-1)). Using the optimized experimental conditions, the calibration curve for gallic acid was linear in the concentration range from 5.0 × 10(-7) to 1.5 × 10(-5) mol L(-1) with a detection limit of 3.0 × 10(-7) mol L(-1). The MCPE was successfully applied for the determination of the antioxidant capacity for red and white wine samples without interference of glucose and ascorbic acid, and the obtained results were compared with the standard spectrophotometric method. 相似文献
82.
Ediane Batista da Silva Bruna Daniella de Souza Silva Jerônimo Rafael Ruiz Leon André Kipnis Isabel K.F. de Miranda Santos Ana Paula Junqueira-Kipnis 《Veterinary journal (London, England : 1997)》2011,187(2):276-278
This study evaluated the Mycobacterium tuberculosis protein antigen MPT-51, the trimeric antigen 85 (Ag85) complex, and Bacillus Calmette-Guérin (BCG) in an indirect ELISA to diagnose bovine tuberculosis (TB) from serum samples. Serum was collected from 208 intra-dermal tuberculin test (ITT)-positive and 54 ITT-negative animals from a region where bovine TB is endemic. Using the Ag85 and BCG antigens, the indirect ELISA was able to discriminate ITT-positive from ITT-negative animals. This level of discrimination was not achieved when using the MPT-51 antigen. The highest sensitivity (Se) and specificity (Sp) of the test was found when BCG was used (Se, 82%; Sp, 91%). Further work in different epidemiological settings and with larger numbers of animals will be required to validate these findings. 相似文献
83.
Ananias Francisco Dias Júnior Ana Lúcia Martins Sodero Pincelli Ana Paula Camara da Silva álison Moreira da Silva Natália Dias de Souza Mario Tommasiello Filho José Otávio Brito 《林业研究》2021,42(6):2313-2321
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are nee... 相似文献
84.
NI Christensen PJ Canfield PA Martin MB Krockenberger DS Spielman KL Bosward 《Australian veterinary journal》2009,87(5):175-181
Objectives To determine (1) the common types of canine splenic disorders, and the breeds affected, that are diagnosed by cytopathological and histopathological examination in Sydney, Australia and (2) the accuracy of cytopathological examination compared with histopathological examination for the diagnosis of canine splenic disorders. Design 69 cytopathological and 51 histopathological diagnoses of canine splenic disorders presented to the Veterinary Pathology Diagnostic Services, The University of Sydney during 2006 and 2007 were tabulated and analysed; 17 cases examined both cytopathologically and histopathologically during 2001–07 were also analysed. Results The most common cytopathological diagnoses were benign disorders of growth, vascular disturbances and necrosis (29%), followed by no abnormalities detectable (28%), malignant neoplasms (20%), equivocal diagnoses (20%) and inflammatory disorders (3%). The most common breeds were Kelpie crosses and mixed breeds. The most common histopathological diagnoses were benign disorders of growth, vascular disturbances and necrosis (49%), followed by malignant neoplasms (43%) and inflammatory disorders (8%). The most common breeds were German Shepherd Dogs, Boxers and Maltese Terriers. Cytopathological and histopathological diagnoses were in complete agreement in 59% of cases, partial agreement in 29% and disagreement in 12%. Conclusion Benign disorders of growth, vascular disturbances and necrosis were the most commonly diagnosed canine splenic disorders, both cytopathologically and histopathologically. Kelpie crosses presented most frequently for cytopathological examination. German Shepherd Dogs were the most common breed diagnosed histopathologically with haemangiosarcoma. Although cytopathological and histopathological splenic examinations are complementary for diagnosis, this study has shown a high correlation for complete and partial agreement between the two. 相似文献
85.
M. A. Dita C. Waalwijk I. W. Buddenhagen M. T. Souza Jr G. H. J. Kema 《Plant pathology》2010,59(2):348-357
This study analysed genomic variation of the translation elongation factor 1α (TEF‐1α) and the intergenic spacer region (IGS) of the nuclear ribosomal operon of Fusarium oxysporum f. sp. cubense (Foc) isolates, from different banana production areas, representing strains within the known races, comprising 20 vegetative compatibility groups (VCG). Based on two single nucleotide polymorphisms present in the IGS region, a PCR‐based diagnostic tool was developed to specifically detect isolates from VCG 01213, also called tropical race 4 (TR4), which is currently a major concern in global banana production. Validation involved TR4 isolates, as well as Foc isolates from 19 other VCGs, other fungal plant pathogens and DNA samples from infected tissues of the Cavendish banana cultivar Grand Naine (AAA). Subsequently, a multiplex PCR was developed for fungal or plant samples that also discriminated Musa acuminata and M. balbisiana genotypes. It was concluded that this diagnostic procedure is currently the best option for the rapid and reliable detection and monitoring of TR4 to support eradication and quarantine strategies. 相似文献
86.
Corgozinho KB de Souza HJ Pereira AN Belchior C da Silva MA Martins MC Damico CB 《Journal of Feline Medicine and Surgery》2007,9(6):481-486
Fifteen cats were evaluated with urethral obstruction. Penile trauma by catheterization was the major indication for perineal urethrostomy. Ten cats had developed a urethral stricture and five had rupture of the urethra following medical management. All cats had abnormalities in penis and/or prepuce and/or scrotal sacs including hyperemia or swelling. Perineal urethrostomy was performed in all cases and they were evaluated for 6 months after surgery. Few complications were noted. Urinary tract infection was the most frequent complication observed. The clients considered their cats to have a good quality of life following surgery. 相似文献
87.
88.
The Alternaria Brown Spot, caused by Alternaria alternata, is a major fungal disease in some kinds of tangerines, tangor, mandarins and pomelos. In Brazil as well as worldwide, A. alternata can cause necrosis in fruits, branches and leaves, causing substantial profit loss. In the present research, in laboratory conditions and in the field, we evaluated the resistance to the fungus, in leaves and fruits, for 22 varieties and hybrids of tangerines. To this end, we evaluated genotypes belonging to the Germplasm Bank of the Estação Experimental de Citricultura de Bebedouro. The resistant genetic materials (found in leaves and fruits) represented four varieties of clementines (Citrus clementina); six varieties of mandarins (two belonging to C. reticulata, two to C. tangerina, one to C. deliciosa and one to C. nobilis); one tangelo (C. tangerina × C. paradisi); two mandarin hybrids (one resulting from crossing C. nobilis × C. deliciosa and the other from crossing C. clementina × C. reticulata); one tangor hybrid (C. clementina) and two satsuma hybrids (C. unshiu × C. deliciosa). We also determined a relation between the inoculation of leaves and fruits. The resistance and susceptibility following inoculation in leaves and fruits supports a relationship between these organs and the physiological responses observed for the evaluated genotypes. 相似文献
89.
Silvia Ribeiro de Souza e Silva Luiz Claúdio de Almeida Barbosa Beatriz King-Diaz Blas Lotina-Hennsen 《Pesticide biochemistry and physiology》2007,87(2):109-114
3,4-Seco-friedelan-3-oic acid was isolated from Maytenus imbricata (Celastraceae). At low concentrations it inhibited non-cyclic electron transport and ATP synthesis in spinach chloroplasts, i.e., it behaved as a Hill reaction inhibitor, and at high concentrations it acts as an uncoupler by enhancing uncoupled electron transport and Mg2+-ATPase activity. 3,4-Seco-friedelan-3-oic acid did not inhibit PSII electron transport from DPC to DCPIPox and photosystem I activity, but it enhanced from TMQH2 to MV, corroborating its action as uncoupler. It inhibits electron flow through PSII from water to sodium silicomolybdate. The whole results indicate that the 3,4-seco-friedelan-3-oic acid target is at the OEC complex enzyme, the donor side of PSII. The fluorescence decay data shows the formation of the K-band, which match this result, acting as inhibitor at the donor side of PSII and it as an uncoupler. 相似文献
90.
Studies of the putative transforming protein of the type I human T-cell leukemia virus 总被引:20,自引:0,他引:20
D J Slamon M F Press L M Souza D C Murdock M J Cline D W Golde J C Gasson I S Chen 《Science (New York, N.Y.)》1985,228(4706):1427-1430
The putative transforming protein of the type I human T-cell leukemia virus (HTLV-1) is a 40-kilodalton protein encoded by the X region and is termed p40XI. On the basis of both subcellular fractionation techniques and immunocytochemical analysis, it is now shown that p40XI is a nuclear protein with a relatively short half-life (120 minutes). It is synthesized de novo in considerable quantities in a human T-cell line infected with and transformed by the virus in vitro, and it is not packaged in detectable amounts in the extracellular virus. 相似文献