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51.
OBJECTIVE: To determine whether use of topical flea and tick products increases the risk of transitional cell carcinoma (TCC) of the urinary bladder in Scottish Terriers. DESIGN: Case-control study. ANIMALS: 87 adult Scottish Terriers with TCC (cases) and 83 adult Scottish Terriers with other health-related conditions (controls). PROCEDURE: Owners of study dogs were recruited through private veterinary practices and the Scottish Terrier Club of America. History of exposure to flea and tick products 1 year prior to diagnosis of TCC for case dogs and during a comparable period for control dogs was obtained through a questionnaire. Risk of TCC associated with exposure to flea and tick products was determined by means of univariate and multiple logistic regression analysis. RESULTS: After adjustment for host factors, Scottish Terriers treated with topical spot-on flea and tick products containing fipronil or imidacloprid did not have an increased risk of TCC, compared with Scottish Terriers that had never been exposed to any flea and tick products. The risk of TCC associated with use of older topical flea and tick products such as shampoos, dips, powders, sprays, and collars could not be evaluated because of the low number of owners in the study population that had used such products. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that use of topical spot-on flea and tick products does not increase the risk of TCC in Scottish Terriers.  相似文献   
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Ninety-five jackfruit types selected from Western Ghats of India, which is the centre of origin for the species, were analyzed using Mahalanobis D2 technique to determine the degree of divergence present among the selections. The studies revealed that majority of selections (91), irrespective of their ecogeographic area, were grouped in one cluster and the remaining 4 types were solitary with one selection in each cluster. Inter cluster distance was maximum between clusters D and E (525.8) and minimum inter cluster divergence was observed between clusters B and C (106.1). Cluster means for all economically important characters were not found to be highest in any one cluster indicating the vast diversity on account of indigenous and cross-pollinated nature of the crop. The maximum relative contribution to the total divergence was by number of seeds per fruit and TSS:Acid ratio indicating the ample amount of variability in these traits and hence the selection process for crop improvement in jackfruit should deem these characters.  相似文献   
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Eleven Newcastle disease viruses (NDV), isolated from apparently healthy and ailing Desi chickens were subjected to both conventional and modern characterization techniques. The virulence and strain differentiating experiments placed 10 isolates in the velogenic group and one in the mesogenic group. In MDBK cells, 9 isolates produced characteristic cytopathogenic effects up to 5 and 2 up to 3 passages. Molecular characterization with a 21-mer oligonucleotide probe placed all the isolates in the velogenic/mesogenic group. The results of this study clearly indicated that the isolates obtained are either velogenic or mesogenic but not lentogenic.  相似文献   
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Enzymatically hydrolyzed fish protein hydrolysates could be used as a source of antioxidative nutraceuticals. In our current work, we have investigated alkali-solubilized tilapia ( Oreochromis niloticus) protein hydrolysates for their ability to scavenge reactive oxygen species (ROS) and for their reducing power. Tilapia protein isolate was prepared by an alkaline solubilization technique and used as a substrate for enzyme hydrolysis. Cryotin, protease A 'Amano' 2, protease N 'Amano', Neutrase and Flavourzyme, were used separately to determine their effectiveness in hydrolyzing tilapia protein isolate. ROS scavenging ability was quantified using an isoluminol enhanced chemiluminescent assay in the presence of a) hydrogen peroxide or b) mononuclear cells isolated from human blood. Ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) of the hydrolysates using 2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) or 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), were also investigated. Results showed that, in general, the TEAC, FRAP values and ROS scavenging ability of the hydrolysates increased with an increase in the degree of hydrolysis. Among the different hydrolysates, those prepared using Cryotin were most effective and Amano A2 hydrolysates were least effective in scavenging ABTS*(+) and ROS generated by hydrogen peroxide. However, FRAP assay showed that hydrolysates prepared using Flavourzyme were most effective, and Amano N and Neutrase hydrolysates were least effective in reducing ferric ions. No significant difference was observed among the hydrolysates produced with different enzymes in their ability to scavenge ROS generated by phorbol myristate acetate stimulated mononuclear cells. These results shed light on the in vitro ROS scavenging ability of alkali solubilized tilapia protein hydrolysates, as well as potential nutraceutical use of these hydrolysates.  相似文献   
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The significance of plant growth-promoting rhizobacteria (PGPR) mediated increase in antioxidant potential in vegetables is yet unknown. The plant growth-promoting bacterium Bacillus lentimorbus NRRL B-30488 (B-30488) mediated induction of dietary antioxidant in vegetables ( Trigonella foenum-graecum, Lactuca sativa, Spinacia oleracea, and Daucus carota) and fruit ( Citrus sinensis) after minimal processing (fresh, boiled, and frozen) was tested by estimating the total phenol content, level of antioxidant enzymes, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide scavenging activities along with integral radical scavenging capacity by photochemiluminescence assay and inhibition of lipid peroxidation. Minimal processing of vegetables showed that T. foenum-graecum had the highest phenol content in B-30488-treated plants followed by L. sativa, D. carota, and S. oleracea. Thermally treated vegetables T. foenum-graecum (26-114.5 GAE microg mg (-1)) had an exceptionally high total phenolic content, followed by D. carota (25.27-101.32 GAE microg mg (-1)), L. sativa (23.22-101.10 GAE microg mg (-1)), and S. oleracea (21.87-87.57 GAE microg mg (-1)). Among the vegetables and fruit used in this study for enzymatic estimation, induction of antioxidant enzymes, namely, polyphenol oxidase (PPO), ascorbate peroxidase (APX), catalase (CAT), and superoxidase dismutase (SOD), was observed in edible parts of T. foenum-graecum, L. sativa, S. oleracea, and D. carota, after inoculation with B-30488. The scavenging capacity of the vegetables treated with B-30488 against DPPH and superoxide anion radical activity was found to be significantly high as compared to nontreated control. Mild food processing had no adverse effect on radical scavenging capacity. Photochemiluminescence also ascertains the above findings. The ability of the plant extracts to protect against lipid peroxidation and its ability to prevent oxidation of reduced glutathione (GSH) was measured in rat liver homogenate, and the results suggested that the inoculated plant exhibited better activity in all of the screened plants. Significant increases in shoot length, root length, and dry weight, averaging 164, 132, and 135% in T. foenum-graecum, 174, 141, and 156% in L. sativa, 129, 141, and 59%, in S. oleracea, and 125, 146, and 42% in D. carota, respectively, over untreated controls, were attained in greenhouse trials. To the best of the authors' knowledge, this is the first report of PGPR-mediated induction of antioxidant enzyme activity (PPO, APX, CAT, and SOD) along with the antioxidant activity of the extracts in both in vitro (DPPH radical scavenging and superoxide scavenging) and ex vivo conditions using the rat liver tissue (percent inhibition of lipid peroxidation and prevention of oxidation of GSH) and phenolic content. The results demonstrate the PGPR-mediated induction of antioxidant level in vegetables and fruit controls oxidative damage even after minimal processing and thus is indicative of its potential as a viable substitute of synthetic antioxidants.  相似文献   
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The effects of food availability on the larval growth and survival of Paphia malabarica were studied in two experiments by feeding the larvae with six algal diets. Newly hatched larvae of P. malabarica were fed with six different marine microalgae species, singly and in a combination of two species. The best growth was with Isochrysis galbana and Nannochloropsis salina as a single species of diet. The nutritional value of single‐species diets was in the order of N. salina, I. galbana, Dicrateria inornata, Chaetoceros calcitrans, Tetraselmis gracilis and Dunaliella salina. Of the mixtures tested, 50%I. galbana/50%N. salina supported growth and metamorphosis equivalent to those of the I. galbana control.  相似文献   
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Associations of land cover/land use variables and the presence of dogs in urban vs. rural address locations were evaluated retrospectively as potential risk factors for canine leptospirosis in Kansas and Nebraska using Geographic Information Systems (GIS). The sample included 94 dogs positive for leptospirosis predominantly based on a positive polymerase chain reaction test for leptospires in urine, isolation of leptospires on urine culture, a single reciprocal serum titer of 12,800 or greater, or a four-fold rise in reciprocal serum titers over a 2-4 weeks period; and 185 dogs negative for leptospirosis based on a negative polymerase chain reaction test and reciprocal serum titers less than 400. Land cover features from 2001 National Land Cover Dataset and 2001 Kansas Gap Analysis Program datasets around geocoded addresses of case/control locations were extracted using 2500m buffers, and the presence of dogs' address locations within urban vs. rural areas were estimated in GIS. Multivariate logistic models were used to determine the risk of different land cover variables and address locations to dogs. Medium intensity urban areas (OR=1.805, 95% C.I.=1.396, 2.334), urban areas in general (OR=2.021, 95% C.I.=1.360, 3.003), and having urban address locations (OR=3.732, 95% C.I.=1.935, 7.196 entire study region), were significant risk factors for canine leptospirosis. Dogs regardless of age, sex and breed that live in urban areas are at higher risk of leptospirosis and vaccination should be considered.  相似文献   
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A real-time, volatile-detection-assisted control system was designed for microwave drying. Detected volatile signals were integrated to a fuzzy logic algorithm to determine the drying temperature. A phase controller was used to automatically and continuously adjust the microwave power. A data acquisition unit with developed program was employed to integrate the entire control. Carrot samples were used in system tests. The results showed that the designed system could successfully achieve the desired temperature, power, and volatiles control and lead to acceptable product's quality.  相似文献   
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