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131.
Protected tomato is the most important horticultural crop in the Algarve (south of Portugal). However, the growing area has decreased by almost 48% since 1995, mainly as a result of the pests Bemisia tabaci and Trialeurodes vaporariorum and the epidemics of Tomato yellow leaf curl virus (TYLCV), a Begomovirus transmitted by B. tabaci. Both whiteflies are vectors of economically important viruses. Recently, Tomato chlorosis virus (ToCV), a member of the genus Crinivirus, transmitted by both B. tabaci and T. vaporariorum, was reported infecting tomato crops in Algarve. A study was carried out to evaluate the dynamics of whitefly populations on tomato crops in Algarve. Population counts of B. tabaci were high in the first months of autumn, then decreased until January, when numbers of T. vaporariorum became higher. Counts of B. tabaci then increased again.  相似文献   
132.
The whitefly Bemisia tabaci has been a serious pest in protected tomato crops since 1995 in the south of Portugal (Algarve), causing severe losses mainly resulting from Tomato yellow leaf curl virus (TYLCV), first reported in the autumn/winter season. In order to manage and control the B. tabaci/TYLCV complex, experimental field trials were carried out between 1997 and 2000. Several control methods were tested, such as the application of white screen nets to windows and doors, chemical treatments against B. tabaci and the use of cucumber as a trap crop. The results show that the percentage of plants with TYLCV symptoms mainly reflects B. tabaci infestation level in the first 6 weeks. Screen net protection was the control method that clearly provided a low incidence of plants with TYLCV symptoms in the autumn/winter season. Additionally, insecticide treatments, made weekly in the first 6 weeks, may give improved protection. In the winter/spring season, the B. tabaci/TYLCV complex is a minor problem because of the low populations of B. tabaci and the climatic conditions. Information about the work in progress and results was given to growers through visits to the experimental fields and oral presentations.  相似文献   
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Objective— To evaluate the efficacy of cryosurgery for treatment of skin and subcutaneous tumors in dogs and cats.
Study Design— Prospective study.
Animals— Dogs (n=20), cats (10).
Methods— Cutaneous or subcutaneous tumors were treated by liquid nitrogen cryosurgical spray (1 cm from target tissue at 90° until a 5-mm halo of frozen tissue was achieved) for 15–60 seconds. Malignant lesions had 3 freeze–thaw cycles benign tumors, 2 cycles. The second or third freeze cycle was performed after complete thaw of the preceding freeze. Wounds healed by second intention. Follow-up was weekly for 1 month and then twice monthly until wounds healed, and final outcome was determined by telephone interview of owners.
Results— Tumor size ranged from 0.3 to 11 cm diameter with 28 (60%) being 0.3–1 cm; 8 (17%) 1.1–3 cm, and 11 (23%) >3.4 cm. Complications included edema, erythema and for extremity lesions, pain and lameness. Treated lesions (n=47) had an overall remission of 98% (mean follow-up, 345±172.02 days [range, 150–750 days]). One malignant peripheral nerve sheath tumor recurred 7 months after cryosurgical treatment.
Conclusion— Cryosurgery is an efficient method for treatment of skin and subcutaneous tumors in dogs and cats.
Clinical Relevance— Cryosurgical ablation is an effective means of treating small cutaneous or subcutaneous tumors in dogs and cats, especially in older animals where wound closure or cosmetic outcome might limit surgical excision alone.  相似文献   
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Water, Air, & Soil Pollution - Laboratory snow melting experiments were conducted with actual late-winter snow samples, collected just before the final snowmelt, in two similar northern Swedish...  相似文献   
135.
This study aimed to investigate the efficiency of turmeric (Curcuma longa L.) extract, applied as a marinade or glaze, as an antioxidant for frozen streaked prochilod (Prochilodus lineatus) fillets. The turmeric extract contained 5.5 ± 0.1 mg curcumin/mL, and the experiment was performed using a diluted extract with 100 µg curcumin/mL. Analysis of the antioxidant activity with 2,2-diphenyl-picrylhydrazyl (DPPH) and 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals confirmed the high antioxidant activity of curcumin. However, under the experimental conditions, curcumin extract presented no effectiveness for inhibiting lipid oxidation in frozen streaked prochilod fillets, as the concentration of thiobarbituric acid reactive substances did not differ (p > 0.05) between treated and control fillets. Sensory evaluation of the fillet appearance indicated that the change toward a more yellow color in treated fillets negatively affected its acceptance. However, the acceptability of the odor of raw and cooked fillets was similar for treated and control samples. These results may be explained by the fact that good in vitro performance of antioxidants is not always replicated in foodstuffs owing to the complexity of food matrices. Additionally, the low lipid content of the fish and the low amount of curcumin applied to the fillets may have contributed to the inefficiency of turmeric extract.  相似文献   
136.
This 45‐day work aimed to determine the response of juvenile pacu (Piaractus mesopotamicus) to balanced digestible protein (BDP) and to use these responses to determine whether the optimum economic levels of BDP would differ depending on the form in which the fish is sold. Six isoenergetic diets containing 163, 201, 238, 272, 315 and 348 g/kg BDP (dry‐matter basis) were prepared through the serial dilutions of a high‐protein diet with the low‐protein diet. Fish (initial average body weight, 10.82 ± 0.14 g) were fed with respective experimental diets three times a day until apparent satiation. The optimum biological level of BDP was calculated as 326 g/kg (dry‐matter basis) by the quadratic regression model for maximum body weight gain of juvenile pacu. To maximize economic returns (US$/kg) for different end products, the optimum economic levels of BDP were calculated as 311, 317 and 319 g/kg (dry‐matter basis) by an economic model for whole‐body, eviscerated and sliced juvenile pacu respectively. This finding revealed that obtaining maximum biological performance of fish in the case of high feed costs or low prices of the end product in consumer market would substantially reduce the economic returns.  相似文献   
137.
The present study was conducted to administer a commercial multi‐strain probiotic (MP), Yilibao (Bacillus velezensis:Bacillus cereus:Lactobacillus casei = 2:2:1), in Nile tilapia, Oreochromis niloticus. In terms of aerobic Bacillus spp. counts, we produced five diets containing 0, 0.34, 1.68, 3.36 and 6.72 g/kg of MP dry product (Control, T1, T2, T3, T4). Seven hundred and fifty tilapia juveniles (13.26 ± 0.01 g) distributed into 25 tanks in five replications were fed their diet for eight weeks. Results showed that fish fed T3 and T4 diets displayed significantly higher final body weight and weight gain (p < .05). Further, all MP‐treated fish exhibited remarkably decreased plasma lipid profiles (cholesterol, triglycerides) (p < .05) and fish fed T3 and T4 diets displayed significantly higher plasma myeloperoxidase activity and complement C3 content (p < .05). Additionally, fish fed T3 and T4 diets exhibited significantly promoted total antioxidant capacity, glutathione peroxidase activity, glutathione level and declined malondialdehyde content in the plasma and/or liver (p < .05). Moreover, significantly elevated chymotrypsin activity, villus height and intraepithelial lymphocytes counts were found in fish fed T3 and T4 diets (p < .05). As fish fed T3 and T4 diets surpassed the other treatments in growth, immune–antioxidative status and gut health, the recommended dose for tilapia is 3.36–6.72 g/kg.  相似文献   
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Background: This study addresses the antitumoral properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil. Methods: Ethyl Acetate Extracellular Extract (EAE) was used. The metabolites were studied using direct infusion mass spectrometry. The solid Ehrlich tumor model was used for antitumor activity. Female Swiss mice were divided into groups (n = 10/group) as follows: The negative control (CTL−), treated with a phosphate buffered solution; the positive control (CTL+), treated with cyclophosphamide (25 mg/kg); extract treatments at doses of 4, 20, and 100 mg/kg; animals without tumors or treatments (Sham); and animals without tumors treated with an intermediate dose (EAE20). All treatments were performed intraperitoneally, daily, for 15 days. Subsequently, the animals were euthanized, and the tumor, lymphoid organs, and serum were used for immunological, histological, and biochemical parameter evaluations. Results: The extract was rich in meroterpenoids. All doses significantly reduced tumor size, and the 20 and 100 mg/kg doses reduced tumor-associated inflammation and tumor necrosis. The extract also reduced the cellular infiltration of lymphoid organs and circulating TNF-α levels. The extract did not induce weight loss or renal and hepatic toxic changes. Conclusions: These results indicate that P. purpurogenum exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a valid biotechnological approach to the production of antitumor agents.  相似文献   
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