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1.
Mastomys natalensis pretreated with diethylcarbamazine (DEC), levamisole or centperazine were exposed to the standard inoculum of infective larvae of Brugia malayi. Percentage 'take' of infection, duration of prepatent period, course of microfilaraemia and number of adult worms recovered were compared with those of untreated infected Mastomys (control). DEC and centperazine did not alter the 'take' (DEC/centperazine: 100%; control: 88.24%) and the average prepatent period (DEC: 105.44 days; centperazine: 105.18 days, control: 109.20 days). In levamisole pretreated animals on the other hand, the 'take' was much lower (68.18%) with extended prepatent period (125.87 days). However, unlike centperazine and control, the course of microfilaraemia was identical in DEC and levamisole pretreated animals. The average adult worm recovery was significantly high in centperazine pretreated animals being 14.09 as against 8.12, 7.46 and 8.42 in DEC, levamisole pretreated and control animals, respectively.  相似文献   
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The chemotherapeutic efficacy of mebendazole given in combination with Freund's complete adjuvant (FCA) against Brugia malayi in multimammate rat was evaluated. Animals treated with mebendazole, orally at 200 mg/kg x 5 consecutive days along with FCA given subcutaneously (s.c.) on day -10, day 0 and day +15 of the drug treatment killed 48.51% of the adult worms. This drug given alone at the same regimen and by the same route showed only 18.7% mortality rate on adults. Mebendazole given intraperitoneally along with FCA given s.c., however, was four times more efficacious as filaricide than mebendazole alone. Nevertheless, the animals receiving FCA alone also revealed 23.5% mortality rate of adult worms. The animals receiving a combination therapy or FCA alone showed significant increase in antibody titre to the filariae which however decreased in the later stages. No enhancement of antibody level could be detected in animals treated with mebendazole alone. The non-specific immunopotentiation induced by FCA appeared to play a major role in enhancing the activity of mebendazole.  相似文献   
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Data on six lunar crystalline rocks give an apparent Rb-Sr isochron age of 4.42 +/- 0.24 x 10(9) years (95 percent confidence limits) and initial (87)Sr/(86)Sr ratio similar to that in a basaltic achondrite. Relationships between K, Rb, Sr, and Ba and depletion of Eu in these samples point to plagioclase separation from the melts that produced these rocks. The abundance of (157)Gd in the three lunar samples is similar to terrestrial abundance within < 0.2 percent, thus setting a limit of < 6 x 10(15) neutrons per square centimeter for the integrated thermal neutron flux difference between lunar and terrestrial materials.  相似文献   
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Vermicomposting of fly ash has been attempted, using red earthworm, Eisenia foetida. Fly ash, which was obtained from thermal power station, was mixed with cowdung in different proportions (20, 40, 60 and 80%). These mixtures were used as feed for earthworms, and after 30 days, vermicast recovery, worm zoomass and numbers of juveniles produced were recorded. A total of six runs each of 30 days were conducted during the whole study. Concentrations of heavy metals in different mixtures of fly ash–cowdung, before and after vermicomposting and in the earthworms used in the study were also estimated. Results show maximum output of vermicasts and maximum number of juveniles produced was in reactors with 40% fly ash while maximum weight gain by earthworm was in 20% fly ash vermireactors. Performance of vermireactors up to 60% fly ash was more or less similar but at 80% fly ash, there is a marked reduction in overall performance of the reactors. Chemical analysis of different samples of fly ash–cowdung mixtures prior to vermicomposting revealed high concentrations of zinc, chromium, lead, nickel and copper. Chemical analysis of vermicomposted samples showed 30–50% reduction in heavy metals up to 60% fly ash and 10–30% reduction in 80% fly ash. Metal analysis of earthworms revealed considerable bioaccumulation of heavy metals in their body. The Present study indicates the feasibility of E. foetida for mitigating the toxicity of metals and up to 60% fly ash–cowdung mixtures can be used for sustainable and efficient vermicomposting.  相似文献   
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Kappaphycus alvarezzi, an edible seaweed from the west coast of India, was analyzed for its chemical composition. It was found that K. alvarezzi is rich in protein (16.24% w/w) and contains a high amount of fiber (29.40% w/w) and carbohydrates (27.4% w/w). K. alvarezzi showed vitamin A activity of 865 mug retinal equivalents/100 g of sample. It contained a higher quantity of unsaturated fatty acids (44.50% of the total), in which relative percentage of oleic acid was 11%, cis-heptadecanoic acid 13.50%, and linoleic acid 2.3% and 37.0% of saturated fatty acids (mainly heptadecanoic acid). K. alvarezziwas also found to be good source of minerals, viz 0.16% of calcium, 0.033% of iron, and 0.016% of zinc, which are essential for various vital biological activities. Bioavailability of iron by in vitro methods showed a higher efficiency in intestinal conditions than in stomach conditions. Ascorbic acid influenced higher bioavailability of iron. Successive extracts of n-hexane, acetone, ethyl acetate, ethanol, and direct extractables of chloroform/methanol (1:1 and 2:1) were screened for antioxidant activity using a beta-carotene linoleic acid model system (B-CLAMS), DPPH (alpha,alpha-diphenyl-beta-picrylhydrazyl) model system and hydroxyl radical scavenging activity. The chloroform/methanol (2:1) extract has shown 82.5% scavenging activity at 1000 ppm. Acetone fraction extracts at the 1000 ppm level showed 63.31% antioxidant activity in beta-carotene linoleic acid system. The acetone extract showed 46.04% scavenging activity at 1000 ppm concentration. In the case of hydroxyl radical scavenging activity, all the extracts showed better activity at the concentrations of 25 and 50 ppm, where at the 50 ppm level ethyl acetate extract showed 76.0%, acetone 75.12%, and hexane 71.15% activity, respectively. Results of this study suggest the utility of K. alvarezzi (Eucheuma) for various nutritional products, including antioxidant for use as health food or nutraceutical supplement.  相似文献   
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Measurement of total leaf area per plant in crop improvement programmes for a variety of purposes is often very tedious and time consuming. In this paper, we offer a rapid and non-destructive method of estimating the total leaf area in sunflower at the time of anthesis. We show that multiplying the leaf area of a specific leaf position from the apex by the total number of leaves per plant yields total leaf area with more than 95 % accuracy. The specific leaf position for any given genotype in sunflower can be arrived at by multiplying the total number of leaves per plant by the factor 0.355 and rounding off to the nearest highest integer. This technique can be used for the rapid estimation of leaf area per plant at anthesis for any given genotype of sunflower.  相似文献   
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Carrageenans (CGN), sulphated polygalactans, have been reported to be cytotoxic for macrophages in vitro. On this basis, the effect of the 3 major CGN types on humoral immune responses in chickens was investigated. Carrageenan had no effect on body and lymphoid organ weights. Histologically, CGN produced a significant proliferation of reticuloendothelial cells in liver and spleen, but no changes were observed in lymphocyte populations of the bursa of Fabricius, thymus, or spleen. Intracoelomic pretreatment with high doses of CGN induced a marked suppression of primary responses to sheep red blood cells (SRBC) given by the same route. However, if SRBC were injected intravenously into chickens already treated intracoelomically with CGN, no evidence of suppression was demonstrated. Antibody responses to Brucella abortus (BA), a T-independent antigen, were not affected by intracoelomic treatment with CGN. Intravenous pretreatment with CGN did not alter antibody responses to SRBC and BA given by the same route.  相似文献   
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