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111.
Filarial parasites, Litomosoides carinii and Setaria cervi, showed great susceptibility to the oxidants generated in vitro by the xanthine/xanthine-oxidase system. In order to counteract such injurious effects, both the filariids possessed an active antioxidant enzymes system. Superoxide dismutase, catalase and glutathione peroxidase were detected in appreciable amounts but glutathione reductase and glucose-6-phosphate dehydrogenase in very low quantities. The former three enzymes were also found to be released by the parasites into the ambient medium. The released enzymes may be responsible for scavenging the host-generated oxidants present in the immediate surroundings of the parasites and thereby enabling them to live comfortably in the host. This Institute-based antifilarial agent namely Compound 82/437 which is 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolylketone, markedly inhibited catalase and glutathione peroxidase of both L. carinii and S. cervi. The compound, therefore, appears to render the filariids prone to H2O2 toxicity leading to penultimate damage.  相似文献   
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Leptospira, a member of the order Spirochaetales, is the causative agent of leptospirosis, an important zoonosis encountered worldwide. The Leptospira interrogans serovar Sejroe was grown in EMJH medium and its DNA was isolated using standard techniques. The LipL32 gene was amplified using the reported primer of Kirschneri of LipL32. The amplified product was found to comprise 756 base pairs. This amplified gene fragment of LipL32 lipoprotein was cloned in E. coli (DH5α) cells using pDrive plasmid as a vector. The recombinant cells were selected on LB agar medium containing ampicillin, X-gal and isopropyl-β-d-thiogalactopyranoside. Plasmid was extracted from the recombinant white colonies, and restriction endonuclease (RE) analysis was carried out using PstI and SalI. On partial sequence analysis, the product exhibited 756 base pairs, corresponding to 251 amino acids. The cloned gene could be further used for expression of recombinant protein for serodiagnosis of leptospirosis.  相似文献   
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Summary The water status and nitrogen metabolism of the groundnut (Arachis hypogaea L.) cultivars, M-13 and M-145 were examined during a period of water stress and recovery. 10 day old seedlings, grown in controlled environment were exposed to solutions of polyethylene glycol (MW 6000, osmotic potential, –0.5 or –0.8 MPa = –5 or –8 bars) for a week when the stress was relieved by replacing the PEG solution with a nutrient solution. Relative turgidity, total protein and free amino acid concentration and nitrate reductase activity were measured during the period of stress and recovery. Cultivar M-13, despite its lower relative turgidity during stress, was better able to preserve its protein concentration and nitrate reductase activity, and recover to a normal state within three days of the relief of stress. M-145, on the other hand, failed to recover within this period. The results are discussed in the light of the known performance of the two cultivars in the field under drought conditions.  相似文献   
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Seed Protein Concentrates (SPC) of 6 species ofCrotalaria were extracted and the extractabilities of SPC, total N and protein N determined. SPC of high yielding species (C. juncea) was analysed for the contents of amino acids, ash, phosphorus, sugar, starch, fibre and calories, as well as forin vitro digestibility. Results indicate the promising potential ofC. juncea for SPC yield.  相似文献   
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European Journal of Plant Pathology - Symptoms of bunchy top, little leaf, leaf chlorosis with chlorotic streaks, leaf necrosis and stunted growth were noticed in two banana cultivars, Champa and...  相似文献   
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Use of literature crop coefficient (K c) values for quantifying evapotranspiration (ETc) under non-standard conditions such as plastic mulch, shallow water table, and sub-tropical conditions can lead to inaccurate ETc estimates. A 5-year experiment was conducted for fall crop growing seasons in south Florida to quantity bi-weekly ETc and K c for bell pepper grown under shallow water table and plastic mulch environments using large drainage lysimeters. The ETc values varied from 205 to 320 mm with a seasonal average of 267 mm. Average K c values for bell pepper for development, mid-season, and late stages were 1.05, 1.21, and 1.28, respectively. Higher than literature initial K c values were due to rainfall and use of sub-irrigation system to maintain artificially high water table which results in high soil moisture in the bare soil area—such high moisture results in high evaporation. The K c values from this study were statistically higher than literature values. Use of literature K c values resulted in underestimating ETc by 27–37%. The K c values would provide improved estimates of sub-irrigated pepper ETc in subtropical Florida and elsewhere with similar environment.  相似文献   
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