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81.
Momčilo Mihailović Paul Lindberg Ivan Jovanović Duŝan Antić 《Biological trace element research》1992,33(1-3):71-77
The selenium (Se) contents in common cereals in endemic and nonendemic areas in Serbia are very low. Plasma Se levels of both
patients and healthy subjects, were also low, reflecting low Se intakes. Patients with Balkan endemic nephropathy (BEN) had
significantly lower (p<0.05) plasma Se levels than healthy individuals, both from regions close to endemic areas, and from Belgrade. Mean plasma
Se of BEN patients was slightly but insignificantly higher in samples taken immediately after dialysis than in those taken
before, suggesting that very little of the Se present in plasma is dialyzable. Plasma SeGSH-Px activities before and after
hemodialysis in both BEN and Nonendemic chronic renal failure (NCRF) patients were not significantly different, but BEN patients
had lower enzyme activities than those with NCRF and healthy controls. In BEN patients, a significant correlation between
plasma Se and SeGSH-Px activity was found.
NCFR patients were with diagnoses: TBC of kidneys, chronic glomerulonephritis, chronic pyelonephritis, and polycystic kidneys. 相似文献
82.
Darja Barlič Maganja Borut Štrukelj Jože Pungerčar Franc Gubenšek Vito Turk Igor Kregar 《Plant molecular biology》1992,20(2):311-313
A genomic DNA clone encoding an aspartic proteinase inhibitor of potato was isolated from a lambda EMBL3 phage library using the aspartic proteinase inhibitor cDNA as a hybridization probe. The gene has all characteristic sequences normally found in eucaryotic genes. Typical CAAT and TATA box sequences were found in the 5-upstream region. In this part are also two putative regulatory AGGA box sequences located. In the genomic sequence there are no intron sequences interrupting the coding region. An open reading frame of the gene encodes a precursor protein of 217 amino acids which shows high percent identity with the aspartic proteinase inhibitor cDNA. 相似文献
83.
Biserka Kojić-Prodić Živa Ružić-Toroš Ljubo Golič Branko Brdar Jože Kobe 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1982,698(2):105-110
The crystal and molecular structure of one imidazo[1,2-a]-s-triazine nucleoside and its antiviral activity are described. The crystal structure of 2-amino-8-(β-d-ribofuranosyl)imidazo-[1,2-a]-s-triazin-4-one monohydrate (C10H13N5O5·H2O) was solved by X-ray counter data. The compound crystallizes in the monoclinic space group P21 with cell dimensions a = 7.353 (1), b = 6.465 (1), c = 13.701 (1) Å, β = 104.64 (1)°. The structure was solved by direct methods and refined by full matrix least-squares technique to a final value of the conventional R-factor of 0.049 using 1998 observed intensities. The orientation of the base relative to the sugar ring defined in terms of rotation about the C(1′)-N(8) glycosyl bond is anti (47.8°). The ribose moiety exhibits C(2′)-endo, 2E conformation. The conformation around C(4′)-C(5′) is gauche?. Molecular packing is dominated by hydrogen bonds. Base stacking occurs long the b axis. 5-Aza-7-deazaguanosine has shown a marked antiviral activity in vitro against herpes simplex virus despite the fact that N(3) is effective as the hydrogen acceptor only. 相似文献
84.
S. Pažoutová L. S. Slokoska N. Nikolova T. I. Angelov 《Applied microbiology and biotechnology》1982,16(4):208-211
Summary In submerged cultures of Claviceps sp. CP II, elymoclavine was synthesized only by the growing mycelium (phase P1), whereas cultures of C. purpurea strain 129 produced agroclavine after vegetative growth had also ceased (phase P2). In strain CP II, the peak of activity of malate dehydrogenase, glucose-6-phosphate dehydrogenase and phosphatases was related to the time of maximum growth rate and alkaloid production. Citrate synthase activity paralleled the course of alkaloid synthesis. Strain 129 exhibited a further activity peak of the same magnitude during phase P2. ATP levels in both cultures corresponded to the pattern of change in enzyme activities. Strain CP II contained roughly twice as much orthophosphate and ATP in its cells as strain 129 and exhibited higher average activity of glucose-6-phosphate dehydrogenase. It follows from these results that alkaloid synthesis requires the processes of primary metabolism, even when it occurs after active growth of the culture has ceased. Cultures producing alkaloids oxidized at C-8 exhibit higher glucose-6-phosphate dehydrogenase activity, probably because of a higher NADPH consumption. 相似文献
85.
Penicillium cyclopium growing in a surface culture with 2-ketoglutarate or glutamate as a sole carbon source produced ethylene in two phases. The first peak of ethylene production (EP 1) was associated with aerial mycelium growth whereas the second peak of ethylene production (EP 2) occurred with formation and maturation of conidia. Conidiation was induced by blue light between 120 and 172 h after the culture was started and depended on the presence of a carbon source at the stage of conidiophore initiation. Exogenous phosphate content dropper rapidly before the onset of conidiation. The EP 2 was connected with conidiation via this drop. Addition of phosphate prior to the conidiophore initiation and during conidiation inhibited EP 2 without affecting conidiation, but conidia lacked a green pigment and their germination ability decreased by 905. Exogenous ethylene did not restore normal development. The EP 2 in asporogenic cultures was evoked by incubation in the dark and by phosphate removal. The EP 2 and conidiation were accompanied by an increased oxygen consumption. The EP 1 yield of ethylene depended only on biomass growth and was unaffected by any treatment mentioned above. 相似文献
86.
87.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
88.
Factors affecting the elicitation of sesquiterpenoid phytoalexin accumulation by eicosapentaenoic and arachidonic acids in potato 总被引:5,自引:5,他引:0 下载免费PDF全文
Eicosapentaenoic and arachidonic acids in extracts of Phytophthora infestans mycelium were identified as the most active elicitors of sesquiterpenoid phytoalexin accumulation in potato tuber slices. These fatty acids were found free or esterified in all fractions with elicitor activity including cell wall preparations. Yeast lipase released a major portion of eicosapentaenoic and arachidonic acids from lyophilized mycelium. Concentration response curves comparing the elicitor activity of the polyunsaturated fatty acids to a cell-free sonicate of P. infestans mycelium indicated that the elicitor activity of the sonicated mycelium exceeded that which would be obtained by the amount of eicosapentaenoic and arachidonic acids (free and esterified) present in the mycelium. Upon acid hydrolysis of lyophilized mycelium, elicitor activity was obtained only from the fatty acid fraction. However, the fatty acids accounted for only 21% of the activity of the unhydrolyzed mycelium and the residue did not enhance their activity. Centrifugation of the hydrolysate, obtained from lyophilized mycelium treated with 2n NaOH, 1 molarity NaBH4 at 100°C, yielded a supernatant fraction with little or no elicitor activity. Addition of this material to the fatty acids restored the activity to that which was present in the unhydrolyzed mycelium. The results indicate that the elicitor activity of the unsaturated fatty acids is enhanced by heat and base-stable factors in the mycelium. 相似文献
89.
90.