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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed.  相似文献   
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Summary The title compound was prepared by a three-stage enzymatic procedure consisting of (i) RNA hydrolysis to a mixture of ribonucleosides using intact mycelium of Spicaria violacea, (ii) transribosylation of exogenous adenine employing whole cells of Escherichia coli as a biocatalyst, and (iii) conversion of formed adenosine into ATP by the enzymes of alcohol fermentation and the kinases extracted from baker's yeast.  相似文献   
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Summary The title compound was prepared by a two step enzymatic procedure consisting of DNA hydrolysis to the mixture of 2-deoxynucleosides followed by a transdeoxyribosilation of exogenous adenine.  相似文献   
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Summary Substrate activity of 1- and 3-deazapurines in the reaction of microbiological ribo- 2-deoxyribosylation catalysed by purine nucleoside phosphorylase of viable cells ofE. coli BMT-1D/1A has been studied. Guanosine or 2-deoxyguanosine were used as donors. 1-Deazapurines are good substrates in both reactions; 3-deazapurines are very effective intransdeoxyribosylation but not intransribosylation. Benzimidazole is an excellent substrate in both reactions indicating that N(1) and N(3) are not essential for transglycosylation.  相似文献   
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Abstract

Reaction of 02,3′-anhydro-5′-0-trityl-2′-deoxycytidine (1) with LiN3s in DMF resulted in the formation of 1-(3-azido-2,3-dideoxy-5-0-trityl-β-D-erythro-pentofuranosyl) cytosine (2) and 3-0-(4-amino-1,3-pyrimidin-2-yl)-5-0-trityl-2-deoxy-α-D-threo-pentofuranosyl azide (3) (2:3 = 1:1) in 88% yield. Compound 3 was deprotected with 80% aqueous AcOH yielding 4  相似文献   
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9-(3-Deoxy-beta-D-erythro-pentofuranosyl)-2,6-diaminopurine (2) was synthesized by an enzymatic transglycosylation of 2,6-diaminopurine using 3'-deoxycytidine (1) as a donor of the sugar moiety. Nucleoside 2 was transformed to 3'-deoxy guanosine (3), 9-(3-deoxy-beta-D-erythro-pentofuranosyl)-2-amino-6-oxopurine (3'-deoxyisoguanosine; 4), and 9-(3-deoxy-beta-D-erythro-pentofuranosyl)-2-fluoroadenine (5). Compounds 2-5 were evaluated for their anti-HIV activity.  相似文献   
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We studied the effect of an epoxy derivative of dephosphorylated 2′,5′-trioligoadenylate (5′,5′ApApAepoxy) resistive to the action of cellular phosphodiesterase on cells of human neuroblastoma IMR 32 cultured in vitro. Twenty-two hours after the addition of 5·10−6 M 2′,5′ApApAepoxy to the culture medium, the number of cells decreased by 20% (P < 0.05), while the content of protein in these cells increased, on average, by 52% (P < 0.01), as compared with the control. The activities of Na+,K+-and Ca2+, Mg2+-ATPases in a microsomal fraction obtained from cells cultured in the presence of 2′, 5′ ApApAepoxy decreased by 50% (P < 0.001) as compared with those in the control cells. Our data indicate that 2′,5′ApApAepoxy possess antiproliferative activity. According to our findings, the antiproliferative effect of 2′,5′ ApApAepoxy can, to a great extent, be explained by the fact that this oligoadenylate derivative significantly modulates the activities of Na+,K+-and Ca2+,Mg2+-ATPases. Neirofiziologiya/Neurophysiology, Vol. 38, No. 2, pp. 97–102, March–April, 2006.  相似文献   
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