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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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By the method of minimization of phospholipid bilayers free energy it was shown that at a decrease of inclination angle of dipole fragments of phospholipid molecules to the bilayer surface there take place: a) an increase of bilayer density, b) a decrease of bilayer thickness caused by a decrease of dipole repulsive forces, c) an increase of the number of molecules in the bilayer due to hydrophobization of the latter. The existence of upper and lower critical angles of dipoles inclination to the bilayer surface were found: theta upcrit, theta lowcrit, if theta greater than or equal to the layers must be destroyed, and if theta less than or equal to theta lowcrit, transition of bilayers to the crystalline state must take place.  相似文献   
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"Intracellular" metalloproteinase was purified to homogeneity from Bacillus subtilis 103 crude cell extract, using affinity chromatography on bacitracin-Sepharose 4B. The degree of purification and the yield of the enzyme were about 260-fold and 3%, respectively. In its physico-chemical properties and the amino acid composition the enzyme is very similar, if not identical, to the extracellular metalloproteinase isolated from the culture filtrate of the same strain. Extracellular metalloproteinase-deficient mutant strain Bacillus subtilis SMY-512 does not produce the "intracellular" enzyme either. THe activity of "intracellular" metalloproteinase in the periplasmic space of the cells is about 70% of that in the cytoplasm, thus being indicative of a rather regular distribution of the enzyme throughout the cell compartment.  相似文献   
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Described in the paper are characteristics of B. cepacia clinical strains isolated from patients at Moscow hospitals. The strains were investigated for the presence of proteolytic, chitinolytic, hemolytic and lipase activities as well as for presence of components of the "Quorum sensing" gene activity regulatory system by using biological test-systems and in the polymerase chain reaction with primers to genes cepI and cepR.  相似文献   
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Biofilm formation was studied in 54 strains of Burkholderia cepacia complex isolated in 7 Moscow hospitals. 80% of strains (biofilm groups I and II) had the capacity to biofilm formation and only 16.7% of strains (group III) were not capable to biofilm formation. Molecular genetic methods allowed to identify one of the epidemic markers (CBL, IS hybrid sequence, Burkholderia Cepacia Epidemic Strain Marker - BCESM) in 46.7, 23.3, and 33.3% of strains from group I, II, and III respectively. Gene cepR from the Quorum Sensing system was identified in three biofilm groups in nearly equal frequency (92.3, 96.2 and 100% for group I, II, and III respectively), whereas cepl gene was found more often in group I (76.9%) and II (65.4%). Strains from all three groups had protease and lipase activity and 13.3% of group I strains had chitinolytic activity. B. cepacia strains from group I produced hemolysin in 33.3% of cases, from group II--in 26.6%, and from group III--in 11.1% of cases. The majority of Moscow hospital strains of B. cepacia complex were identified as B. cenocepacia (genomovar III, group A). RAPD-PCR method enabled to differentiate isolated strains into several genotypic variants. 13.3% of strains from group I were susceptible to imipenem/ciprofloxacin, as well as 33.3% of isolates from group II and 44.4% of isolates from group III.  相似文献   
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The analysis of the intestinal microflora in 2,378 patients of different age revealed changes in the state of enteric microflora in all examined patients. In the maximum percent of cases a decrease in the amount of bifidobacteria was observed in children of up to 1 month old and in the amount of lactobacilli, in children aged 6 - 14 years. In patients of all age groups the representatives of such facultative microflora as Staphylococcus aureus or fungi of the genus Candida dominated. The highest proportion of isolated staphylococci was characteristic of children in the first year of life. In the highest percent of cases a decrease in the amount of Escherichia coli with typical properties was observed in persons over 65 years old. Other enterobacteria were most often isolated from adults aged 56 - 65, but the percentage of their isolation was 1.5 times lower than that of Candida. The conclusion was made that the treatment of patients with quantitative and qualitative disturbances of normal enteric microflora needed individual approach in each concrete case with due regard to the patient's age.  相似文献   
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The results of the study of hospital strains of the B. cepacia complex, isolated in hospitals of Moscow, with the use of phenotypical and molecular-genetic methods are presented. The phenotypical methods made it possible to differentiate Russian strains and classify them with a group of genomovars (I, III, IV). As the result the epidemic importance of the strains with epidemic markers, having specific characteristics for every clinic, was determined. The detection of the collection of genes cepI and cepR in the strains made confirmed the epidemic importance of the stains which had, due to the regulatory "quorum sensing" (QS) system, the potential capacity for inducing infection and persisting in the patient's body. The presence of gene cepR in all strains and the absence of gene cepl in 33% of strains gave evidence to suggest that in some strains the activation of the production of pathogenicity factors required the presence of other bacteria having the fully developed QS system. Thus, the new complex approach with the use of phenotypical and molecular-genetic methods permits more precise identification of the source of hospital infection induced by the bacteria of the B. cepacia complex.  相似文献   
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