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1.
The study of the specific epidemiological and clinical features of Q fever revealed the existence of an active focus of infection among humans due to their contacts with agricultural animals in one of the districts of the region. The focus was manifested by group morbidity among the cattle-tending personnel of a dairy farm. The source of this infection was cattle. The infection was transferred mainly through the air. The disease took a moderately severe course. The study of the rickettsial contamination of humans, animals and ticks suggested the presence of the active epidemic process and made it possible to work out concrete antiepidemic measures.  相似文献   
2.
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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4.
Tick-borne encephalitis virus (TBEV) is transmitted to vertebrates by taiga or forest ticks through bites, inducing disease of variable severity. The reasons underlying these differences in the severity of the disease are unknown. In order to identify genetic factors affecting the pathogenicity of virus strains, we have sequenced and compared the complete genomes of 34 Far-Eastern subtype (FE) TBEV strains isolated from patients with different disease severity (Primorye, the Russian Far East). We analyzed the complete genomes of 11 human pathogenic strains isolated from the brains of dead patients with the encephalitic form of the disease (Efd), 4 strains from the blood of patients with the febrile form of TBE (Ffd), and 19 strains from patients with the subclinical form of TBE (Sfd). On the phylogenetic tree, pathogenic Efd strains formed two clusters containing the prototype strains, Senzhang and Sofjin, respectively. Sfd strains formed a third separate cluster, including the Oshima strain. The strains that caused the febrile form of the disease did not form a separate cluster. In the viral proteins, we found 198 positions with at least one amino acid residue substitution, of which only 17 amino acid residue substitutions were correlated with the variable pathogenicity of these strains in humans and they authentically differed between the groups. We considered the role of each amino acid substitution and assumed that the deletion of 111 amino acids in the capsid protein in combination with the amino acid substitutions R16K and S45F in the NS3 protease may affect the budding process of viral particles. These changes may be the major reason for the diminished pathogenicity of TBEV strains. We recommend Sfd strains for testing as attenuation vaccine candidates.  相似文献   
5.
A new amino sugar named eremosamine was isolated from hydrolysate of eremomycin, an antibiotic belonging to the group of polycyclic glycopeptides. Crystalline derivatives of the amino sugar i. e. methyleremosaminide and methyl-N,O-acetyleremosaminide (alpha- and beta-anomers) were prepared. The data on PMR study and optic properties of the compounds showed that eremosamine had the structure of 2,3,6-tridesoxy-3-amino-3-C-methyl-L-arabinohexose.  相似文献   
6.
Strain 344 synthesizing an antibiotic complex was isolated after fusion of the protoplasts of Streptomyces monomycini producing monomycin and Streptomyces kanamyceticus producing kanamycin. The major component of the complex was identified with albofungin and the minor one was suggested to be chloralbofungin. In the cultures of strain 344 variants forming monomycin were detected. After regeneration of the protoplasts of the parent strains there were isolated no stable clones synthesizing antibiotics differing from monomycin and kanamycin.  相似文献   
7.
Carminomycins II and III, the main components of the carminomycin complex were isolated in pure state. Their crystalline exalates and acetate of cardminomycin II were prepared. The PMR spectra of both carminomycins and the 13C-NMR spectra of the oxalates were obtained. The molecular weights of the antibiotics were determined by mass-spectrometry. On the basis of the PMR spectra it was shown that carminomycins II and III had similar structures and differed in the stereoisomerism of the nitrogen-free fragment linked to the amino sugar. This was confirmed by the 13C-NMR spectra. The above fragment (C7H15O3) is analogous to the fragment of baumycins A1 and A2 described earlier.  相似文献   
8.
The composition of virenomycin, a new antitumor antibiotic was studied. Two components V and M were detected with high resolution liquid chromatography and thin layer chromatography on siluphol (Czechoslovakia) and silica gel (Merk, BRD). A preparative method for separation of the antibiotic components with the use of chromatography on columns with silica gel was developed. Biological and physicochemical properties of separate components were studied to show that they significantly differed by their antibacterial action in vitro: virenomycin V was 2 to 4 times more active than virenomycin M against a number of microbes. The physicochemical properties of the components are similar. It was shown with mass spectrometry that the molecular weight of virenomycin is 12 units higher than that of virenomycin M. The PMR spectra showed that this difference is due to the presence of a vinyl group in the chromophore moiety of the virenomycin V molecule and a methyl group at the similar site of the virenomycin M molecule.  相似文献   
9.
An attempt at demonstrating lateral power transmission over millimeter distances along a coupling membrane has been undertaken. Trichomes of the multicellular filamentous cyanobacteria Phormidium uncinatum were illuminated with a very narrow light beam forming a light spot that covered only 4–5% of a 1–2 mm long cyanobacterial trichome. Such illumination was found to support motility (gliding along agar surface) of the trichome under conditions when the light was the only energy source. It was also shown that illumination with the light spot caused rotation of rings of slime (accompanying the operation of the ‘motors’ responsible for the motility of cyanobacteria) not only in the illuminated, but also in the distal, nonilluminated part of the trichome. Electric potential transmission along trichomes was revealed by means of the extracellular electrode technique. The light spot was found to induce generation of an electric potential difference between two electrodes in the dark region of the trichomes, which were placed at different distances from the illuminated end. Cutting the trichomes between the light spot and the closest ‘dark’ electrode abolished this effect. Valinomycin + K+ and carbonyl cyanide p-trifluoromethoxyphenylhydrazone affected the potential difference formation between two ‘dark’ electrodes much stronger than that between a light and a dark electrode. All the light spot-induced effects develop in the seconds time scale. Both the amplitudes and the kinetics of the potential difference measured with four electrodes placed along the trichome prove to be in good agreement with the theoretical curves computed on the basis of the electric cable equation. It is concluded that transcellular power transmission in the form of Δψ takes place along trichomes of cyanobacteria. This confirms the hypothesis about the biological function of Δψ as a transportable form of energy.  相似文献   
10.
The structures of ristomycin and actinoidine amino acids described earlier were revised. Crystalline derivatives of the amino acids and the products of their oxidation were prepared. The study on the spectral properties of the compounds showed that ristomycin and actinoidine amino acids had the structures of 3-(2'-hydroxy-5'-glycyl-phenoxy)-4-methyl-5-hydroxyphenylglycine and 2-(2'-hydroxy-5'-glycyl-phenyl)-3,5-dioxyphenylglycine respectively. They did not differ from deaminodicarboxylic acids prepared with ristocetin, vancomycin and actionoidine.  相似文献   
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