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51.
On the basis of expert knowledge, an expert model of potential performance covering the motor, morphological, psychological, and sociological subspace was constructed (MMPS). The scores of variables were obtained by application of the computer program Sport Measurement Management System (SMMS). In the subjects included in measurements, trends of the obtained average scores of variables were established through various competition categories and age periods. The sample of subjects consisted of 48 cross-country skiers in three competition categories. Fluctuations in development in individual age periods are larger in the motor and morphological subspace. In the psychological subspace, an upward trend of average scores can be noticed, while the sociological subspace is not subjected to any essential changes in different age and competition categories. Monitoring of cross-country skiers across all three competition categories showed that in these age categories there are periods which owing to laws of development do not allow uniform progress. Therefore, the principle of individuality must be taken into account especially in planning the transformation process. 相似文献
52.
Tatjana Mihajilov-Krstev Dragan Radnović Dušanka Kitić Bojan Zlatković Mihailo Ristić Suzana Branković 《Central European Journal of Biology》2009,4(3):411-416
Essential oil of Satureja hortensis L. was analyzed by GC and GC/MS and tested by a broth micro-well dilution method for activity against multiresistant clinical
isolates of pathogenic bacteria from 10 different genera: Klebsiella, Escherichia, Proteus, Staphylococcus, Streptococcus, Pseudomonas, Enterococcus, Enterobacter, Citrobacter and Acinetobacter. The main compounds in the oil were carvacrol (67%), γ-terpinene (15.3%) and p-cymene (6.73%). The oil showed activity against
all tested strains. MIC/MBC values were in the range of 0.78-25 μl/ml, with the exception of the strain P. aeruginosa. Microbicidal
concentration for this particular strain (50 μl/ml) was the highest tested concentration. The oil showed inhibitory and bactericidal
effect at the same concentration (MIC=MBC) for all but three strains. 相似文献
53.
54.
All physico-chemical parameters that affect bacterial growth rate will also affect bacterial molecular composition, which
in turn influences the chemical composition of bacterial lysate and its turnover rate in the ecosystem. To produce qualitatively
different lysates, Vibrio sp. cells were grown under different pH, salt, or temperature conditions in rich growth media and then washed and lysed by
autoclaving. Both the absolute concentrations and the ratios between elements in the lysates varied with different growth
conditions, implying differences in lysate quality. Either Pseudoalteromonas sp. or Vibrio sp. was grown on the lysates at non-limiting lysate concentrations. Different lysates supported growth rates of Pseudoalteromonas sp. in the range from 0.25 to 1.53 h−1. On the other hand, growth rates of Vibrio sp. grown on its own lysates were around 0.4 h−1 and were not dependent on lysate quality. Two orders of magnitude decrease in Zn concentration in Vibrio sp. cells grown on different lysates as compared to cells grown on rich growth medium suggested that Zn might be a factor
limiting growth. In the simple microbial loop studied, the initial difference in lysate quality was preserved in Pseudoalteromonas sp., whereas Vibrio sp. decreased the initial differences in lysate quality, thereby neutralizing the primary effect of environmental conditions
on carbon turnover. 相似文献
55.
The nature of the unfolded state plays a great role in our understanding of proteins. However, accurately studying the unfolded state with computer simulation is difficult, due to its complexity and the great deal of sampling required. Using a supercluster of over 10,000 processors we have performed close to 800 micros of molecular dynamics simulation in atomistic detail of the folded and unfolded states of three polypeptides from a range of structural classes: the all-alpha villin headpiece molecule, the beta hairpin tryptophan zipper, and a designed alpha-beta zinc finger mimic. A comparison between the folded and the unfolded ensembles reveals that, even though virtually none of the individual members of the unfolded ensemble exhibits native-like features, the mean unfolded structure (averaged over the entire unfolded ensemble) has a native-like geometry. This suggests several novel implications for protein folding and structure prediction as well as new interpretations for experiments which find structure in ensemble-averaged measurements. 相似文献
56.
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58.
Bârzu O Kiss L Bojan O Niac G Mantsch HH 《Biochemical and biophysical research communications》1976,73(4):894-902
The 1,N6-ethenoadenine nucleotide analogs epsilonADP and epsilonATP, contrary to recent findings (1), are shown to be unable to penetrate the inner mitochondrial membrane of intact rat liver mitochondria and can not be used as substrates by the respiratory chain enzymes in oxidative phosphorylation. On the other hand, these analogs are able to participate in transphosphorylation reactions, being good substrates for mitochondrial phosphotransferases located in the intermembrane space, such as nucleosidediphosphate kinase and adenylate kinase. 相似文献
59.
A micromorphological analysis of leaf epidermal tissue of 18 Trifolium species was carried out using light and scanning electron microscopy, in order to obtain qualitative and quantitative data on epidermal characteristics and to evaluate their taxonomic significance. The shape of epidermal cells and their cell walls, epidermal wax depositions, presence of papillae, type and number of stomata, type, distribution and number of non-glandular and glandular trichomes were analyzed. The results showed that species that belong to the same section had some common leaf epidermal characteristics. Combinations of those characters proved to be useful in taxonomy at the level of the sections, but not for identification of single species. 相似文献
60.
Huzjan R Brkljacić B Delić-Brkljacić D Biocina B Sutlić Z 《Collegium antropologicum》2004,28(Z2):235-241
The objective of this paper was to establish the normal findings of B-mode and color Doppler ultrasound of the forearm arteries in candidates for coronary artery bypass grafting with radial artery graft. Examination of radial and ulnar arteries was performed in 127 patients. The vessel diameters and peak systolic velocities were measured and the presence of atherosclerotic changes, calcifications and anatomical variants was assessed. Radial artery proved to be dominant forearm artery with non-significant side-to-side asymmetry. The luminal changes were present in 30% of the patients. Ulnar arteries were more prone to these changes than radial arteries (28.4% vs. 24.4%). The anatomical variants found included ulnar artery hypoplasia in 3.9% of patients and high brachial artery bifurcation in 2.4% of patients. No cases of high-grade stenosis or occlusion were found. The results of the present study indicate that B-mode and color Doppler are valuable methods for preoperative screening as they enable morphological and functional evaluation of the forearm circulation. 相似文献