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排序方式: 共有3849条查询结果,搜索用时 15 毫秒
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Delia V?rg? Petru Lucian Cur?eu Lauren?iu Maricu?oiu Florin A. Sava Irina Macsinga Silvia M?gurean 《PloS one》2014,9(11)
This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members'' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models. 相似文献
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Olga A. Grishina Irina V. Kirillova Olga E. Glukhova 《Computer methods in biomechanics and biomedical engineering》2016,19(3):297-305
The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery. 相似文献
5.
T A Dodatko E A Kiprianova A D Garagulia V V Smirnov 《Antibiotiki i khimioterapii͡a》1988,33(12):901-902
Some methods providing rapid and methodically simple study of large microbial collections and detection of cultures producing bacteriocin-like substances perspective for further investigation are described. The use of cellophane disks and study of the proteolytic enzyme effects allowed the authors to detect organisms producing high molecular antibiotics of protein nature. 相似文献
6.
The physiological role of pyocyanine for Pseudomonas aeruginosa was studied. Its synthesis was shown to commence at the retardation growth phase. Pyocyanine was accumulated only in the growth medium. The addition of 2,6-dichlorophenolindophenol accepting the reducing equivalents from coenzyme Q and transferring them to cytochrome c inhibited the pigment accumulation. This was indicative of the connection between pyocyanine synthesis and the level of the reducing equivalents in the cells. Pyocyanine did not accept the reducing equivalents from coenzyme Q in the respiratory chain of P. aeruginosa. Only reduced pyridine nucleotides served as substrates for pyocyanine in the reaction of autooxidation. The kinetic parameters of this reaction and the affinity of NADH dehydrogenase for the substrate were measured. The kinetic data were analysed to show that, under the physiological conditions, pyocyanine could not apparently compete with the respiratory chain for the reducing equivalents and hence directly regulate the level of NAD(P)H in P. aeruginosa cells. In order to keep the oxidising activity at a level necessary for the cells, the latter decreased the content of the reducing equivalents either by synthesizing pyocyanine or owing to the activity of cyanide-resistant oxidase. These processes of releasing the reducing equivalents are in a reciprocal relationship. 相似文献
7.
Vyacheslav L. L'vov Irina K. Verner Larisa Yu. Musina Alexander V. Rodionov Anatoly V. Ignatenko Alexander S. Shashkov 《Archives of microbiology》1992,157(2):131-134
On the basis of chemical and NMR data the partial structure of lipid A from lipooligosaccharide (LOS) of Neisseria meningitidis group B, strain BC5S No 125 was established. Lipid A consisted of disaccharide 2-deoxy-6-O-[2-deoxy-2-(3-hydroxytetradecanoylamino)--gluco-pyranosyl]-2-(3-hydroxytetradecanoylamino)--glucopyranose carrying the -(2-aminoethyl)pyrophosphate residue at 0–4 and the pyrophosphate or phosphate residue at 0–1. On hydrolysis of the acidic form of LOS with 1% acetic acid the substituent at 0–1 was practically completely removed whereas that at 0–4 was stable. The analogous hydrolysis of the Mg-salt of LOS was accompanied by splitting off the pyrophosphate linkage in the substituent at 0–4. Hydrolysis of LOS at pH 4.5 in the presence of SDS led mainly to a lipid A preparation retaining both pyrophosphate residues.Abbreviations KDO
2-keto-3-deoxyoctulosonic acid
- LA-I, LA-II
preparations of lipid A
- LOS
lipooligosaccharide
- LOS-H+
the acidic form of LOS
- OS
oligosaccharide
- TLC
thin-layer chromatography
- GLC-MS
gas-liquid chromatography/mass spectrometry 相似文献
8.
Violeta Datcheva Aleksei Kamernitskii Radoslav Vlahov Natalia Voishvillo Vera Levi Irina Reshetova Elena Chernoburova 《Applied microbiology and biotechnology》1986,25(1):14-17
Summary A high-yield microbiological transformation of polyfunctional 5-3-acetoxy steroids, containing an additional ring E, by Corynebacterium mediolanum strain B-964 was carried out, resulting in the corresponding 4-3-ketones. It was shown that the type of transformation and the yield of the reaction depend on the degree of saturation of the ring E and on the position of the oxygen-containing substituents in it. 相似文献
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Igor Ya. Belyaev Irina M. Spivak Ada Kolman Mats Harms-Ringdahl 《Mutation research》1996,358(2):735-230
Chromatin conformation changes in the normal human fibroblasts VH-10 were studied by the method of anomalous viscosity time dependence (AVTD). Gamma-irradiation of cells in a dose range of 0.1–3 Gy caused an increase in maximal viscosity of cell lysates. Conversely, irradiation of cells with low doses of 0.5 or 2 cGy resulted in a decrease in the AVTD peaks with a maximum effect approximately 40 min after irradiation. The same exposure conditions were used to study a possible adaptive effect of low doses, measured by changes in cell survival. A primary dose of 2 cGy caused significant modification of cell response to a challenge dose. Approximately 20% protection to challenge doses of 0.5 Gy (p < 0.003), 2 Gy (p < 0.02) and 2.5 Gy (p < 0.002) was observed. However, the direction of this effect (adaptation or synergism) was found to be dependent on a challenge dose. The combined effect of 2 cGy and 1 Gy was significantly synergistic, while no modification was observed for 1.5 Gy and 3 Gy. A partial correlation was found between the AVTD changes and cell survival when the combined effect of a primary dose of 2 cGy and challenge dose was examined. The dose of 2 cGy alone increased survival by 16% (p < 0.0003). These results suggest that the low-dose induced effects on survival may be related to chromatin reorganization. 相似文献