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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
4.
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.
Alterations in the sialylation and sulfation of secreted mouse thyrotropin in primary hypothyroidism 总被引:1,自引:0,他引:1
G S DeCherney N Gesundheit P W Gyves C R Showalter B D Weintraub 《Biochemical and biophysical research communications》1989,159(2):755-762
We investigated the effect of in vivo hypothyroidism on the sialylation and sulfation of thyroid-stimulating hormone (TSH) secreted by mouse pituitary explants. Oligosaccharides from secreted thyroid-stimulating hormone from hypothyroid animals contained greater sialic acid relative to sulfate in both alpha and beta subunits. Aging per se had little effect on thyroid-stimulating hormone sialylation or sulfation. Variable sialylation and sulfation demonstrates a mechanism for charge microheterogeneity of thyroid-stimulating hormone, and the increasing sialylation observed with hypothyroidism may functionally mediate the prolonged metabolic clearance that has been noted previously. 相似文献
6.
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
7.
Rats treated with ethinylestradiol (5 mg kg-1 day-1 for 5 days) secrete de novo synthesized bile acids at a markedly reduced rate (-57%). Administration of the nonionic detergent Triton WR-1339 to estradiol-treated rats rapidly restored the rate of secretion of de novo synthesized bile acids to control levels. In contrast, when Triton was administered to control rats, the secretion rate of bile acids was unaffected. The reduction in bile acid synthesis displayed by estradiol-treated rats was similar to the 50% decrease in the activity of hepatic microsomal 7 alpha-hydroxylase. The activity of 7 alpha-hydroxylase was also restored to control levels by the administration of Triton to estradiol-treated rats. We examined the possibility that estradiol acts directly on the hepatic microsomes. Adding increasing amounts of estradiol to microsomes obtained from control rats resulted in decreasing activities of 7 alpha-hydroxylase. The inhibition by estradiol of 7 alpha-hydroxylase obtained in vitro occurred with amounts of estradiol that were found to accumulate in the liver via in vivo treatment. Double-reciprocal analysis showed that at and below 50 micrograms of estradiol/0.5 mg of protein uncompetitive inhibition was displayed. Additional experiments showed that adding Triton to microsomes obtained from estradiol-treated rats increased the activity of 7 alpha-hydroxylase to control levels. In contrast, Triton did not increase the activity of 7 alpha-hydroxylase when it was added to control microsomes. These data show for the first time that the estrogenic steroid estradiol acts directly on the microsomes and inhibits both the activity of 7 alpha-hydroxylase and the rate of bile acid synthesis.(ABSTRACT TRUNCATED AT 250 WORDS) 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
9.
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
10.
Tissue-specific expression of two members of the cell wall hydroxyproline-rich glycoprotein (HRGP) family, extensin and potato tuber lectin, was examined by immunolocalization at the light microscope level in various organs (leaves, stems, roots, fruit, tuber) of carrot ( Daucus carota cv. Thumbelina), tomato ( Lycopersicon esclentum cv. Pixie Hybrid II), and potato ( Solanum tuberosum cv. Kennebec). Extensin was prominently expressed in vascular tissue, particularly xylem and also phloem, although virtually all cells displayed some degree of staining which varied as a function of the tissue, organ, and plant under study. Antibodies against potato tuber lectin (PTL) displayed a localization pattern similar to that observed for extensin; notably PTL did not stain cambium but did stain epithelial cells lining secretory cavities. These distribution patterns are consistent with a role for extensin, and possibly PTL, in providing mechanical support in tissues subjected to compression or torsional stress imparted by vascular growth, or by similar stress brought about by transport of vascular fluids. 相似文献