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971.
Household‐level correlates of children's physical activity levels in and across 12 countries
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Deirdre M. Harrington Fiona Gillison Stephanie T. Broyles Jean‐Philippe Chaput Mikael Fogelholm Gang Hu Rebecca Kuriyan Anura Kurpad Allana G. LeBlanc Carol Maher Jose Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Mark S. Tremblay Catrine Tudor‐Locke Pei Zhao Peter T. Katzmarzyk for the ISCOLE Research Group 《Obesity (Silver Spring, Md.)》2016,24(10):2150-2157
972.
The genetic structure of 65 chicken populations was studied using 29 simple sequence repeat loci. Six main clusters which corresponded to geographical origins and histories were identified: Brown Egg Layers; predominantly Broilers; native Chinese breeds or breeds with recent Asian origin; predominantly breeds of European derivation; a small cluster containing populations with no common history and populations that had breeding history with White Leghorn. Another group of populations that shared their genome with several clusters was defined as 'Multi-clusters'. Gallus gallus gallus (Multi-clusters), one of the subspecies of the Red Jungle Fowl, which was previously suggested to be one of the ancestors of the domesticated chicken, has almost no shared loci with European and White Egg layer populations. In a further sub-clustering of the populations, discrimination between all the 65 populations was possible, and relationships between each were suggested. The genetic variation between populations was found to account for about 34% of the total genetic variation, 11% of the variation being between clusters and 23% being between populations within clusters. The suggested clusters may assist in future studies of genetic aspects of the chicken gene pool. 相似文献
973.
Melissa A. Partridge Sumana Gopinath Simon J. Myers Jens R Coorssen 《Journal of chemical biology》2016,9(1):9-18
An initial proteomic analysis of the cuprizone mouse model to characterise the breadth of toxicity by assessing cortex, skeletal muscle, spleen and peripheral blood mononuclear cells. Cuprizone treated vs. control mice for an initial characterisation. Select tissues from each group were pooled, analysed in triplicate using two-dimensional gel electrophoresis (2DE) and deep imaging and altered protein species identified using liquid chromatography tandem mass spectrometry (LC/MS/MS). Forty-three proteins were found to be uniquely detectable or undetectable in the cuprizone treatment group across the tissues analysed. Protein species identified in the cortex may potentially be linked to axonal damage in this model, and those in the spleen and peripheral blood mononuclear cells to the minimal peripheral immune cell infiltration into the central nervous system during cuprizone mediated demyelination. Primary oligodendrocytosis has been observed in type III lesions in multiple sclerosis. However, the underlying mechanisms are poorly understood. Cuprizone treatment results in oligodendrocyte apoptosis and secondary demyelination. This initial analysis identified proteins likely related to axonal damage; these may link primary oligodendrocytosis and secondary axonal damage. Furthermore, this appears to be the first study of the cuprizone model to also identify alterations in the proteomes of skeletal muscle, spleen and peripheral blood mononuclear cells. Notably, protein disulphide isomerase was not detected in the cuprizone cohort; its absence has been linked to reduced major histocompatibility class I assembly and reduced antigen presentation. Overall, the results suggest that, like experimental autoimmune encephalomyelitis, results from the standard cuprizone model should be carefully considered relative to clinical multiple sclerosis. 相似文献
974.
E. I. Surikova I. A. Goroshinskaja G. A. Nerodo E. M. Frantsiyants M. L. Malejko E. V. Shalashnaja P. S. Kachesova L. A. Nemashkalova A. V. Leonova 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2016,10(4):335-340
According to modern concepts, a malignant tumor is a complex dynamic system possessing numerous links with both the immediate environment and remote non-malignant tissues and organs. Changes in their redox balance can result in disruption of the normal tissue control. The aim of our study was to compare activity of enzymes influencing the redox state in the tumor tissue, peritumoral area, and nonmalignant tissues (taken by resection line) at various histological tumor variants. We found similar close level of reduced glutathione in the tissues of gastric adenocarcinoma and vulvar squamous cell carcinoma; however, dynamics of this parameter in the tumor surrounding tissues was different. In contrast to gastric adenocarcinoma, vulvar squamous cell carcinoma was characterized by a significant increase in glutathione content in the tumor tissue and increased activity of all investigated enzymes of the glutathione system in the tumor tissue and its peritumoral area as compared with the surrounding non-malignant tissue. These results underlie existence of clear differences in the functioning of the redox regulatory systems in the tumor and surrounding tissues of various histological origin and localization; these differences may be possibly attributed to different mechanisms involved in maintenance of the redox balance in the originally non-malignant tissues. 相似文献
975.
Tapas K. Nandi Hridoy R. Bairagya Bishnu P. Mukhopadhyay K. Sekar Dipankar Sukul Asim K. Bera 《Journal of biosciences》2009,34(1):27-34
The role of invariant water molecules in the activity of plant cysteine protease is ubiquitous in nature. On analysing the
11 different Protein DataBank (PDB) structures of plant thiol proteases, the two invariant water molecules W1 and W2 (W220
and W222 in the template 1PPN structure) were observed to form H-bonds with the Ob atom of Asn 175. Extensive energy minimization and molecular dynamics simulation studies up to 2 ns on all the PDB and solvated
structures clearly revealed the involvement of the H-bonding association of the two water molecules in fixing the orientation
of the asparagine residue of the catalytic triad. From this study, it is suggested that H-bonding of the water molecule at
the W1 invariant site better stabilizes the Asn residue at the active site of the catalytic triad. 相似文献
976.
977.
S M el Shoura 《Journal of morphology》1987,193(1):91-98
Gene's organ of the camel tick Hyalomma (Hyalomma) dromedarii is located in the anterodorsal region of the body cavity ventrad to the scutum. It consists of a short stalk, dividing posteriorly into 2 pairs of horns and then into tubular glands. In unfed ticks, the epithelial layer of both the stalk and horns is lined internally by 2 cuticular layers; an inner, thin, greatly folded, dense layer surrounds the organ main lumen, and an outer, thick, slightly folded, less dense layer abuts the cell apices. Only the inner cuticular layer extends into the horn posterior region and appears perforated with numerous pore canals and covered with fine, cuticular projections. The horn and tubular glands epithelium is structurally consistent with a secretory function that apparently increases as feeding progresses. During oviposition, the inner cuticular layer unfolds and inflates into a pair of balloonlike structures that evert through the organ external aperture to receive and manipulate each egg as it is laid, coating it with a waxy layer that prevents desiccation. The fine cuticular projections may have a function in gripping the eggs as they leave the vagina. This organ appears to be everted by hydrostatic pressure from the hemolymph and is retracted by muscles. 相似文献
978.
One particular kind of structure offers possible explanations, for long-term memory, efficient consolidation of stored information
from the environment, clustering of data strings and multimodal functioning. It is a possible model for pieces of neural structure
and its use offers a uniform method for both studying and constructing an extensive class of mechanisms. 相似文献
979.
L Galeazzi G Turchetti G Grilli G Groppa S Giunta 《Applied and environmental microbiology》1986,52(6):1433-1435
Chlorpromazine was used to perform a test for the detection of microbial peroxidase activities. The compound acts as both a cell permeabilizer and a reagent in the procedure developed which allows the detection of peroxidase and peroxidase like reactions both semiquantitatively in whole cell determinations and quantitatively in cell-free supernatants. 相似文献
980.
Attachment of Entamoeba histolytica to glass in a defined maintenance medium: specific requirement for cysteine and ascorbic acid 总被引:2,自引:0,他引:2
Cysteine and ascorbic acid were previously shown to be required by Entamoeba histolytica trophozoites for attachment to glass, elongation, and ameboid movement as well as for short-term (12-24 h) survival in a balanced salt solution containing bovine serum albumin and a vitamin solution (Maintenance Medium 1). If the only function of cysteine and ascorbate was to decrease the redox potential, other reducing agents should be effective. However, the requirement for cysteine in the presence of ascorbic acid was highly specific. Equally effective were D- and L-cysteine; however, of many other compounds tested, only thioglycolic acid, ascorbic acid, or L-cystine (in decreasing order) were somewhat active. Under N2 atmosphere, cysteine and ascorbic acid were still required, although their concentrations could be halved. The ability to attach in the maintenance medium was irreversibly lost after only 5 min of cysteine-ascorbic acid deprivation; however, there was no decrease in viability when the amebae were transferred to growth medium within 30 min. Cysteine thiol groups in the medium were oxidized rapidly regardless of the concentration of ascorbic acid or the presence of amebae; however, ascorbic acid prolonged attachment of amebae. 相似文献