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41.
42.
Introduction
The vast difference in the abundance of different proteins in biological samples limits the determination of the complete proteome of a cell type, requiring fractionation of proteins and peptides before MS analysis. 相似文献43.
Stairway climbing provides a ubiquitous and inconspicuous method of burning calories. While typically two strategies are employed for climbing stairs, climbing one stair step per stride or two steps per stride, research to date has not clarified if there are any differences in energy expenditure between them. Fourteen participants took part in two stair climbing trials whereby measures of heart rate were used to estimate energy expenditure during stairway ascent at speeds chosen by the participants. The relationship between rate of oxygen consumption () and heart rate was calibrated for each participant using an inclined treadmill. The trials involved climbing up and down a 14.05 m high stairway, either ascending one step per stride or ascending two stair steps per stride. Single-step climbing used 8.5±0.1 kcal min−1, whereas double step climbing used 9.2±0.1 kcal min−1. These estimations are similar to equivalent measures in all previous studies, which have all directly measured The present study findings indicate that (1) treadmill-calibrated heart rate recordings can be used as a valid alternative to respirometry to ascertain rate of energy expenditure during stair climbing; (2) two step climbing invokes a higher rate of energy expenditure; however, one step climbing is energetically more expensive in total over the entirety of a stairway. Therefore to expend the maximum number of calories when climbing a set of stairs the single-step strategy is better. 相似文献
44.
A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics. 相似文献
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McKimmie CS Fraser AR Hansell C Gutiérrez L Philipsen S Connell L Rot A Kurowska-Stolarska M Carreno P Pruenster M Chu CC Lombardi G Halsey C McInnes IB Liew FY Nibbs RJ Graham GJ 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(5):3353-3363
D6 scavenges inflammatory chemokines and is essential for the regulation of inflammatory and immune responses. Mechanisms explaining the cellular basis for D6 function have been based on D6 expression by lymphatic endothelial cells. In this study, we demonstrate that functional D6 is also expressed by murine and human hemopoietic cells and that this expression can be regulated by pro- and anti-inflammatory agents. D6 expression was highest in B cells and dendritic cells (DCs). In myeloid cells, LPS down-regulated expression, while TGF-beta up-regulated expression. Activation of T cells with anti-CD3 and soluble CD28 up-regulated mRNA expression 20-fold, while maturation of human macrophage and megakaryocyte precursors also up-regulated D6 expression. Competition assays demonstrated that chemokine uptake was D6 dependent in human leukocytes, whereas mouse D6-null cells failed to uptake and clear inflammatory chemokines. Furthermore, we present evidence indicating that D6 expression is GATA1 dependent, thus explaining D6 expression in myeloid progenitor cells, mast cells, megakaryocytes, and DCs. We propose a model for D6 function in which leukocytes, within inflamed sites, activate D6 expression and thus trigger resolution of inflammatory responses. Our data on D6 expression by circulating DCs and B cells also suggest alternative roles for D6, perhaps in the coordination of innate and adaptive immune responses. These data therefore alter our models of in vivo D6 function and suggest possible discrete, and novel, roles for D6 on lymphatic endothelial cells and leukocytes. 相似文献
48.
Astrid G. Chapman Michael J. Halsey Geneen P. Hart Nigel P. Luff Brian S. Meldrum Bridget Wardley-Smith 《Journal of neurochemistry》1986,47(1):314-317
Regional amino acid concentrations were measured in rat brain fixed by microwave irradiation at three levels of elevated atmospheric pressure corresponding to different phases of the high-pressure neurological syndrome [20 atmospheres absolute (ATA), no clinical signs; 60 ATA, tremor; 85 ATA, severe tremor and myoclonic jerks]. No changes in amino acid content occurred at 20 or 60 ATA. At 85 ATA glutamine content increased in hippocampus, striatum, cerebellum, and substantia nigra, and gamma-aminobutyric acid content increased in hippocampus. It is suggested that enhanced glutamate release in various subcortical structures contributes to the myoclonic activity observed at 85 ATA. 相似文献
49.
Male mice were exposed to 50 atmospheres absolute (ATA). He for 30 min, twice weekly for 5 wk and their fertility assessed by subsequently mating with untreated virgin females. The exposure schedule was designed to provide compression and decompression times the same as previous positive studies of hyperbaric-induced subfertility but with much shorter periods at maximum pressure (30 min vs. 24 h). We postulated that, if subfertility were associated with exposure to pressure per se rather than with compression or decompression, then the present experiments would fail to produce a decrease in male fertility. The data were compared with those of a control group placed in the hyperbaric chamber at 1 ATA. The pregnancy rate for exposed vs. control mice was 89 vs. 86%, and the mean live liter size was 6.2 vs. 5.6. There were no statistically significant differences between these and other indexes of male fertility, and the results support our hypothesis that the hyperbaric-induced subfertility in male mice is not associated with these decompression procedures. 相似文献
50.
Changes in gibberellin-like activity and content of indole type auxins were investigated during grain development of the two high-lysine barley (Hordeum vulgare L.) genotypes Sv 73608 and Risø 1508, and their corresponding normal cultivars Mona and Bomi. A peak in gibberellin-like activity was found in developing grains of the normal cultivars about 18 days after anthesis, whereas the grains of the high-lysine genotypes showed a two to five times higher maximum about 3–4 days later. The auxin content of the cultivar Bomi showed a maximum between the 22nd and the 29th day after anthesis, whereas, throughout their development the grains of the mutant Risø 1508 exhibited only about 1/10 of the maximum level of auxin found in the grains of Bomi. The normal cultivar Mona also displayed higher contents of auxin than the high-lysine genotypes Sv 73608, particularly at the later stages of grain growth, but the differences in concentration were considerable smaller than for the pair ‘Bomi’—‘Risø 1508’. It is suggested that auxins play an important role in the development of barley grains. 相似文献