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91.
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93.
Sequencing-based typing of MICA reveals 33 alleles: a study on linkage with classical HLA genes 总被引:1,自引:0,他引:1
94.
With complete genome sequences now available for several prokaryotic and eukaryotic organisms, biological researchers are charged with the task of assigning molecular and cellular functions to thousands of predicted gene products. To address this problem, the field of proteomics seeks to develop and apply methods for the global analysis of protein expression and protein function. Here we review a promising new class of proteomic strategies that utilizes synthetic chemistry to create tools and assays for the characterization of protein samples of high complexity. These approaches include the development of chemical affinity tags to measure the relative expression level and post-translational modification state of proteins in cell and tissue proteomes. Additionally, we discuss the emerging field of activity-based protein profiling, which aims to synthesize and apply small molecule probes that monitor dynamics in protein function in complex proteomes. 相似文献
95.
Increased rate of force development and neural drive of human skeletal muscle following resistance training. 总被引:9,自引:0,他引:9
Per Aagaard Erik B Simonsen Jesper L Andersen Peter Magnusson Poul Dyhre-Poulsen 《Journal of applied physiology》2002,93(4):1318-1326
The maximal rate of rise in muscle force [rate of force development (RFD)] has important functional consequences as it determines the force that can be generated in the early phase of muscle contraction (0-200 ms). The present study examined the effect of resistance training on contractile RFD and efferent motor outflow ("neural drive") during maximal muscle contraction. Contractile RFD (slope of force-time curve), impulse (time-integrated force), electromyography (EMG) signal amplitude (mean average voltage), and rate of EMG rise (slope of EMG-time curve) were determined (1-kHz sampling rate) during maximal isometric muscle contraction (quadriceps femoris) in 15 male subjects before and after 14 wk of heavy-resistance strength training (38 sessions). Maximal isometric muscle strength [maximal voluntary contraction (MVC)] increased from 291.1 +/- 9.8 to 339.0 +/- 10.2 N. m after training. Contractile RFD determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction increased from 1,601 +/- 117 to 2,020 +/- 119 (P < 0.05), 1,802 +/- 121 to 2,201 +/- 106 (P < 0.01), 1,543 +/- 83 to 1,806 +/- 69 (P < 0.01), and 1,141 +/- 45 to 1,363 +/- 44 N. m. s(-1) (P < 0.01), respectively. Corresponding increases were observed in contractile impulse (P < 0.01-0.05). When normalized relative to MVC, contractile RFD increased 15% after training (at zero to one-sixth MVC; P < 0.05). Furthermore, muscle EMG increased (P < 0.01-0.05) 22-143% (mean average voltage) and 41-106% (rate of EMG rise) in the early contraction phase (0-200 ms). In conclusion, increases in explosive muscle strength (contractile RFD and impulse) were observed after heavy-resistance strength training. These findings could be explained by an enhanced neural drive, as evidenced by marked increases in EMG signal amplitude and rate of EMG rise in the early phase of muscle contraction. 相似文献
96.
Regalado EL Rodríguez M Menéndez R Concepción AA Nogueiras C Laguna A Rodríguez AA Williams DE Lorenzo-Luaces P Valdés O Hernandez Y 《Marine biotechnology (New York, N.Y.)》2009,11(1):74-80
Daily topical application of the aqueous ethanolic extract of the marine sea grass, Thalassia testudinum, on mice skin exposed to UVB radiation resulted in a dose-dependent recovery of the skin macroscopic alterations over a 6-day
period. Maximal effect (90%) occurred at a dose of 240 μg/cm2, with no additional effects at higher doses. Bioassay-guided fractionation of the plant extract resulted in the isolation
of thalassiolin B (1). Topical application of 1 (240 μg/cm2) markedly reduces skin UVB-induced damage. In addition, thalassiolin B scavenged 2,2-diphenyl-2-picrylhydrazyl radical with
an EC50 = 100 μg/ml. These results suggest that thalassiolin B is responsible for the skin-regenerating effects of the crude extract
of T. testudinum.
Erik L. Regalado and María Rodríguez have contributed equally to this work and should be considered as first authors. 相似文献
97.
98.
This study describes the effect of soil fauna and vegetation on the development of landscapes and how these actually control
soil formation, geomorphological development and hydrological response. The study area is located in a semi-natural deciduous
forest on marl in Luxembourg, with a strong texture contrast in the soil at 15–25 cm depth (luvic planosols).
The methodology applied is both based on hydrological and geomorphological field measurements on runoff, sediment yield, perched
water table dynamics, geomorphological survey, pedological survey and measurements related to in situ ectorganic horizon dynamics
and litter decay, soil animal activity, as well as measurements of dynamic soil properties such as soil moisture and swelling
and shrinkage.
The results show that there is a positive feedback between tree type, soil fauna activity and the development of pipes, partial
areas, soils and geomorphology. The landscape can be divided into two main types: Areas where Stellario-Carpinetum vegetation
and partial areas are common and areas with Milio-Fagetum vegetation on dry slopes, which are differentiating more and more
over time as a result of ongoing geo-ecosystem processes, and which also reflected in their sediment yield. The hydrological
response is highly different for both landscape compartments as they are dominated by matrix (Beech) and pipe flow (Hornbeam)
respectively. Soil fauna and tree type drive both soil and geomorphological evolution and they both can be considered as important
ecosystem engineers. 相似文献
99.
Expression of the Escherichia coli dam gene 总被引:7,自引:0,他引:7
100.