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971.
J F Kahn F Huart B Kapitaniak H Monod 《European journal of applied physiology and occupational physiology》1986,55(1):88-92
Sixteen subjects (eight women and eight men, age 20-25 years) carried out in the seated position, isometric contractions sustained until exhaustion of the digital flexors. The subject's arm was placed in two positions, high and low. The muscle tensions used were 30, 40 and 50% of maximum voluntary contraction (MVC). Under these conditions, for a given relative force, the duration of contraction (limit-time) was not modified by the arm position. In the male subjects, increases in heart rate (HR) and systolic blood pressure (SBP) were slightly more pronounced in the low than the high position, but the differences were not significant. Limit times in the high position were similar to those in the low position, and, in the absence of an increase in HR and SBP, this seemed to be due to an increase in cardiac output consequent upon a transient improvement in venous return together with an increase in the coefficient of oxygen utilization. 相似文献
972.
Molecular cloning, sequence analysis and mRNA expression of human ADP-ribosylation factor 总被引:1,自引:0,他引:1
The ADP-ribosylation factor (ARF) is the small (21 kb) GTP-binding protein required for the efficient cholera toxin-catalyzed ADP-ribosylation of purified Gs, the stimulating regulatory component of adenylate cyclase. Human ARF cDNA clones were obtained from a human cDNA library by cross-species hybridization with bovine ARF1, and the nucleotide and deduced amino acid sequences were determined. Comparison of the sequences of human and bovine ARF1 showed 90% identity at the nucleotide level and 100% identity at the amino acid level, demonstrating the highly conserved nature of the ARF protein. Using human ARF cDNA as the probe, we have detected ARF messenger RNA (approximately 2.2-2.3 kb) in a wide variety of human tissues and tumor cell lines. 相似文献
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Christian Moguet Camille Gonzalez Antoine Sallustrau Stéphanie Gelhaye Thierry Naas Stéphanie Simon Hervé Volland 《Microbial biotechnology》2022,15(2):603-612
Early detection of expanded-spectrum cephalosporin (ESC) resistance is essential not only for an effective therapy but also for the prompt implementation of infection control measures to prevent dissemination in the hospital. We have developed and validated a lateral flow immunoassay (LFIA), called LFIA-CTX test, for the detection of ESC (cefotaxime) hydrolytic activity based on structural discrimination between the intact antibiotic and its hydrolysed product. A single bacterial colony was suspended in an extraction buffer containing cefotaxime. After a 30-min incubation, the solution is loaded on the LFIA for reading within 10 min. A total of 348 well-characterized Gram-negative isolates were tested. Among them, the 38 isolates that did not express any cefotaxime-hydrolysing β-lactamase gave negative results. Of the 310 isolates expressing at least one cefotaxime-hydrolysing β-lactamase, all were tested positive, except three OXA-48-like producers, which were repeatedly detected negative. Therefore, the sensitivity was 99.1% and the specificity was 100%. The LFIA-CTX test is efficient, fast, low-cost and easy to implement in the workflow of a routine microbiology laboratory. 相似文献
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Integrated assessment models are in general not constrained by mineral resource supply. In this paper, we introduce a material accounting method as a first step toward addressing the raw materials gap in the TIMES integrated assessment model (TIAM‐FR version). The method consists of attributing process‐based life cycle inventories (LCIs) taken from the ecoinvent 3.3 database to the TIAM‐FR technology processes constituting the global energy system. We demonstrate the method performing a prospective exercise on the electricity‐generating sector in a second shared socioeconomic pathway (SSP2) baseline scenario on the 2010–2100 time horizon. We start by disaggregating the LCIs into three separate life phases (construction, operation, and decommissioning) and coupling them to their respective TIAM‐FR electric outputs (new capacities, electricity production, and end‐of‐life capacities) in order to estimate the annual mineral resource requirements. Prospective uses of fossil fuels and metallic and nonmetallic mineral resources are quantified dynamically at the life phase and regional levels (15 world regions). The construction of hydropower, solar power, and wind power plants generate increasing use of metallic and nonmetallic mineral resources in successive peak and valley periods. However, the use of fossil fuels is much higher than the use of mineral resources all along the horizon. Finally, we evaluate how sensitive the global material use is to the allocation of a share of infrastructure activities to the decommissioning phase. This approach could be extended to other integrated assessment models and possibly other energy sectors. 相似文献
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