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This paper presents a new hardware and software system that allows not only recording the EMG of different groups of the respiratory muscles but also performing its amplitude-frequency analysis to determine the change in the contribution to the function of breathing of the respiratory muscles and detect early signs of fatigue of the respiratory muscles. The presented system can be used for functional diagnostics of breath in patients and healthy subjects and athletes.  相似文献   
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A comparative morphometric study was performed with MRI brain scans of term- and preterm-born infants. The structural characteristics of the brain were analyzed using conventional morphometric indices, and a novel quantitative parameter, the corpus callosum coefficient (kCC), was introduced based on patterns of the prenatal cortex ontogeny. All these quantitative indices reflected anatomical features of the preterm brain. It was found that reduced kCC values in preterm infants were associated with an altered proportion between the rostral and caudal segments of the corpus callosum. The threshold kCC value was established that allowed significant discrimination between the brains of full-term and preterm infants.  相似文献   
414.
Microbial metalloenzymes constitute a large library of biocatalysts, a number of which have already been shown to catalyze the breakdown of toxic chemicals or industrially relevant chemical transformations. However, while there is considerable interest in harnessing these catalysts for biotechnology, for many of the enzymes, their large-scale production in active, soluble form in recombinant systems is a significant barrier to their use. In this work, we demonstrate that as few as three mutations can result in a 300-fold increase in the expression of soluble TrzN, an enzyme from Arthrobacter aurescens with environmental applications that catalyzes the hydrolysis of triazine herbicides, in Escherichia coli. Using a combination of X-ray crystallography, kinetic analysis, and computational simulation, we show that the majority of the improvement in expression is due to stabilization of the apoenzyme rather than the metal ion-bound holoenzyme. This provides a structural and mechanistic explanation for the observation that many compensatory mutations can increase levels of soluble-protein production without increasing the stability of the final, active form of the enzyme. This study provides a molecular understanding of the importance of the stability of metal ion free states to the accumulation of soluble protein and shows that differences between apoenzyme and holoenzyme structures can result in mutations affecting the stability of either state differently.  相似文献   
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Influence of GABA application on ability of sensorimotor cortical neurones to form conditioned cellular reactions was studied in chronic experiments on rabbits. Neuronal reactions were analysed at the initial stage of eye-lid conditioning. GABA application in a period of presentation of paired conditioned and unconditioned stimuli disturbed formation of inhibitory conditioned cellular reactions and did not influence elaboration of activating responses. Plastic changes underlying the process of formation of inhibitory conditioned neuronal reactions are supposed to be of intracortical nature.  相似文献   
418.
Lithium hydroxybutyrate (200 mg/kg) has been shown to depress the development of carrageenan inflammation. Subcutaneous drug injection in chronic inflammation of the mucous membrane in the hamster cheek pouch restored the blood flow, checked dilatation of the blood vessels, decreased their permeability and prevented necrosis of the mucous membranes. Subcutaneous drug injection depressed all the signs of both phases of acute inflammatory reaction in the rat hind foot and promoted preservation of the hind foot function. Therefore, lithium hydroxybutyrate may be an effective preparation for the treatment of inflammation.  相似文献   
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Plasma Physics Reports - The paper presents a review of modern works on gasdynamic flow control using a highly nonequilibrium pulsed plasma. The main attention is paid to the effects based on...  相似文献   
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