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Spirometric, gasometric and electrocardiogarphic studies were carried out in 17 patients at rest, who were treated surgically for extreme obesity (overweight from 52 to 175 per cent in relation to the normal weight). The measurements were made before operation. It was found that the mean spirometric values were within the range of acceptable deviations from the normal value. The residual volume showed a tendency towards decreasing, especially in young patients. The values of dynamic parameters indicated a tendency towards ventilatory changes of a restrictive type in both groups. Minute ventilation at rest increased proportionally to obesity. Decreased values of respiratory equivalent indicated a good economy of respiration in obese persons when at rest. The mean gasometric values in capillary blood at rest were also within the acceptable range of abnormalities. Electrocardiographic tracings taken at rest showed considerable changes in the group of more obese persons. 相似文献
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The review, discusses current data on biological indices that respond specifically to changes in Zn safety. The most reliable is the method of Zn safety evaluation based on its stores in organism measurement by means of stable isotopes. Zn status estimation by its levels determination in different kinds of available biological material (plasma, serum and whole blood, saliva, sweat, urine, hair, tissue samples) has different limitations. Some advances have so named physiological Zn safety criteria however their use is poorly validated or complicated with estimations subjectivity. Currently the first place belongs to a group of methods based on measurement of Zn-dependent proteins levels or activities together with their genes expression especially for such Zn-dependent enzyme as alkaline phosphatase. 相似文献
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A. G. Dedov O. A. Shlyakhtin A. S. Loktev G. N. Mazo S. A. Malyshev S. I. Tyumenova A. E. Baranchikov I. I. Moiseev 《Petroleum Chemistry》2018,58(1):43-47
Novel catalysts based on neodymium–calcium cobaltate–nickelate complex oxides for the partial oxidation of methane to synthesis gas have been synthesized and studied using catalyst precursors with the general formula NdCaCo1–xNi x O n (x = 0, 0.2, 0.4, 0.6, 0.8, 1) prepared by the solid state synthesis method. It has been shown that the synthesized samples form a series of solid solutions with a K2NiF4 structure at x ≤ 0.8 or a rhombically distorted K2NiF4 structure at x = 1. The products of conversion of the resulting precursors in a methane–oxygen mixture at high temperatures have shown high methane conversions and synthesis gas yields. The highest values of these parameters have been achieved in the presence of catalysts synthesized by the reduction of NdCaCo0.4Ni0.6O n and NdCaNiO n precursors. The complete replacement of cobalt with nickel has led to an increase in the synthesis gas yield; however, it has been found that the resulting catalyst is prone to carbonization. It has been determined that an optimum nickel to cobalt ratio in the catalyst composition provides the formation of a carbonization-resistant catalyst. 相似文献
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Le Quentrec É. Mazo L. Baudrier É. Tajine M. 《Journal of Mathematical Imaging and Vision》2022,64(8):869-891
Journal of Mathematical Imaging and Vision - In many applications of geometric processing, the border of a continuous shape and of its digitization (i.e., its pixelated representation) should be... 相似文献
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A technique for local upscaling of absolute permeability is proposed intended for the superelement modeling of petroleum reservoir development. The upscaling is performed for every block of an unstructured superelement grid based on solving a series of stationary one-phase flow in reservoir problems on a refined grid with the initial permeability field under various boundary conditions reflecting the characteristic structural variants of the filtrational flow and taking into account the presence or absence of wells inside the block. The resulting components of the effective permeability tensor in each superelement are sought from the solution of the problem on minimizing the deviations of the normal flows through the faces of the superelement averaged on a refined computational grid from those approximated on a coarse superelement grid. The application of the method is demonstrated by examples of the reservoir of the periodic and nonperiodic structure. The method is compared with the traditional techniques for local upscaling. 相似文献