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排序方式: 共有880条查询结果,搜索用时 15 毫秒
1.
In experiments on male rabbits with the lack of insulin it is been revealed violations after the past immobilization the intensivity and duration of neutrophilic leukocytosis decrease, contents of lysosomes in neutrophils, activity of acid phosphatase. By lysosomal ferments don't determine the can observer discordance of processes of coagulation, fibrinolysis, kininogenesis. 相似文献
2.
1. | Raising the cobalt concentration from 0 to 40% improves the oxidation resistance of Ni–20Cr alloys, since the amount of Cr2O3 in the scale increases. The oxidation resistance is highest for the alloy with 40% Co. Larger amounts of Co up to 70% lead to the formation of CoO in the scale and smaller amounts of chromium oxide, which has a negative effect on the oxidation resistance of Ni–Cr alloys. |
2. | The addition of up to 25% Fe to Ni–20Cr–Co alloys reduces the amount of Cr2O3 in the scale and lowers the oxidation resistance. With larger amounts of Fe the amount of Cr2O3 in the scale again increases, the oxidation resistance increasing correspondingly. Alloys with 45% Fe have the same oxidation resistance as alloys without Fe. |
3.
R. I. Kozlov O. R. Kozlova 《Journal of Computer and Systems Sciences International》2009,48(2):262-271
Modification and extension of procedures of strict analysis of stability and estimates of domains of attraction based on the reduction method with sublinear vector Lyapunov function is given for sufficiently wide class of nonlinear stabilization systems of continuous objects using piecewise constant control formed using discrete state measurements. The new type of realization of heterogeneous comparison systems in the form of interconnected differential and discrete impulse subsystems with varying right-hand side allowing to avoid preliminary discretization of the original system and thus increasing accuracy of investigations is proposed. In the case of nonlinearities (including those with respect to control and measurements), limited by semi-homogeneous functions. Constructive conditions of exponential stability with necessary quantitative estimates are formulated. Application to investigation of stability of economic growth in the Phillips-Bergstrom model with discrete monetary regulation is presented. The paper consists of two parts. In this part, the studied models are described, the studied stability property is defined, procedures for construction of vector Lyapunov function and comparison system are given, and some of their specific features are established. 相似文献
4.
Yilin Han Marianne King Evgenii Tikhomirov Povilas Barasa Cleide Dos Santos Souza Jonas Lindh Daiva Baltriukiene Laura Ferraiuolo Mimoun Azzouz Maurizio R. Gullo Elena N. Kozlova 《International journal of molecular sciences》2022,23(10)
Three-dimensional (3D) cultures, so-called organoids, have emerged as an attractive tool for disease modeling and therapeutic innovations. Here, we aim to determine if boundary cap neural crest stem cells (BC) can survive and differentiate in gelatin-based 3D bioprinted bioink scaffolds in order to establish an enabling technology for the fabrication of spinal cord organoids on a chip. BC previously demonstrated the ability to support survival and differentiation of co-implanted or co-cultured cells and supported motor neuron survival in excitotoxically challenged spinal cord slice cultures. We tested different combinations of bioink and cross-linked material, analyzed the survival of BC on the surface and inside the scaffolds, and then tested if human iPSC-derived neural cells (motor neuron precursors and astrocytes) can be printed with the same protocol, which was developed for BC. We showed that this protocol is applicable for human cells. Neural differentiation was more prominent in the peripheral compared to central parts of the printed construct, presumably because of easier access to differentiation-promoting factors in the medium. These findings show that the gelatin-based and enzymatically cross-linked hydrogel is a suitable bioink for building a multicellular, bioprinted spinal cord organoid, but that further measures are still required to achieve uniform neural differentiation. 相似文献
5.
I V Lerina A M Belous T L Kolesnik G N Shatrov V F Kozlova A N Za?tsev 《Voprosy pitaniia》1990,(1):61-64
Toxicologic and hygienic study of a pigment from abattoir blood--carboxyn (based on carboxyhemoglobin) was conducted on noninbred white rats in subacute (3 months) and chronic (12 months) experiments. The condition of the animals, their bw growth, blood morphology, erythrocyte sedimentation rate, the content of hemoglobin, protein and iron in the blood serum were evaluated. Activity of the following enzymes was studied: catalase and sorbitol dehydrogenase--in the blood serum; glucose 6-phosphate dehydrogenase, lactate dehydrogenase and cytochrome P-450 content--in the liver. Internal organs of the rats were subjected to histological investigation. The data obtained have evidenced the absence of some signs of biotransformation of the red complex of carboxyhemoglobin, or its toxic effect on the experimental animals. It has been concluded that carboxyn can be used as a coloring component in the production of sausage (in the amount of up to 2% of the sausage meat mass). 相似文献
6.
A N Mironova V L Kozlova Z D Volkova G I Filippova N I Fedina T B Alymova S P Vologdina E I Gorshkova 《Voprosy pitaniia》1990,(5):51-53
Biological properties of grape seed oil, included into the ration of animals in the amount of 25% of calorie value during 11 weeks, were studied in growing male rats. It has been established that deodorized grape seed oil is close to sunflower oil by its chemical and biological properties. The possibility of using grape seed oil as full value food vegetable oil has been validated. 相似文献
7.
V M Krasnopevtsev L S Trofimenko A V Istomin Iu A Noarov T I Kozlova 《Voprosy pitaniia》1989,(5):40-43
Actual nutrition, health state and physical working capacity were studied in schoolchildren of three age groups after intake of the polyvitamin "Undevitum" during a month. The results of the investigation conducted have shown that prophylactic measures produced a positive effect on the schoolchildren aged from 11 to 13 and from 14 to 17 years who received 1 degree of "Undevitum" daily. No positive effect was recorded in schoolchildren aged 7-10 years who received 1 degree of "undevitum"/day, every other day. 相似文献
8.
A. A. Yugov S. S. Malahov A. A. Donskov M. P. Duhnovskii S. N. Knyazev Yu. P. Kozlova T. G. Yugova I. A. Belogorokhov 《Semiconductors》2016,50(3):411-414
The effect of the type of substrate, sapphire substrate (c- and r-orientation) or GaN/Al2O3 template (c- and r-orientations), on the nitridation of an amorphous titanium nanolayer is shown. The effect of the titanium-nanolayer thickness on thick GaN epitaxial layer self-separation from the substrate is revealed. The titanium-nanolayer thickness at which thick GaN layer is reproducibly self-separated is within 20–40 nm. 相似文献
9.
N. Miura N. V. Kozlova K. Dörr J. Freudenberger L. Schultz O. Drachenko K. Sawano Y. Shiraki 《Journal of Low Temperature Physics》2010,159(1-2):222-225
Shubnikov-de Haas oscillation and cyclotron resonance were studied for high mobility p-type Ge channels in strained Ge/Si1?x Ge x quantum wells, using pulsed high magnetic fields up to 50 T. Fine quantum oscillations were observed in ρ xx . Reflecting the complex Landau level structure in the nearly degenerate valence bands, the Fourier transform of the oscillatory spectra consists of several peaks. Cyclotron resonance was measured at photon energies between 10 and 17 meV. Two well-defined resonance peaks were observed in two samples with different x, resulting in different strains. A large non-parabolicity and large strain dependence of the effective masses were observed. 相似文献
10.