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Background
Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH. 相似文献2.
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Konstantin V. Pochivalov Yaroslav V. Kudryavtsev Tatyana N. Lebedeva Lyubov A. Antina Anna N. Ilyasova Mikhail Yu. Yurov Andrey V. Basko Alexander E. Zavadskii 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2225-2233
Constructing phase diagrams for the mixtures of semicrystalline polymers and low molecular mass substances by DSC can meet with difficulties in the case of slow polymer crystallization. A problem of this kind is encountered for high-energy compositions poly[3,3-bis(azidomethyl)oxetane] (PBAMO)–2,4-dinitro-2,4-diazapentane (DNAP). In this study, the experimental phase diagram PBAMO–DNAP is constructed by an optical method, which makes it possible to visualize structural transformations. The kinetic studies by DSC and XRD reveal that 30–50 days of storing a homogenized PBAMO–DNAP mixture at room temperature are needed to attain stationary values of the crystallinity degree and heat of fusion. Even after that, the DSC method cannot deliver a solubility curve of DNAP in PBAMO, which is naturally generated by the optical method. This curve separates a domain of physical gels, effectively crosslinked by polymer crystallites and swollen with the plasticizer molecules, from a two-phase domain, in which the above gel reaches osmotic equilibrium with the pure plasticizer. It is also shown that the melting temperature of DNAP drops with growing the PBAMO content in the mixture, which is consistent with a decrease in the mean size of plasticizer crystals formed in polymer pores during the previous cooling. 相似文献
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S. Sh. Rashidova S. Sh. Atamatova D. D. Ilyasova U. A. Azizov 《Reaction Kinetics and Catalysis Letters》1979,10(3):263-266
The selective catalytic effect of transition metal complexes (in particular cobalt and manganese) with polymeric ligands is shown on the example of the liquid-phase oxidation of ethylbenzene. The catalytic activity depends on both the structure of the polymeric matrix and the nature of metal.
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G. T. Sukhanov A. G. Sukhanova Yu. V. Ilyasova 《Chemistry of Heterocyclic Compounds》2006,42(9):1197-1199
The reaction of 3-nitro-5-R-1,2,4-triazoles with diethyl sulfate gives 1-ethyl-3-R-5-nitro-, 4-ethyl-3-nitro-5-R-1,2,4-triazoles,
1,4-diethyl-, 1,4-diethyl-3-methyl-1,2,4-triazol-5-ones, and 1,4-diethyl-3-nitro-5-R-1,2,4-triazolium salts. When compared
with the use of dimethyl sulfate as alkylating agent the ethylation products have a markedly increased fraction of triazolones
(up to 30–37%) and a somewhat lowered yield of nitrotriazolium salts (up to 6–10%). The reaction time is increased by an order.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1378–1381, September, 2006. 相似文献
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D. I. Leipuskaya V. I. Drynkin D. M. Voinkov I. F. Brovchuk K. I. Ilyasova B. V. Belenki 《Journal of Radioanalytical and Nuclear Chemistry》1980,57(2):407-416
A method has been worked out of multi-elemental instrumental neutron-activation analysis INAA of small weights some mg of
monomineral fractions of sulfide minerals pyrites, galenites, chalcopyrites, arsenopyrites, bornites, chalcosines and quartzes.
The samples were irradiated in a nuclear reactor under a flux of 1.3·1013 n·cm−2·s−1. For measuring the gamma radiation of the exposed samples Ge(Li) gamma-spectrometers with semiconductor detectors were used.
Determined in sulfide monofractions were the elements: Co, Sc, Ag, Se, Sb, Cr, Fe, Zr; rare-earth elements: Ce, Sm, Eu and
others at content levels of 10−1−10−4%. In quartzes they were: Mn, Na, Sb, Cr, Sc, Fe, Co at content levels of 10−5−10−7% and Au to n×10−9%. A special method has been worked out for the determination of In in sulfides with the irradiation of samples in a cadmium
screen. An example is cited of using the method for studying some peculiar features of the genetics of copper pyrite deposits.
The data on the distribution of admixture elements in sulfide monofractions produced in this work made it possible to conclude
that the oreformation in the deposits has a stage-by-stage character. 相似文献
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A. N. Ilyasova Y. V. Kudryavtsev T. N. Lebedeva I. V. Levashova Yu. A. Flyagina K. V. Pochivalov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(3):425-429
Complete phase diagrams for mixtures of low-density polyethylene with p- and m-xylene are plotted by optical means in developing the concept of which partially crystalline polymers are microstructured liquids. It is shown that in contrast to the ones presented in the literature, both diagrams contain the solubility boundary curve of the low-molecular weight component in the polymer, above which the polyethylene has the structure of a single-phase gel (crosslinks formed by crystallites and amorphous regions saturated with xylene). At the figurative point on the diagrams, a situation is observed in which the dissolution of all the liquid contained in the initial two-phase system in the polymer is accompanied by its simultaneous complete amorphization. The parameters of the figurative point allow us to estimate the thermodynamic affinity of different alkylbenzenes toward polyethylene. 相似文献
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A simple method to generate an effective electron-ion interaction pseudopotential from the energy wave number characteristic
obtained by first principles calculations has been suggested. This effective potential has been used, in third order perturbation,
to study the effect of three-body forces on the lattice dynamics of noble metals. It is found that three-body forces, in these
metals, do play an important role. The inclusion of such three-body forces appreciably improves the agreement between the
experimental and theoretical phonon dispersion curves. 相似文献
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Bilińska B Pilawa B Zawada Z Wylegała E Wilczok T Dontsov AE Sakina NL Ostrovsky MA Ilyasova VB 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(10):2257-2264
Electron spin resonance (ESR) examinations of human retinal pigment epithelium melanosomes isolated from eyes of young and old donors were carried out. The examined ESR signal was a single line, which is characteristic for free radicals of eumelanin o-semiquinones. The content of free radicals related to melanosomes dry weight for samples from older donors (ages over 45 years) were higher than for sample from younger donors (between 14 and 22 years). Simultaneously, the content of free radicals calculated for one melanosome is constant and does not depend on age. The homogeneous broadening of the recorded ESR lines shows that there are no isolated spin packets in all investigated melanin samples. Slow spin-lattice (T1 approximately 10(-5) s) and fast spin-spin (T2 approximately 10(-8) s) relaxation processes occur in these samples. Saturation of the ESR lines at low microwave power was measured. High concentration of free radicals in melanosome samples was responsible for the fast spin-spin relaxation process. 相似文献
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