279 research outputs found

    Problems of confirmation of compliance of imitation leather in Russia

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    При подтверждении соответствия искусственной кожи в России возникают различные проблемы, которые связаны с непроработанными требованиями, изложенными в техническом регламенте Таможенного союза 017/2011 на искусственную кожу.At confirmation of imitation leather, compliance in Russia we are various problems that are connecting with not worked requirements stated in technical regulations of the Customs union 017/2011 on imitation leather

    Effect of Laves phase on ductile-brittle transition of 12 Pct Cr steel

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    The impact toughness of a martensitic 12 Cr-0.6 Mo-2.2 W-4 Co-0.8 Cu-VNb (in wt pct) steel subjected to tempering at 770°C for 3 hours and aging at 650°C for 643 hours was examined in the temperature range of 20 to 250°C. The steel in the tempered condition exhibits a ductile-brittle transition temperature (DBTT) of 41°C and a Charpy V-notch impact energy of 100 J/cm2 at a temperature of 20°

    Antiproliferative activity of a new derivative from the class of N-glycoside of indolo [2,3-a] pyrrolo [3,4-c] carbazoles

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    The aim of the study was to evaluate an antiproliferative activity of a new, Russian derivative of N-glycoside substituted indolocarbazole 6-amino-12-(α-L-arabinopyranosyl)indolo [2,3-a] pyrrolo [3,4-c] carbazole-5,7-dione (LCS-1208) on models of transplantable tumors of mice and on human tumors in Balb/c nude mic

    Chemical analysis of bioactive substances in seven siberian Saussurea species

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    Main groups of biologically active substances of seven siberian Saussurea species (S. controversa DC., S. latifolia Ledeb., S. parviflora (Poir.) DC., S. frolowii Ledeb, S. amara (L.) DC., S. salicifolia (L.) DC. and S. daurica Adams) have been studied using paper, thin-layer, performance liquid chromatography, IR spectroscopy, spectrophotometry and mass spectrometry with inductively coupled plasma. Siberian Saussurea species have a rich elemental composition and contain a variety of phenolic compounds, amino acids, polysaccharides. The majority of polysaccharides are accumulated by S. controversa, S. salicifolia and S. frolowii. These plants contain a significant amount of calcium that may be a species characteristic. All plants contain quercetin and its glycosides, in some species luteolin, kaempferol, glycosides of apigenin and myricetin were revealed. Phenolic acids with predominant content of caffeic, chlorogenic and cinnamic acids were found in all the species. The maximum amount of phenolic acids and flavonoids was determined in the grass of S. latifolia, S. controversa and S. daurica. Characteristic absorption bands of lactone carbonyl of sesquiterpenoids in IR spectrum found in S. latifolia, S. controversa, S. daurica, S. amara and S. salicifolia. HPLC / UV analysis showed that peaks with absorption maxima of 242-246 nm due to the presence of α,β-unsaturated ketone group in the structure of ecdysteroids were found in S. salicifolia, S. controversa, S. daurica and S. latifolia

    Структура и биологическое действие аналогов и производных биогенных полиаминов

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    Objectives. Biogenic polyamines are widely present in nature. They are characteristic of both protozoan cells and multicellular organisms. These compounds have a wide range of biological functions and are necessary for normal growth and development of cells. Violation of polyamine homeostasis can cause significant abnormalities in cell functioning, provoking various pathological processes, including oncological and neuropsychiatric diseases. The impact on the “polyamine pathway” is an attractive basis for the creation of many pharmacological agents with a diverse spectrum of action. The purpose of this review is to summarize the results of the studies devoted to understanding the biological activity of compounds of the polyamine series, comparing their biological action with action on certain molecular targets. Due to the structural diversity of this group of substances, it is impossible to fully reflect the currently available data in one review. Therefore, in this work, the main attention is paid to the derivatives, acyclic saturated polyamines.Results. The following aspects are considered: biological functionality, biosynthesis and catabolism, cell transport, and localization of biogenic polyamines in the living systems. Structural analogs and derivatives of biogenic polyamines with antitumor, neuroprotective, antiarrhythmic, antiparasitic, antibacterial, and other biological activities are represented; the relationship between biological activity and the target of exposure is reflected. It was found that the nature of the substituent, the number of cationic centers, and the length of the polyamine chain have a great influence on the nature of the effect.Conclusions. At present, the use of polyamine structures is restrained by cytotoxicity and nonspecific toxic effects on the central nervous system. Further research in the field of biochemistry, cell transport, and a deeper understanding of receptor interaction mechanisms will help making polyamines as the basis for potential drug formulation.Цели. Биогенные полиамины широко представлены в живой природе. Они характерны как для клеток простейших, так и для многоклеточных организмов. Данные соединения обладают широким спектром биологической активности и необходимы для нормального роста и развития клеток. Нарушение гомеостаза полиаминов может вызывать существенные отклонения в функционировании клетки, провоцируя протекание патологических процессов различного рода, включая онкологические и психоневрологические заболевания. Воздействие на «полиаминовый путь» является привлекательным базисом для создания ряда фармакологически активных веществ с различным спектром действия. Целью данного обзора является обобщение результатов исследований, посвященных изучению биологической активности соединений полиаминового ряда; сопоставление биологического действия с воздействием на определенные молекулярные мишени. В виду структурного многообразия данной группы веществ невозможно в полной мере отразить имеющиеся на сегодняшний момент данные в одном обзоре. Поэтому в настоящей работе основное внимание уделено производным насыщенных полиаминов ациклического строения.Результаты. В общем виде рассмотрены следующие аспекты: биологическая активность, биосинтез и катаболизм, клеточный транспорт и локализация биогенных полиаминов в живых системах. Представлены структурные аналоги и производные биогенных полиаминов, обладающие противоопухолевой, нейропротекторной, антиаритмической, противопаразитарной, антибактериальной и некоторыми другими видам биологической активности; отражена взаимосвязь между биологической активностью и мишенями воздействия. Установлено, что на характер воздействия большое влияние оказывает природа заместителя, количество катионных центров, а также длина полиаминовой цепи.Выводы. В настоящее время применение структур полиаминового ряда сдерживается наличием цитотоксичности, а также неспецифического токсического воздействия на ЦНС. Дальнейшие исследования в области биохимии, клеточного транспорта, а также более глубокое понимание механизмов рецепторного взаимодействия позволят использовать полиамины в качестве основы для создания потенциальных лекарственных препаратов

    Microstructural changes in cast martensitic steel after creep at 620°C

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    Microstructural changes in the cast steel GX12CrMoWVNbN10-1-1 (Fe-0.11 C-0.31 Si-0.89 Mn-9.57 Cr-0.66 Ni-1.01 Mo-1.00 W-0.21 V-0.06 Nb-0.05 Cu-0.05 N in wt %) have been investigated after tests for long-term strength at a temperature of 620°C in the range of stresses of 120-160 MP

    FEATURES OF GENOTYPiNG VARIABILITY OF STRAINS OF BORDETELLA PERTUSSIS ALLOCATED FROM PATIENTS WITH WHOOPING COUGH IN RUSSIA

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    On the basis of studying of features of structure of 7 genes determining major factors of pathogenicity of the causative agent of whooping cough - ptxA, ptxB, ptxC, ptxD, ptxE, ptxP and prn, features of genotyping variability of strains of B.pertussis allocated from patients with whooping cough in Russia are shown. Dynamics of formation of population of strains of the causative agent of whooping cough is tracked and is established that population of strains of B.pertussis is formed by clonal expansion of strains with, new genetic structure of major factors of pathogenicity - pertussis toxin and. pertactin. The structure of population of strains of B.pertussis causing a disease by whooping cough, at the present stage of epidemic process of a pertussis infection - domination. of strains with new «non-vaccine» alleles genes - ptxA1 (97,7 %), ptxC2 (87,4 %), prn2 (89,5 %) and. ptxP3 (93,3 %), in 2,2 % cases with ptxB2 allele and. in 1,3 % cases with. prn9 allele circulate

    Acute cerebellar ataxia in a young woman: Wernicke’s encephalopathy?

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    Wernicke’s encephalopathy (WE) is a rare but severe neurological syndrome caused by thiamine deficiency. According to the data of autopsy studies, the prevalence of WE in the general population varies from 0.4 to 2.8 per 100,000 population; the disease occurs many times more frequently in alcohol abusers than in people who lead a healthy lifestyle. These studies also showed that most cases of WE were diagnosed postmortem; less than 20% of patients with the disease were diagnosed in life. A healthy adult requires 1–2 mg of thiamine daily, depending on the carbohydrate intake. Body’s reserves of thiamine are only 30–50 mg so any malnutrition condition lasting more than 3–4 weeks can cause complete depletion of the vitamin’s stores. Classically, WE is characterized by the sudden onset of a typical triad of symptoms: an altered mental state, ophthalmoplegia, and ataxia. However, this clinical picture can be seen in only one-third of patients. The onset of the disease may sometimes look completely different: heart failure with hypotension and tachycardia; gastrointestinal symptoms (abdominal pain and nausea); hypothermia due to the involvement of the posterior hypothalamus; deafness affecting the thalamus; epileptic seizures in case of enhanced activity of the glutamatergic system.The paper describes a clinical case of acute cerebellar ataxia that is apparently caused by Wernicke’s encephalopathy in a young woman

    Региоселективность раскрытия эпоксидного цикла окиси стирола этилендиаминами в различных средах

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    The results of styrene oxide epoxide cycle cleavage by diamines were summarized. The effect of solvent on regioselectivity in the reaction of N,N-diethylene diamine was studied. It was established that the ratio of products correlates well with polarity parameters ЕТ and АN of pure solvents.Обобщены результаты раскрытия эпоксидного цикла окиси стирола диаминами. Для N,N-диэтилэтилен-диамина исследовано влияние растворителя на региоселективность реакции. Установлено, что соотношение продуктов реакции хорошо коррелирует с параметрами полярности ЕТ и АN для чистых растворителей. Наибольшие отклонения наблюдаются для воды

    The significance of retained austenite in the high strength and plasticity of medium carbon Q&P steel

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    The Fe-0.44%C-1.8%Si-1.3%Mn-0.82%Cr-0.28%Mo steel treated by the quenching-partitioning partitioning process showed a product of strength and elongation of 30 GPa % with yield stress of 1350 MPa. Such a combination of high ultimate tensile strength and good ductility is attributed to a high portion of retained austenite (≥20%) transforming to martensite under tension. The high yield stress is provided by carbon supersaturation of austenite and a high dislocation density in this phas
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