37 research outputs found

    THE DEPENDENCE OF THE CHAIN BRANCHING DEGREE ON MOLECULAR WEIGHT: FRACTAL ANALYSIS

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    The fractal analysis methodology allows the clear structural identification of both chemical and physical factors controlling a chain branching degree. The effective number of branching centers per one macromolecule m is controlled by four factors: polymer molecular weight, MW, maximal “chemical” density of reactive centers, cch, dimension of non-screening surface of macromolecular coil, du, and its fractal dimension, D. The presented research allows the determination of the critical value, Dcr = 1.10, the lower of which branching degree is equal to zero (i.e., branching does not occur

    INTERRELATION BETWEEN LUNGS FUNCTiONAL PARAMETERS AND CONDiTiON OF BONE TISSUE AT THE TERMINAL PULMONARY PATHOLOGY

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    The aim of this study was to evaluate the condition of mineral density of bone tissue at the terminal pulmonary pathology, to determine correlations between lungs functional parameters and. pre-transplantation bone mass. Materials and methods: we realized retrospective analysis of 74 case histories of patients with terminal pulmonary pathology, waiting for lung transplantation. MDBT in lumbar segment of spine (L2—L4) and. femoral neck (FN) was evaluated, with help of double-energy X-ray absorptiometry (Hologic). Function of external respiration was researched, gasometry and 6-minutes walking test were realized, in all the patients. Results: osteopenic syndrome in any zone of interest was registered in 69 % of patients. Normal indices of MDBT both in L2—L4 and. in FN were registered only in 11 % of patients. On our data the indices of T-criterion (both, in L2—L4 and. in FN) had. direct relation with, body weight index (BWI) and. total fatty mass. Direct correlation between MDBT, volume of forced expiration for 1 second. (FEV) (r = 0,49, p < 0,05 in L2—L4 and. r = 0,52, p < 0,05 in FN) and. indirect correlation with, total lungs capacity (TLC) (r = —0,53, p < 0,01) with residual lungs volume (RV) (r = —0,48, p < 0,05) only in FN. We revealed, reliable negative interrelation, of MDBT only with pCO2 of arterial blood (r = —0,54, p < 0,01 in L2—L4 and r = —0,48, p < 0,05 in FN). There were no reliable correlation between DLCO, 6-minutes walking test and. MDBT both in L2—L4 and. in FN. 11% of patients had. atraumatic fractures of different localization. Conclusion: thus, osteoporosis is sufficiently frequent system, manifestation, in patients with, different terminal pulmonary pathology in pre-transplantation period. Worsening of lungs functional parameters, low BWI and. decrease of total fatty mass can be strong predictors of osteoporosis at the serious respiratory pathology

    Особенности ранней диагностики пигментной глаукомы с псевдонормальным давлением после радиальной кератотомии (клинический случай)

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    The article describes a clinical case of diagnostics and diagnosis of pigmentary glaucoma with pseudo-normal pressure in a patient who had previously underwent radial keratotomy (RKT).This case is interesting in that the detection of pigmentary glaucoma can be significantly complicated by a falsely low level of intraocular pressure (IOP) in the myopic eye after previous RKT and secondary hypermetropic shift, combined with the difficulty of an in-depth ophthalmoscopic assessment of the state of the optic nerve head in myopia, as well as perimetric study due to keratotomy scars. Tonometric IOP readings in such eyes should be considered carefully and supplemented with examination of other characteristic clinical signs of pigmentary glaucoma. This would help establish the diagnosis early and timely prescribe pathogenetic treatment.В статье описывается клинический случай диагностики и выявления пигментной глаукомы с псевдонормальным давлением у пациента после ранее выполненной радиальной кератотомии (РКТ).Данный случай интересен тем, что ложнозаниженный уровень внутриглазного давления (ВГД) в миопическом глазу после ранее проведенной РКТ и сформировавшегося вторичного гиперметропического сдвига в сочетании с затруднением углубленной офтальмоскопической оценки состояния диска зрительного нерва при миопии, а также периметрического исследования из-за кератотомических рубцов, способен значительно затруднить выявление пигментной глаукомы. Следует относиться с осторожностью к показателям тонометрического уровня ВГД в подобных глазах, выявляя другие характерные для пигментной глаукомы клинические признаки. Это позволит вовремя выставить диагноз и своевременно назначить патогенетическое лечение

    Comprehensive patterns of comorbidity: copd and depression

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    Introduction: Data on the prevalence of psychopathological disorders in the exacerbation of chronic obstructive pulmonary disease (COPD) are very heterogeneous. COPD and depression have common predisposing factors. The aim: The aim of the research is to conduct a comprehensive assessment of the e»ect of paroxetine on the level of depressive disorders in the exacerbation of severe degree COPD in women. Materials and methods: The study included patients with severe degree COPD and depressive disorder. A step-by-step test, dynamometry of muscular strength of muscle groups and calculation of the percent ratio of muscular strength to mass were performed for all patients, and the strength of the respiratory muscles was measured. To assess the level of depression, the HADS questionnaire and the CES-D self-questionnaire were used. Assessment of the severity of the patient’s condition was conducted according to the Hospital Alert and Depression Scale (HADS). Results: In exacerbation of severe COPD, the level of depression in patients correlates with the severity of the main criteria: FEV1, the 6-minute step test distance, oxygen saturation after the 6-minute step test, expiratory pressure in the oral cavity. Conclusions: Upon the synchronization of the standard therapy, the level of depression in patients with exacerbation of severe COPD e»ectively decreases. Paroxetine is a valid choice in the comprehensive treatment of COPD. According to the data of evidence-based medicine, the medication demonstrates high eÈciency and favorable safety pro le, without exerting a negative e»ect on COPD, which is of key signi cance in the combined pathology treatment

    ИССЛЕДОВАНИЕ ВЛИЯНИЯ ОРГАНИЧЕСКИХ ВОЛОКОН НА ТЕРМОСТОЙКОСТЬ ПОЛИАРИЛАТА

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    The process of thermal destruction of organic plastics based on polyarilate was investigaed. Thermal resistant of the developed materials was experimentally meashured. According to the thermal analysis mechanism and kinetic parameters of thermal destruction process of organic plastics using by Coates-Redfern method were identified Structural transformations at the molecular level in organic plastics were studied using by IR-spectroscopy.  Исследован процесс термического разложения органопластиков на основе полиарилата. Экспериментально измерена термостойкость разработанных материалов. По данным термического анализа определены механизм и кинетические параметры процесса термической деструкции полиарилата и органопластиков на его основе с использованием метода Коатса-Редферна. Структурные превращения на молекулярном уровне в органопластиках исследованы методом ИК-спектроскопии.

    Оптимизация параметров переработки органопластиков на основе фенолформальдегидной смолы

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    The influence of processing regimes on strength of organic plastics based on phenol-formaldehyde resin reinforced with organic fiber is investigated, through of mathematical planning of the experiment, in the article. It is shown that the composition is characterized by the greatest strength at a temperature T = 160–173 °C and a pressure P = 27–34 MPa. A mathematical model that adequately describes the process under investigation is obtainedИсследовано влияние режимов переработки на прочность органопластиков на основе фенолформальдегидной смолы, армированной органическим волокном с помощью математического планирования эксперимента. Показано, что композиция характеризуется наибольшей прочностью при температуре Т = 160–173 °С и давлении Р = 27–34 МПа. Получена математическая модель, адекватно описывающая исследуемый процес
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