81 research outputs found

    Preparation of γ-di-tertiary Glycols From the Esters of γ-keto Carboxylic Acids. II

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    Some Y-di-tertiary glycols have been prepared by the Grignard\u27s method from the Et esters of y-keto carboxylic acids

    Preparation of γ-di-tertiary Glycols From the Esters of γ-keto Carboxylic Acids. II

    Get PDF
    Some Y-di-tertiary glycols have been prepared by the Grignard\u27s method from the Et esters of y-keto carboxylic acids

    Cytogenetic findings in Serbian patients with Turner's syndrome stigmata

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    Cytogenetic findings are reported for 31 female patients with Turner's syndrome. Chromosome studies were made from lymphocyte cultures. Non-mosaicism 45, X was demonstrated in 15 of these patients, whereas only three were apparently mosaic. Eight patients showed non-mosaic and four patients showed mosaic structural aberrations of the X-chromosome. One non-mosaic case displayed a karyotype containing a small marker chromosome. Conventional cytogenetics was supplemented by fluorescence in situ hybridization (FISH) with an X-specific probe to identify the chromosomal origin of the ring and a 1q12-specific DNA probe to identify de novo balanced translocation (1;9) in one patient. To our knowledge, this is the first finding of karyotype 45,X,t(1;9) (cen;cen)/46,X,r(X),t(1;9)(cen;cen) in Turner's syndrome. The same X-specific probe was also used to identify a derivative chromosome in one patient

    Effect of Sex Hormones on Plasma Phospholipid Fatty Acid Composition in Intact Rats and Rats With Bilaterally Occluded Carotid Arteries

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    The effects of 8-days treatment with 17 alpha-estradiol (33.3 mu g/kg) and progesterone (1.7 mg/kg) on plasma lipids and fatty acid composition of plasma phospholipids were examined in intact (INT) and bilaterally common carotid arteries occluded (BCO) male Wistar rats. Significant decrease of triglyceride level was found in BCO rats after the estradiol treatment. Both hormones elevated proportion of 18:1n-7 fatty acid in INT, but they failed to have such an effect in BCO. Estradiol increased 22:5n-3 and total n-3 polyunsaturated fatty acids (PUFA) in intact, and decreased 18:2n-6 in BCO rats. Significantly lower level of total n-3 was found in progesterone-treated than in estradiol-treated BCO rats. Given that n-3 PUFA have many beneficial effects on cell and tissue function, while n-6 PUFA have mostly the opposite effects, estradiol, rather than progesterone, was seen to improve plasma lipids and phospholipids FA profiles in INT and BCO animals. Estradiol significantly elevated the estimated activity of Delta 9-desaturases and progesterone of Delta 5-desaturase in BCO group, with no effects in INT rats

    Antioxidant Enzymes in Blood of Women With Uterine Hyperplasia

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    The literature emphasizes the involvement of oxidative stress in the etiopathogenesis of many uterine diseases. Antioxidant system (AOS) represents the protective mechanism used by cells to neutralize overproduced reactive oxygen species (ROS) and prevent oxidative stress. We have previously shown that in gynecological patients with various diagnoses, the reproductive and other factors may be associated with antioxidant capacity and the ability to defend against oxidative damage. In this study, we examined the changes in expression of antioxidant enzymes (AOE): superoxide dismutases (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) in the blood of women with endometrial hyperplasia. Our results indicate that hyperplasia induces perturbance in oxidative balance, particularly in glutathione redox cycle enzymes

    Contribution to the research of oscillatory loads of sprung and unsprung masses in order to create conditions for laboratory tests of heavy motor vehicles

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    Introduction/purpose: Motor vehicles are complex dynamic systems due to spatial displacements, changes in the characteristics of components during their lifetime, a large number of influences and disturbances, the appearance of backlash, friction, hysteresis, etc. The aforementioned dynamic phenomena, especially vibrations, cause driver and passenger fatigue, reduce the lifetime of the vehicle and its systems, etc. Methods: In general, the movement of vehicles is carried out on uneven roads and curvilinear paths in the road. Not only do oscillatory movements cause material fatigue of vehicle parts, but they also have a negative effect on people's health. That is why special attention must be paid to the coordination of the mutual movement of the subsystems, and in particular, the vehicle suspension system, even at the stage of the motor vehicle design. For these purposes, theoretical, experimental or combined methods can be used. Therefore, it is very useful to have the experimental results of the oscillations of the vehicle subsystem in operating conditions, so the aim of this work was to use the movement of the 4x4 drive FAP 1118 vehicle in operating conditions (due to higher speeds - in road conditions) to define the conditions for testing oscillatory loads in laboratory conditions. Results:This is made possible by registering and identifying statistical parameters of registered quantities. Conclusion: Based on the measured data, the research can be programmed on shakers in laboratory conditions, and, at the same time, the size to be reproduced can be chosen as well

    Određivanje pKa vrednosti i korelacija sa strukturom p-supstituisanih trans-2,3-epoksi-4-okso-4-fenilbutanskih kiselina

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    The pKa values for a series of eight p-substituted trans-2,3-epoxy-4-phenyl butanoic acids (p-substituted trans-Ī²-aroylepoxyacrylic acids) have been determined potentiometrically in aqueous media at 25 Ā°C at an ionic strength of 0.1 mol/dm3 (NaCl). The transmission of polar effects from the substituents on the phenyl nucleus to the carboxylic group through the side chain involving a carbonyl group and an epoxide ring was investigated. The pKa values were correlated with structure using the Hammett, Taft and Yukawa-Tsuno approaches. The Hammett Ļ constant (0.34) was compared with analogue values for structurally similar acids.Određene su pKa vrednosti za seriju od osam p-supstituisanih trans-2,3-epoksi-4-okso-4-fenilbutanskih kiselina (p-supstituisanih trans-Ī²-aroilepoksiakrilnih kiselina). Vrednosti su određene potenciometrijski u vodenoj sredini na 25 Ā°C i jonskoj sili 0.1 mol/dm3 (NaCl). Proučavan je prenos polarnih efekata sa supstituenata na fenil jezgru ka karboksilnoj grupi kroz bočni niz koji sadrži karbonilnu grupu i epoksidni prsten. pKa vrednosti su korelisane sa strukturom primenom Hammett-ovog, Taft-ovog i Yukawa-Tsuno-ovog pristupa. Hammett-ova Ļ konstanta (0,34) je upoređena sa analognim vrednostima za strukturno slične kiseline
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