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1.
Phys Chem Chem Phys ; 25(37): 25526-25536, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37712871

RESUMEN

The spatial spin modulated structure (SSMS) of the cycloid type present in bulk BiFeO3 prevents the linear magnetoelectric effect. One way to influence this structure is to reduce the crystal size to the nanoscale. Various opinions are circulating in the literature about the effect of nanocrystal size on SSMS, and to investigate this issue, we used a number of methods, with zero-field NMR (ZF NMR) spectroscopy at the forefront. ZF NMR spectroscopy enables the direct observation of the distribution profile of local fields on iron atoms and defines the SSMS presence and its properties. We also examined the synthesized samples using XRD, TEM, and magnetometry. We conclude that SSMS persists as the nanocrystal size decreases to the cycloid period and less, becoming more harmonic. This is accompanied by the change of the anisotropy type from an "easy axis" to an "easy plane". Magnetic measurements show a significant increase in the saturation magnetization, remanent magnetization, coercivity, and exchange bias of nanocrystals with sizes close to the cycloid period, which is probably associated with incomplete spin compensation in the case of an incomplete cycloid period. Despite the fact that SSMS is retained in the samples with decreased size, the magnetic properties experience a sharp increase up to applicable values.

2.
Fiziol Zh (1994) ; 63(1): 84-90, 2017.
Artículo en Ucraniano | MEDLINE | ID: mdl-29975832

RESUMEN

The possible presence of the physiological relationship of erythrocyte antigens of the A, C, D, K alleles of the blood group systems in the examined horses of the Ukrainian selection with the spermogram major parameters has been demonstrated. It has been found that when investigating ad/bcm and dg/cgm alleles of the blood group system D in the stallions, there was the physiological tendency of the decrease in the semen activity on average less than 5 points; at the presence of ad/cgm, ad/d, ad/ de, ad/dk, bcm/d, bcm/de, bcm/dg bcm/dk cegm/cgm, cegm/d, cegm/dg, cegm/dk cgm/ceg, cgm/cgm, cgm/dg, cgm/dk de/ cgm, de/dk dg/di, dk/d, dk/de, dk/dk alleles the spermogram of the average quality with the activity of the semen on average from 5 to 7 points was obtained; at the presence of bcm/cgm, dg/dk, de/d, egm/d, cgm/de alleles high parameters of semen activity, more than 7 points, were received. The tendency of the increase in the semen concentration was revealed in the examined stallions having a/- allele of the blood group C. The possible decrease in the semen concentration in the stallions having a/-allele of the blood group K was shown. The alleles of the blood group system D had the highest statistical impact on the volume of the ejaculate, the activity, concentration and the number of pathological forms of semen, the correlation coefficient was 0,36; 0,31; 0, 43 and 0,27, respectively. At the same time it has been found out that the alleles of the blood group systems A,C and K had the coefficient of correlation with the examined parameters of the semen at the level of not more than 0,07.


Asunto(s)
Alelos , Antígenos de Grupos Sanguíneos/clasificación , Eritrocitos/química , Análisis de Semen/estadística & datos numéricos , Espermatozoides/fisiología , Animales , Antígenos de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/metabolismo , Recuento de Células , Expresión Génica , Caballos , Masculino , Análisis de Regresión , Recuento de Espermatozoides , Motilidad Espermática/fisiología , Espermatozoides/citología
3.
Tsitologiia ; 59(1): 45-52, 2017.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-30188102

RESUMEN

The article presents the results of the studies of cytotoxic effect of zearalenone and T-2 toxin on sperm of horses and bulls during incubation and after thawing according to the technology of sperm obtaining and cryopreservation in Kharkov. We first have shown in vitro toxic effects of different concentrations of zearalenone and T-2 toxin (from 0.5 to 0.01 mM) on the membrane stability, as well as quantitative and qualitative indicators of semen in stallions and bulls before and after freezing and thawing. It has been found that the biological activity of the native sperm in 1 h after addition of 0.5 mM zearalenone is not changed, and after thawing is reduced by 19.4 %, or 0.69 ball (P < 0.01) compared to control without toxin. T-2 toxin at a concentration of 0.5 mM reduced the activity of the native sperm after an hour of incubation by 0.59 ball (P < 0.01) and decreased it after thawing decreased by 60.28 %, or 2.14 ball (P < 0.001). 1 h of incubation with zearalenone at concentration of 0.25 mM did not affect the activity of the native sperm, but the activity after freeze­thaw deteriorated by 12.2 %, or 0.41 ball (P < 0.05). T-2 toxin at a concentration of 0.25 mM reduced activity of native sperm after 1 h exposure by 0.46 ball (P < 0.05), and after thawing spermatozoa degrade it by 1.77 ball (P < 0.001) compared to control without toxins. In our study, the lowest concentration giving a significant decrease in sperm parameters was 0.01 mM. The negative impact of zearalenone in such a dose on the native sperm was absent, and sperm after thawing only slightly reduced activity and perezhivayemost by 0.09 points and 0.27 hours, respectively. The simultaneous addition of zearalenone and T-2 toxin at the same dose of 0.01 mM resulted in a decrease in biological perezhivayemost and absolute indicator of native sperm perezhivayemost by 0.36 points and 0.64 hours (P < 0.05), respectively.


Asunto(s)
Criopreservación , Citotoxinas/farmacología , Espermatozoides , Toxina T-2/farmacología , Zearalenona/farmacocinética , Animales , Bovinos , Relación Dosis-Respuesta a Droga , Caballos , Masculino , Espermatozoides/metabolismo , Espermatozoides/ultraestructura , Factores de Tiempo
4.
Steroids ; 117: 112-119, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27693094

RESUMEN

Reaction of nitrosochlorides of natural monoterpene hydrocarbons (+)-3-carene and (-)-α-pinene with L-amino acids and their methyl esters results in stereoselective formation of terpene-amino acids hybrids, which belong to the series of α-substituted amino oximes. The reaction with an excess of racemic DL-amino acids and their derivatives induces partial resolution of the amino acid components and formation of the diastereomeric mixtures of the terpene-amino acids hybrids, with diastereomeric excess varying from 0 to 100%.


Asunto(s)
Aminoácidos/química , Monoterpenos/química , Monoterpenos Bicíclicos , Espectroscopía de Resonancia Magnética , Estereoisomerismo , Terpenos/química
5.
Ter Arkh ; 88(8): 59-66, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-27636929

RESUMEN

AIM: to analyze and summarize the data of the DIREG-2 study of the nonalcoholic fatty liver disease (NAFLD) register in Rostov-on-Don versus those in Russia. MATERIAL AND METHODS: The prospective disease registry study encompasses an epidemiologic, observational, cross-sectional, multicenter study estimating the prevalence of NAFLD in outpatients in Rostov-on-Don. A total of 3200 patients participated in this study. The investigators were 65 outpatient physicians. Epidemiological data were obtained during two patient visits to the research centers. RESULTS: The key result obtained from this study was the significantly higher prevalence of NAFLD in Rostov-on-Don than that in the general population (40.4 and 37.3%). In addition to the higher prevalence of NAFLD, there was also a higher spread of risk factors (RFs), such as abdominal obesity, female age of 45-55 years, and hyperlipidemia. CONCLUSION: The prevalence of NAFLD in the outpatients of Rostov-on-Don was 3.1% greater than that in Russia; this might be due to the significantly higher spread of some RFs (abdominal obesity, female age of 45-55 years, hyperlipidemia). The findings are undoubtedly necessary for the elaboration of measures for the primary and secondary prevention of NAFLD in Rostov-on-Don.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Calidad de Vida , Anciano , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/psicología , Pacientes Ambulatorios/estadística & datos numéricos , Prevalencia , Pronóstico , Factores de Riesgo , Federación de Rusia/epidemiología
7.
Lik Sprava ; (5-6): 82-5, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-18418926

RESUMEN

65 patients with a mild craniocereberal trauma have been observed. Medical examination included among general clinical methods the following methods: KT (MRT) of the brain, oculist examination including the observation of eye fundus. For objectification of a patient' complaints the authors used orientation and Galvestona's amnesia tests, feeling scale (psychological test), the table to determine the level of memory. Tests have been carried out on the first, tenth and thirty day of the treatment. Patients of the first group received in a complex treatment -pramistar, patients of the second group - piracetam. Patients of both groups noted considerable improvement during a complex treatment (disappearance of headache, dizziness and nausea) and at the same time patients receiving pramistar had better restoration of orientation and feeling. Pramistar was also more effective in patients with amnesia.


Asunto(s)
Conmoción Encefálica/tratamiento farmacológico , Nootrópicos/uso terapéutico , Piracetam/uso terapéutico , Pirrolidinas/uso terapéutico , Adolescente , Adulto , Atención/efectos de los fármacos , Conmoción Encefálica/psicología , Quimioterapia Combinada , Humanos , Memoria/efectos de los fármacos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Nootrópicos/administración & dosificación , Nootrópicos/efectos adversos , Piracetam/administración & dosificación , Piracetam/efectos adversos , Pirrolidinas/administración & dosificación , Pirrolidinas/efectos adversos , Resultado del Tratamiento
10.
Ross Fiziol Zh Im I M Sechenova ; 91(4): 400-7, 2005 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-15969440

RESUMEN

The hormonal level dynamics of hypophysis, thyroid gland and sex steroids was analyzed in respect to the puberty. Concentrations of gonadotropins and sex streroids were increased whereas concentrations of thyroid hormones was decreased. The amplitude of hypophysis and thyroid hormones were narrowed whereas the range of sex steroids was extended during the puberty. In early stages of puberty, the interhormonal correlations existed on some levels (hypophysis or peripheral gland), but in late stage the intersystem and polyhormonal relations were formed. Thyroid hormones play a leading role in sexual maturity regulation. The sexual maturity is prolonged, the variance of sexual stages being quite wide. The range of gonadotropin shifted to the left side in comparison with children in moderate latitudes.


Asunto(s)
Hipófisis/fisiología , Desarrollo Sexual , Testículo/crecimiento & desarrollo , Glándula Tiroides/fisiología , Adolescente , Niño , Hormonas/sangre , Humanos , Masculino , Hipófisis/crecimiento & desarrollo , Federación de Rusia , Glándula Tiroides/crecimiento & desarrollo
11.
Klin Lab Diagn ; (11): 35-8, 2004 Nov.
Artículo en Ruso | MEDLINE | ID: mdl-15646130

RESUMEN

The reserve potentialities of metabolism processes and the specificity of the functioning in the course of glucose-tolerance test made in virtually healthy residence of the European North were studied with respect to body weight. A slowed utilization of glucose, triglycerides and of free fatty acids due to an intensified insulin concentration was detected, which essentially affects, in persons with excessive weight, the nature of the mentioned changes and belongs to the risk category of diabetes mellitus and ischemic heart disease.


Asunto(s)
Glucemia/análisis , VLDL-Colesterol/sangre , Ácidos Grasos no Esterificados/sangre , Insulina/sangre , Triglicéridos/sangre , Adulto , Peso Corporal , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Federación de Rusia
14.
Probl Tuberk ; (4): 36-9, 2002.
Artículo en Ruso | MEDLINE | ID: mdl-12125251

RESUMEN

The essential oil of peppermint (Mentha piperita L.) has been found to have an in vitro pronounced and equal antimycobacterial effect in doses of 300 and 600 micrograms/ml, respectively. The use of its inhalations (upon 20-min heat evaporation into the room atmosphere for 2 months) as a supplement to combined multidrug therapy for pulmonary tuberculosis has indicated their significantly high positive effect in terms of abacillation (by 26.8 and 58.5% with doses of 0.01 and 0.005 ml/m3, respectively). This was followed by earlier positive X-ray changes in the lung and by attenuation of the intoxication syndrome. The findings suggest that peppermint essential oil may be used in combined multidrug therapy in patients with disseminated and infiltrative pulmonary tuberculosis.


Asunto(s)
Mentha , Fitoterapia , Tuberculosis Pulmonar/tratamiento farmacológico , Administración por Inhalación , Adolescente , Adulto , Anciano , Antituberculosos/uso terapéutico , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/aislamiento & purificación , Preparaciones de Plantas , Tuberculosis Pulmonar/microbiología
15.
Aviakosm Ekolog Med ; 36(5): 45-8, 2002.
Artículo en Ruso | MEDLINE | ID: mdl-12572124

RESUMEN

Lipid profile was studied in blood serum of 146 European northerns (trans-polar Nenets Autonomous district and Archangelsk). Monolayer chromatography was used to determine sphingomyelin (SP), phosphatidyl ethanolamine, phosphatidylcholine (PC), lisophosphatidylcholine, glycerophosphatides and phosphatide acides. The northerns were found to have very low concentrations of blood PC. At the same time, the NAD population have a little higher SP which may play an adaptive role in terms of the cell membrane function. The transpolar natives appear to possess an adaptive mechanism of increasing total cholesterol and reducing cholesterol of high-density lipoproteins, and activation of cholesterol esterification resulting in decrease in the free cholesterol fraction in serum.


Asunto(s)
Ésteres del Colesterol/sangre , Fosfolípidos/sangre , Adaptación Fisiológica/fisiología , Áreas de Influencia de Salud , Cromatografía en Capa Delgada , Esterificación , Femenino , Humanos , Masculino , Isquemia Miocárdica/sangre , Isquemia Miocárdica/etiología , Factores de Riesgo , Federación de Rusia
16.
Exp Appl Acarol ; 24(2): 145-58, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11108395

RESUMEN

Chemical compositions of ethereal extracts of the body surface of unfed male and female Ixodes persulcatus ticks (Acari: Ixodidae) were studied by gas chromatography using mass-spectrometric detection. More than 100 different organic compounds were detected. The predominant components were saturated fatty hydrocarbons, saturated and unsaturated fatty acids, aldehydes, squalene, cholesterol and cholesterol derivatives. A number of compounds found in I. persulcatus are known as components of pheromones or constituents of dermal gland secretions in tick species of the genus Amblyomma: nonanoic acid, saturated fatty acids having from 14 to 16 carbons, and squalene. Saturated fatty aldehydes have not been reported previously as body surface components of hard ticks. Substituted phenols were not found in the extracts, although they are known as common components of sex and attraction-aggregation-attachment pheromones in Amblyomma ticks. With a few exceptions (henicosanal, 2,4-holestadiene and two unidentified cholesterol derivatives), there was no marked difference in composition of surface components between male and female I. persulcatus. The possible role of the different chemical groups in communication between I. persulcatus ticks is discussed.


Asunto(s)
Lípidos/análisis , Atractivos Sexuales/análisis , Garrapatas/química , Aldehídos/análisis , Animales , Colesterol/análogos & derivados , Colesterol/análisis , Ácidos Grasos Insaturados/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos/análisis , Masculino , Federación de Rusia , Escualeno/análisis
18.
Ross Fiziol Zh Im I M Sechenova ; 84(5-6): 521-6, 1998.
Artículo en Ruso | MEDLINE | ID: mdl-9785419

RESUMEN

Correlation analysis of the findings suggests that in March an increase of the glucose level is induced by the thyroid hormones in humans living on Spitsbergen Archipelago. A liability of functional interactions among thyroid hormones, insulin, and glucose seems to be caused bias alterations in the air temperature as contrast to photoperiodicity.


Asunto(s)
Glucemia/metabolismo , Insulina/sangre , Estaciones del Año , Hormonas Tiroideas/sangre , Adulto , Regiones Árticas , Homeostasis , Humanos , Masculino , Persona de Mediana Edad , Páncreas/metabolismo
19.
Ross Fiziol Zh Im I M Sechenova ; 84(1-2): 119-24, 1998.
Artículo en Ruso | MEDLINE | ID: mdl-9612867

RESUMEN

A complex effect with photo-periodic components and depending on the duration of stay on Shpitzbergen Archipelago of people working there, was revealed in respect to the serum concentration of Ig A, G, M. The monocytes, autoantibodies, and circular immune complexes were increased, whereas lymphocytes, T-cells, and natural killers were decreased in winter time.


Asunto(s)
Adaptación Fisiológica/inmunología , Adulto , Animales , Regiones Árticas , Recuento de Células Sanguíneas , Homeostasis/inmunología , Humanos , Inmunoglobulinas/sangre , Inmunoglobulinas/inmunología , Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Neutrófilos/inmunología , Fotoperiodo , Estaciones del Año , Factores de Tiempo
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