Ducks on the torus: existence and uniqueness

We show that there exist generic slow-fast systems with only one (time-scaling) parameter on the two-torus, which have canard cycles for arbitrary small values of this parameter. This is in drastic contrast with the planar case, where canards usually occur in two-parametric families. Here we treat systems with a convex slow curve. In this case there is a set of parameter values accumulating to zero for which the system has exactly one attracting and one repelling canard cycle. The basin of the attracting cycle is almost the whole torus.Comment: To appear in Journal of Dynamical and Control Systems, presumably Vol. 16 (2010), No. 2; The final publication is available at www.springerlink.co

Innovative practices in the system of higher education: impact, dynamics, challenges determining their development and M-plementation

This paper is an attempt to analyze the contemporary phenomena affecting higher education. The main impact and dynamics of the innovative practices in the system of higher education are studied. The authors consider the process of globalization, the changing of supply and demand in higher education, and changes in funding of higher education as factors that have the most significant impact on the functioning of the world market of educational services, and determine the development and implementation of the innovative practices in the higher education system at the present stage of its developmen

Knowledge structures and their representation in the language

The authors define and describe the components which build the structure of the frame "touch

Діастолічна функція лівого шлуночка та рівень N-кінцевого промозкового натрійуретичного пептиду у хворих на фібриляцію передсердь

In our study 100 consecutive non-valvular permanent atrial fibrillation patients with NYHA I – III heart failure, 43 - 86 years old (65 men and 35 women) were examined. Control group consisted of 30 patients with arterial hypertension and coronary artery disease matched by age, sex with basic group. Relationship of NT-proBNP with echocardiographic parameters of left heart were studied. Transthoracic echocardiography with tissue doppler measurements were performed on echocardiograph “SONOS7500”. For left ventricular filling pressure assessment ratio Em/Ea was used due to its diagnostic value in atrial fibrillation (regardless of left ventricular ejection fraction). Mean left ventricular filling pressure was increased in patients with heart failure: in atrial fibrillation group and controls as well. In comparison with controls atrial fibrillation group was more likely to have higher both systolic and diastolic left atrial square and volume. According to Em/Ea in 95% of patients with non-valvular atrial fibrillation high left ventricular filling pressure was observed, this testifies to diastolic dysfunction. This parameter correlated well with left atrial square and volume during systole and diastole. Correlation between NT pro-BNP level and NYHA class of  heart failure, left ventricular filling pressure was determined in patients with atrial fibrillation. Tissue doppler echocardiography makes it possible to diagnose left ventricular diastolic dysfunction in atrial fibrillation patients.Обследовано 100 пациентов с постоянной формой фиб­рилляции предсердий неклапанного генеза и хронической недостаточностью І – ІІІ функционального класса в возрасте 43 – 86 лет, из них 65 мужчин и 35 – женщин. Контрольную группу составили 30 пациентов с ИБС и ГБ, сопоставимых по возрасту и полу с основной группой. Изучали уровень N-проМНП и его связь с эхокардиографическими показателями функции левых отделов сердца у данной категории больных. Эхокар­диографическое исследование и тканевая допплерография проводились на аппарате «SONOS 7500». Для оценки давления наполнения левого желудочка рассчитывали соотношение Em/Ea, которое полностью сохраняет свое диагностическое значение (независимо от фракции выброса левого желудочка) при фибрилляции предсердий. Средний показатель давления наполнения левого желудочка был увеличен у больных с хронической сердечной недостаточностью, как при постоянной фибрилляции предсердий, так и на фоне синусового ритма. Было установлено достоверное увеличение размеров левого предсердия, его площадей и объемов в систолу и ди­астолу в группе пациентов с фибрилляцией предсердий в сравнении с группой контроля. По данным показателя Еm/Eaу 95% пациентов с фибрилляцией предсердий неклаппаного генеза выявлено повышение давления наполнения левого желудочка, что свидетельствует о нарушении диастолической функции. Данный пока­затель достоверно коррелировал с объемами и площадями левого предсердия в систолу и диастолу. Уста­новлена достоверная связь между уровнем N-проМНП и функциональным классом сердечной недо­ста­точности, уровнем давления наполнений левого желудочка у пациентов с фибрилляцией предсердий. Использование тканевого допплеровского исследования позволяет диагностировать нарушение диасто­лической функции левого желудочка при фибрилляции предсердий.In our study 100 consecutive non-valvular permanent atrial fibrillation patients with NYHA I – III heart failure, 43 - 86 years old (65 men and 35 women) were examined. Control group consisted of 30 patients with arterial hypertension and coronary artery disease matched by age, sex with basic group. Relationship of NT-proBNP with echocardiographic parameters of left heart were studied. Transthoracic echocardiography with tissue doppler measurements were performed on echocardiograph “SONOS 7500”. For left ventricular filling pressure assessment ratio Em/Ea was used due to its diagnostic value in atrial fibrillation (regardless of left ventricular ejection fraction).Mean left ventricular filling pressure was increased in patients with heart failure: in atrial fibrillation group and controls as well. In comparison with controls atrial fibrillation group was more likely to have higher both systolic and diastolic left atrial square and volume. According to Em/Ea in 95% of patients with non-valvular atrial fibrillation high left ventricular filling pressure was observed, this testifies to diastolic dysfunction. This parameter correlated well with left atrial square and volume during systole and diastole. Correlation between NT pro-BNP level and NYHA class of  heart failure, left ventricular filling pressure was determined in patients with atrial fibrillation. Tissue doppler echocardiography makes it possible to diagnose left ventricular diastolic dysfunction in atrial fibrillation patients

ASSOCIATION OF DNA REPAIR GENE POLYMORPHISM WITH CHROMOSOMAL ABERRATIONS IN THE BLOOD LYMPHOCYTES OF PATIENTS WITH LUNG CANCER

Analysis of association, between several DNA repair gene polymorphisms and the level of chromosomal aberrations (CAs) in lymphocytes was performed in two groups: a group of 215 patients with lung cancer and a control group of 152 donors. In the group patient with lung cancer the level of CAs shows a significant increase in the carrier of genotypes: XPD TG and XPD GG vs XPD TT. In the control group level of CAs shows a significant increase in the carrier of genotype ADPRT ТС vs ТТ

ANTIBODIES TO BENZO[A]PYRENE IN SERUM OF PATIENTS WITH NON-SMALL CELL LUNG CANCER

The features of immune response to chemical carcinogen benzo[a]pyrene (Bp) at the patients with non-small cell lung cancer (NSCLC) are investigated. The isotypical distinctions in formation of antibodies (Ab) to Bp at the men with NSCLC in comparison with healthy are revealed. There were more often observed the high levels of IgG Ab-Bp at the men with NSCLC. Thus risk of occurrence NSCLC grows almost in 2 times at high levels of Ab-Bp of a class G

АНТИТЕЛА К БЕНЗО[А]ПИРЕНУ, ЭСТРАДИОЛУ И ПРОГЕСТЕРОНУ У БОЛЬНЫХ РАКОМ МОЛОЧНОЙ ЖЕЛЕЗЫ В ПОСТМЕНОПАУЗЕ

The identification of women who are at high risk of developing breast cancer plays a key role in chemoprevention of breast cancer selective estrogen receptor modulators. purpose: To study specific immune responses to chemical carcinogens and sex steroid hormones associated with breast cancer in postmenopausal women. material and methods. Serum IgA-antibodies specific to benzo[a]pyrene, estradiol and progesterone were studied in 203 non-smoking healthy women and 469 non-smoking breast cancer patients (125 with ER– and 344 with ER+) using semi-quantitative enzyme immunoassay. results. The low levels of all three antibodies were revealed in 53.2 % of healthy donors, in 47.2 % of breast cancer patients with ER– and in 40.7 % of patients with ER+. The high levels of all three antibodies were found in 12.3 %, 18.4 % and 26.5 % of cases, respectively. In the studied groups, the levels of antibodies to estradiol and progesterone were correlated with the levels of antibodies to benzo[a]pyrene (rs=0.54–0.7, p<0.0001). Conclusion. Immunoassay of antibodies to exogenous and endogenous antigens could be useful for determining risk of developing ER+ breast cancer and preventing administration of tamoxifen and others selective modulators of estrogen receptors. Active immunization against exogenous chemical carcinogens could increase the levels of antibodies to endogenous steroids, thus stimulating breast cancer.Выявление женщин с высоким риском возникновения рака молочной железы является ключевым звеном в химиопрофилактике этого заболевания селективными модуляторами эстрогеновых рецепторов. Цель исследования – изучить специфические иммунные реакции на химические канцерогены и половые стероидные гормоны, ассоциированные с раком молочной железы, у женщин в постменопаузе. материал и методы. С помощью полуколичественного иммуноферментного анализа были изучены сывороточные антитела класса А, специфичные к бензо[a]пирену, эстрадиолу и прогестерону, у 203 здоровых некурящих женщин и 469 некурящих больных раком молочной железы (125 женщин с ER– и 344 с ER+  статусом опухоли). результаты. Низкие уровни всех трех антител были обнаружены у53,2 % здоровых женщин, 47,2 % больных раком молочной железы с ER– статусом опухоли и 40,7 % с ER+. Высокие уровни всех трех антител встречались в 12,3 %, 18,4 %, 26,5 % случаев соответственно. Во всех группах уровни антител к эстрадиолу и прогестерону коррелировали с уровнями антител к бензо[a]пирену (rs=0,54–0,7, p<0,0001). Заключение. Иммуноанализ антител к экзогенным и эндогенным веществам может быть полезным для определения риска возникновения ER+ рака молочной железы и превентивного назначения тамоксифена и других селективных модуляторов эстрогеновых рецепторов. Активная иммунизация против экзогенных химических канцерогенов может увеличивать уровни антител к эндогенным стероидам и таким образом стимулировать рак молочной железы

THE ASSOCIATION OF IMMUNE RESPONSE TO XENOAND ENDOBIOTIKS AND THEIRS BIOTRANSFORMATION ENZYME GENE POLYMORPHISM WITH CONGENITAL MALFORMATIONS OF THE FETUS

The correlation between immune response to benzo(a)pyrene and progesterone in combination with detoxification enzyme gene polymorphism (CYPIA2*1F and GSTTI) and the occurrence of congenital malformations of the fetus was revealed. It is shown that at high ratio of IgA-antibodies to benzo(a)pyrene and to progesterone in conjunction with the mutant allele of the gene CYPIA2*1F and the deletion genotype of the gene GSTTI chance of the reproductive pathology developing increases to 41 times