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71.
Orbetzova MM Shigarminova RG Genchev GG Milcheva BA Lozanov LB Genov NS Zacharieva SZ 《Folia medica》2003,45(3):21-25
INTRODUCTION: Polycystic ovary syndrome (PCOS) is associated with higher risk of developing cardiovascular diseases including higher incidence of hypertension later in life. Absence of circadian blood pressure fluctuations is considered as a marker of pre-hypertensive state and correlates highly with target organ damage in hypertension. AIM: Characterization of the circadian blood pressure rhythms as well as comparison of the results from the clinical measurements and Holter-monitored blood pressure data in women with PCOS. MATERIALS AND METHODS: The study comprised 35 women (mean age 22.6 +/- 5.9 years, mean BMI 31.4 +/- 7.1 kg/m2) with proven diagnosis. 24-hour ambulatory Holter-monitoring using Oscar device (Sun Tech Medical Instruments, USA) was performed in parallel with clinical measurements of blood pressure. RESULTS: There were 25.7% of the subjects diagnosed with hypertension according to the criteria of ambulatory monitoring observing discrepancy with the criteria for normal clinically measured blood pressure in 7 cases (20%). The "white coat" effect was observed in 11.4%. Physiological nocturnal drop in the systolic pressure was not observed in 51.4% of the patients and in the diastolic pressure - in 22.9% of the cases. CONCLUSIONS: The results confirm the advantages and the importance of the 24-hour monitoring as a diagnostic and predictive method for assessment of blood pressure alterations even in the absence of overt hypertension. PCOS is characterized by higher incidence of unstable blood pressure that is an additional risk factor for further development of cardiovascular diseases in this relatively young age group. 相似文献
72.
Scientific Research Institute for Transplant Science and Artificial Organs, Moscow. Translated from Meditsinskaya Tekhnika, No. 1, pp. 28–31, January 1990. 相似文献
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V. I. Shumakov N. K. Zimin A. A. Drobyshev M. N. Petukhova S. V. Agafonov G. P. Itkin 《Artificial organs》1987,11(1):16-19
Experiments with the Poisk model of an ellipsoid artificial heart are reported. With a modified model of the diaphragm type made from polyurethane, calves survived for a mean of 55 days, with a maximum survival of 3 months. With adequate anticoagulation therapy, no thrombogenesis was observed in the blood chamber (except for the inlet valves); a low level of plasma hemolysis was observed postoperatively. Good correlation was demonstrated between the stroke volume and left and right atrial pressures. Changes in the blood coagulation indices are reported. Implantation of a clinical variant of this prosthesis into human cadavers demonstrated no difficulties in placing the heart in the pericardial cavity. Developmental efforts are continuing. 相似文献
80.
Nikolay P Nikitin Klaus K A Witte Simon D R Thackray Ramesh de Silva Andrew L Clark John G F Cleland 《Journal of the American Society of Echocardiography》2003,16(9):906-921
OBJECTIVE: Quantitative 2-dimensional color Doppler tissue imaging is a new method to reveal impairment of left ventricular (LV) and right ventricular (RV) longitudinal function, which is a potential marker of early myocardial disease. The aim of this study was to obtain normal values for atrioventricular annular and regional myocardial velocities using this method. METHODS: A total of 123 healthy patients (age range: 22 to 89 years) underwent echocardiography including color Doppler tissue imaging using a scanner (Vivid 5, GE Vingmed, Horten, Norway) with postprocessing analysis (Echopac 6.3, GE Vingmed). Regional myocardial velocities were measured at 12 LV segments in 3 apical views and 2 segments of the free RV wall. Mitral annular velocities from 6 sites, and tricuspid annular velocities at its lateral site, were also assessed. At each site, systolic (S(m)), early diastolic (E(m)), and late diastolic (A(m)) velocities were measured, and the E(m)/A(m) ratio was calculated. RESULTS: Patients were classified into 4 groups aged 20 to 39, 40 to 59, 60 to 79, and >/=80 years. Mitral annular velocity and regional LV myocardial S(m) and E(m) progressively decreased with age. A(m), whereas low in the youngest age group, increased significantly in patients more than 40 years of age. The E(m)/A(m) ratio gradually declined with aging. There were no differences between age groups in S(m) measured at the tricuspid annulus and free RV wall, but the pattern of age-related changes of diastolic velocities and E(m)/A(m) ratio was the same as in the LV. Slight but significant sex-related differences were observed in middle-aged groups. The intraobserver and interobserver reproducibility was highest for atrioventricular annular velocities. CONCLUSIONS: A progressive decrease in S(m) reveals a decline in longitudinal systolic LV function with age, whereas systolic RV function remains unaffected. Atrioventricular annular velocity and regional E(m) decrease with aging in both ventricles, suggesting a deterioration in the diastolic properties of the myocardium, whereas A(m) increases from middle age implying a compensatory augmentation of atrial function. The study results can be used as reference data for the quantitative assessment of longitudinal LV and RV function in patients with cardiac disease. 相似文献