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101.
MG Tvorogova VP Lupanov EIu Nuraliev TM Za?tseva VV Kukharchuk VN Titov 《Canadian Metallurgical Quarterly》1998,70(8):17-21
AIM: Evaluation of effectiveness of hypolipidemic action of probucol in doses 500 and 1000 mg/day and comparison of probucol blood concentrations on the treatment month 3 and 6. MATERIALS AND METHODS: Probucol (Akrikhin, Russia) was given to 41 patients with primary hypercholesterolemia in a dose 500 mg/day. 3 months later the patients were divided into two groups. Group 1 patients exhibited a > 10% decrease in cholesterol levels and continued to take probucol in the dose 500 mg/day. Group 2 patients were crossed over to higher cholesterol dose--up to 1000 mg/day. Lipids levels were measured by enzyme tests, apoproteins--by immunoturbidimetry and immunodiffusion, probucol concentrations--by high-performance liquid chromatography. RESULTS: After 3 months of treatment, cholesterol lowered by 14.3 and 9.2% in groups 1 and 2, respectively. After 6 months, by 19.7 and 12.9%, respectively. Probucol concentrations in blood were higher after 6 months of treatment than after 3 months in both groups. No significant differences existed between the groups by probucol concentrations in 3 and 6 months. CONCLUSION: Hypolipidemic effect of probucol depended on the individual features of lipoproteins metabolic disorders rather than the drug blood concentration. Larger probucol doses fail to reduce cholesterol further. 相似文献
102.
A method for determining whether structures distributed along a cell's membrane represent a random spatial distribution is presented in this paper. Two three-dimensional (3-D) images are acquired from one cell by wide-field digital imaging of cells which have been labeled with two different fluorescent antibodies. Prior to spatial analysis, a constrained regularized least squares restoration of the images is performed. This is followed by registration via fiducial markers (dual-labeled beads). A deformable model is then used to map data near the surface to the surface. Finally, each resulting data set is analyzed to determine whether it is spatially random. To do this, we generalize the test for complete spatial randomness of points in a plane, to test voxels distributed along a voxelized membrane in three dimensions. We also test whether the distribution of one protein is independent of the distribution of a second protein. The method is applied to compare the distribution of the protein kinase C to that of vinculin. Vinculin is a protein which anchors intracellular filaments to the cell's plasma membrane. It is also used as a (sparse) membrane marker for the deformable model. Protein kinase C facilitates molecular motors inside the cell. These may be associated with actin and myosin filaments. 相似文献
103.
An increasing body of evidence has linked infections to atherosclerosis and thrombosis. Herpesviruses cause atherosclerosis in experimental animals. Herpesviruses can also be detected in atherosclerotic lesions in humans. Cytomegalovirus may play a role in arteriosclerosis in transplanted hearts, and this virus, together with tumor suppressor protein p53, can be found in restenosis lesions following angioplasty. Chlamydia pneumoniae and dental infections are associated with coronary heart disease in cross-sectional and longitudinal studies, and preceding respiratory infections are associated with ischemic stroke. Infections may favor formation of atherosclerosis and thrombosis by elevation of blood levels of fibrinogen, leukocytes, clotting factor, and cytokines and by alteration of the metabolism and functions of endothelial cells and monocyte macrophages. Low-grade infections may also be one of the causes of the inflammatory reaction observed in atherosclerotic lesions and acute ischemic symptoms, reflected in elevated levels of C-reactive protein. These observations warrant further studies in this field. 相似文献
104.
Skating is a favourite sport in the Netherlands. Injury data on skating were collected from the emergency departments of 6 hospitals in the province of Friesland in the Netherlands during the Eleven Cities ice skating marathon over 200 kilometers in January 1997, with 16,688 participants. Among a total of 55 fractures, the maxillofacial skeleton had a relative high fracture frequency (n = 7; 13%), especially the zygomatic complex (n = 6); one patient had a mandibular fracture. An innocent-looking black eye, unilateral numbness of the upper lip and malocclusion following a skating accident merit full medical attention. 相似文献
105.
SM Liapunov IF Seregina OI Okina VV Golubchikov IV Kislova AA Kistanov EP Shevchenko NM Sorokina 《Canadian Metallurgical Quarterly》1998,(12):37-44
The authors specified methods to detect lead in biologic materials. The quality control covered use of Russian and foreign standard samples, the results proved to agree. Lead was detected by AAS technique (direct and flow-type variants with preliminary concentration of lead) and ELRA method. The authors determined measurement limits sufficient for analysis of complex biologic materials. The measurement range for lead varied from 0.002 mg/kg (plants) to 3,000 mg/kg (soil); the range of serum lead levels was < 0.5-39 mg/dl. 相似文献
106.
Evtodienko YuV VV Teplova J Duszyński K Bogucka L Wojtczak 《Canadian Metallurgical Quarterly》1994,15(6):439-446
The effect of Ca2+ on energy-coupling parameters of Ehrlich ascites carcinoma was studied in digitonin-permeabilized cells. In nominally Ca-free medium the permeabilized cells respond to the addition of ADP by increased oxygen uptake with externally added respiratory substrates (succinate or pyruvate), decrease of the mitochondrial membrane potential (delta psi) and alkalinization of the medium. This typical behaviour is drastically changed if Ca2+ is added. The subsequent addition of ADP induces neither State 3 respiration, nor decrease of delta psi, nor alkalinization of the medium, indicating a complete block of ATP synthesis. These effects are produced by both a single pulse of 100 microM Ca2+ and a preincubation for 2 min with 0.4-1.0 microM Ca2+. Preincubation of the cells with glucose or deoxyglucose prior to permeabilization makes them sensitive to Ca2+ concentrations as low as 0.3 microM. In view of the previous finding that glucose and deoxyglucose produce an increase of cytoplasmic [Ca2+] in Ehrlich ascites cells [Teplova VV. Bogucka K. Czyz A. Evtodienko YuV. Duszyński J. Wojtczak L. (1993) Biochem. Biophys. Res. Commun., 196, 1148-1154; Czyz A. Teplova VV. Sabala P. Czarny M. Evtodienko YuV. Wojtczak L. (1993) Acta Biochim. Polon., 40, 539-544], the present results suggest that cytoplasmic Ca2+ plays a crucial role in the Crabtree effect. 相似文献
107.
108.
WM Novick AT Gurbuz DC Watson VV Lazorishinets AN Perepeka I Malcic B Marinovic BS Alpert TG DiSessa 《Canadian Metallurgical Quarterly》1998,66(5):1533-1538
BACKGROUND: Closure of a large ventricular septal defect (VSD) in children with elevated pulmonary vascular resistance is associated with significant morbidity and mortality. Pulmonary hypertensive episodes continue to be a major cause of postoperative morbidity and mortality. We designed a fenestrated flap valve double VSD patch in an effort to decrease the morbidity and mortality associated with the closure of a large VSD with elevated pulmonary vascular resistance. METHODS: Eighteen children (mean age, 5.7 years) with a large VSD and elevated pulmonary vascular resistance (mean, 11.4 Wood units) underwent double patch VSD closure using moderately hypothermic cardiopulmonary bypass and cardioplegic arrest. The routine VSD patch was fenestrated (4 to 6 mm) and on the left ventricular side of the patch, a second, smaller patch was attached to the fenestration along its superior margin before closure of the VSD. RESULTS: All children survived operation and were weaned from inotropic and ventilator support within 48 hours postoperatively. Postoperative pulmonary artery pressures were significantly lower than preoperative values. One child died 9 months postoperatively. CONCLUSIONS: Closure of a large VSD in children with elevated pulmonary vascular resistance can be performed with low morbidity and mortality when a flap valve double VSD patch is used. 相似文献
109.
Commercially available serotonin-type 3 (5-HT3) receptor antagonists (ondansetron, granisetron, and tropisetron) have shown no clinically significant adverse effects on the cardiovascular system. In the dose-ranging evaluation of dolasetron, computer-generated ECGs revealed clinically asymptomatic prolongations of ECG intervals. We performed a clinical trial in which the possible changes in ECG intervals following a single 3-mg i.v. injection of granisetron and an injection of either doxorubicin or epirubicin were registered using computerized ECG analysis in cancer patients. A total of 30 patients who were designated to receive 3 mg granisetron i.v. for the prophylaxis of emesis induced by doxorubicin or epirubicin were entered into the study. Computer-generated ECG tracings were obtained before treatment, following the injection of 3mg granisetron, and immediately after doxorubicin or epirubicin injection. The mean PR interval duration increased from 160 to 166 ms after granisetron infusion (P=0.02). Doxorubicin and epirubicin did not potentiate this change. There was no statistically significant change in cardiac rhythm, QRS duration, or QTc intervals. The observed minor changes in the PR time following i.v. injection of granisetron do not seem to be of clinical relevance. 相似文献
110.