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991.
992.
The fact that an increased blood insulin level is observed in patients with coronary artery disease (CAD) confirms the hypothesis that insulin promotes the development of atherosclerosis. The low high-density lipoprotein (HDL) concentration observed in such patients may contribute to alteration in reverse cholesterol transport and promote the accumulation of sterols in vascular tissue. We examined the effect of insulin (20−1000μUmL−1) on cholesterol efflux into HDL3 particles from human blood monocyte/macrophages and rat peritoneal macrophages preloaded with labelled cholesterol esters, and the influence of insulin on the accumulation of sterols by rat liver cells and HepG2 cell line in vitro models. Insulin at concentrations up to 250μUmL−1 inhibited the efflux of cholesterol from rat macrophages and promoted high uptake of sterols by both types of hepatic cells. Pharmacological concentrations higher than 250μU mL−1 exerted the opposite effect. In the case of human macrophages, an insulin concentration of 20μUmL−1 increased cholesterol removal, whereas 100−200μU mL−1 insulin inhibited cholesterol removal from cells, and very high concentrations (>350μUmL−1) again increased cholesterol removal. We have shown that insulin excess counteracts the beneficial effects of HDL in removing cellular cholesterol and, therefore, may promote development of atherogenesis.  相似文献   
993.
994.
995.
996.
A study of 585 patients with acute myocardial infarction (285 with and 300 without cardiac arrest) showed the two groups to differ significantly in terms of clinical, laboratory and electrocardiographic findings. Resuscitation effectiveness depended upon the form of cardiac arrest (chi 2 = 209.25; p less than 0.001). A stable resuscitation effect (survival within and beyond 28 days after the onset of acute myocardial infarction) was achieved in 78.4% of cases of primary ventricular fibrillation, 24.0% of cases of secondary ventricular fibrillation, and 4.9% of asystolia cases. All cases of electromechanical dissociation were fatal. Long-term follow-up showed that 17.3% of patients with cardiac arrest and 21.9% of patients without cardiac arrest died over 4 years (p greater than 0.05).  相似文献   
997.
998.
In experiments on white male mice there was studied the influence of piracetam (250-300 mg/kg) on the analgesic effect of ligands of different types of opioid receptors (morphine, 7.5 mg/kg, DADLE, 7.5 mg/kg, pentazocine, 15 mg/kg) and also on the action of morphine concerning the cardiovascular system and respiration. Piracetam was shown to possess the antagonistic properties with respect to some effects of morphine, however they are not of the universal character and do not depend on the interaction with a certain type of opioid receptors.  相似文献   
999.
1000.
Under examination there were 198 patients with severe mechanical traumas at their admission to the clinic and on the 1st, 3d, 7th, 14th and 21st days by 25 hemocoagulation parameters determined by common present-day methods. The direction and degree of hemocoagulation alterations were found to be related with the severity of trauma, blood loss volume and severity of shock. It was shown that disseminated intravascular coagulation (DIC) of the II and III degree was developing in critical associated traumas, massive blood loss and severe shock in acute period of the disease. The acute form of DIC with reactive fibrinolysis was established in the lethal outcome during the shock period, latent (slow) DIC with local fibrinolysis took place in lethal outcomes in later periods.  相似文献   
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