ABSTRACT
We studied the neutron quantum states in the potential well formed by the Earth's gravitational field and a horizontal mirror. The estimated characteristic sizes of the neutron wave functions in two lowest quantum states correspond to their expectations with an accuracy of ≈25 %. The spatial density distribution in a standing neutron wave above a mirror was measured for a set of a few lowest quantum states. A position-sensitive neutron detector with an extra high spatial resolution of 1 µm to 2 µm was developed and tested for this particular task. Although this experiment was not designed or optimized to search for an additional short-range force, nevertheless it allowed us to slightly improve the published boundary in the nanometer range of characteristic distances. We studied systematical uncertainties in the chosen "flow-through" method as well as the feasibility to improve further the accuracy in this experiment.
ABSTRACT
The impact of a 4-week course of lovastatin (mevacor) therapy on platelet function was examined in 26 patients with coronary heart disease concurrent with hypercholesterolemia (the baseline plasma cholesterol level was 250 mg% or more). The agent was given in a daily dose of 20-40 mg. The agent in this dose was found to have no action on the thromboxane-prostacyclin balance in plasma, on the degree of ADP-induced aggregation and lipid peroxidation in platelets, phospholipid composition and levels of ester-bound cholesterol in platelet membranes. Free cholesterol tended to increase at the end of the 4th week of treatment. Despite the effective reduction of plasma levels of total and LDL cholesterols whose action on platelets is well known, there was no estimated decrease in the activity of platelets during lovastatin therapy.
Subject(s)
Blood Platelets/drug effects , Coronary Disease/blood , Hypercholesterolemia/drug therapy , Lovastatin/pharmacology , Adult , Cholesterol/blood , Coronary Disease/complications , Humans , Hypercholesterolemia/complications , Lovastatin/administration & dosage , Male , Middle Aged , Platelet Aggregation/drug effects , Time FactorsABSTRACT
The parameters of the structure and function of platelet membranes were examined in 30 patients with unstable vasospastic angina in relation to the outcome of the disease (myocardial infarction stabilization or development). The fractions of phospholipids (lysophosphatidylcholine, phosphatidylserine, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine), the levels of platelet membranous free and esterified cholesterol, plasma malonic dealdehyde and thromboxane B2, the activity of platelet superoxide dismutase and catalase were determined. The exacerbation of vasospastic angina was found to appear as accumulation of cholesterol (mainly of its fraction), an increase in platelet membranous levels of phosphatidylcholine, phosphatidylethanolamine and sphingomyelin, accumulation of malonic dealdehyde. These changes were more profound in cases with subsequent myocardial infarctions. There were differences in the dynamics of the examined parameters in relation to the outcome of the disease.
