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Reference intervals for normal concentrations in blood of vitamins B1, B2, E, D, retinol, beta-carotene, and folic acid were determined from a selected sample of people attending a Health Examination Center or being examined in occupational health services in France. This reference sample consisted of 362 men and women, ages 18 to 44 years, selected according to the main variation factors known for the vitamins studied: consumption of tobacco and alcohol, ponderal index (relating height and weight), use of drugs and oral contraceptives, and past history of surgical or medical treatment. Reference intervals were determined for each sex. Vitamin B1 (erythrocyte transketolase activity), plasma retinol, and folic acid values in whole blood are significantly higher in men than in women (p less than 0.001), but vitamin B2 (activation of erythrocyte glutathione reductase) and plasma beta-carotene values are significantly higher in women (p less than 0.001 and less than 0.01 respectively). Dietary intake of vitamins produced no significant displacement of the reference values. For each vitamin we discuss the other major sources of variation factors and the usual values reported in the literature.

130 patients with recent transmural myocardial infarction were studied in order to evaluate changes in left ventricular compliance. Left heart catheterization and cineangiographic left ventriculography were performed. The modulus of chamber stiffness (K) was determined from the slope of the linear relation between volume stiffness (dP/dv) and pressure; the modulus of muscle stiffness was evaluated by the Laird index (asymptotic slope of logP vs log V). Patients were divided in 3 groups: Group A included 5 patients studied before and after myocardial infarction who experienced an increase in the modulus of chamber and muscle stiffness after infarction. Group B included 10 patients who were studied at the onset of infarct and 15 days later: this group demonstrated changes in LV compliance with, most often a rightwardshift of P-V curve in anterior infarct and inversely a leftward shift in posterior infarction. The 115 patients of Group B are roughly equally distributed in the areas of normal, increased or decreased compliance. Any correlation was found between the extent of asynergy and changes in modulus of chamber stiffness. However, ejection fraction or VCF were higher in patients with a reduction of compliance than in patients with an increase of compliance.