An electronic frequency shifting stethoscope for heart sounds

The predominating energy in the normal heart sounds has been found to be at frequencies below the normal hearing threshold. Because it was felt that significant clinical information was likely to be present at those frequencies, an instrument was designed and fabricated which would frequency shift the entire heart sound into the middle of the auditory frequency range. Clinical testing showed that changes were readily detected in a monitoring situation, and that use of the instrument was both simple and easy to learn.     

Ketonaemia in Uncontrolled Diabetes Mellitus

Blood ketone bodies, serum insulin levels, and plasma free fatty acids were examined in a series of patients with “non-ketotic diabetic coma” and compared with the findings in ketoacidotic subjects. Serum insulin levels in six “non ketotic” patients ranged between 1 and 25 μu./ml. and were not significantly different from levels reported in patients with ketoacidosis. In addition, plasma free fatty acids were shown to be unrelated to the degree of ketonaemia. The investigation shows that neither the levels of serum insulin nor those of free fatty acids can explain the absence of hyperketonaemia in some cases.