A hypodermic pressure manometer utilizing the bonded wire resistance strain gauge.
The recent development of the bonded resistance wire strain gauge has led to its use as a device for measuring physiological pressure phenomena. Further application of the strain gauge has been as an instrument for measuring intravascular blood pressures and other pressure phenomena in biology and medicine.
Bone marrow pressure in leukemic and non-leukemic patients.
It has been a frequent observation that many patients with leukemia and multiple myeloma bleed freely through the marrow needle at the time of bone marrow aspiration although hemorrhagic tendencies may not be present clinically. In addition, throbbing bone pain and bone tenderness are not infrequently observed in these patients (1). Such clinical observations suggest that some degree of pressure elevation may be present in the marrow cavity in these diseases. It was believed of interest to determine the pressure relationships within the human marrow cavity under a variety of physiologic stimuli.
A new power measuring circuit using a bridge-connected magnetic circuit and another magnetic core
The authors describe the operating characteristics of an oscillating circuit using a bridge-connected magnetic circuit and another magnetic core. A square-shape output voltage is obtained in the oscillating circuit. The pulsewidth in positive and negative half cycles of output voltage changes with the current of the U-form core windings and with the signal voltage applied to the exciting windings. The mean value of the output voltage varies in proportion to the product of the current and the signal voltage. Utilizing this feature, an application of the oscillating circuit to a novel power measuring circuit of simple construction is presented. >