Meditsinskaia tekhnika
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Meditsinskaia tekhnika · Jan 1978
[Possible use of new corrosion-resistant steels in the manufacture of medical instruments].
Demands on metals intended for the manufacture of medical instruments call for the use of corrosion-resisting grades of steel with high strength characteristics. Grades of steel of the martensite class reinforced by age hardening (martensive-aging) and mild grades of steel (chrome-manganese and chrome-nickel) have a number of valuable advantages over the steel of other classes. The possibility of obtaining high strength with low carbon dontent ensures great plasticity, toughness and brittle failure resistance along with corrosion-resistance and the possibility of achieving a substantial simplification in technology of making the instruments. Investigations of martensite-aging grades of steel--ep832,ochX11H9M2d2Tyu, O3X11HMd2yu and O3X13g3Md2 demostrated them to hold good promise for the manufacture of surgical and atraumatic needles, and rod-type stomatological instruments.
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The purpose of the work was to design an appliance for reliable detection of ventricular fibrillation. Frequency-amplitude spectrum of electrocardiograms taken in dogs with normal rhythm and fibrillation, as well as the impulse ratio in normalcy, tachycardia and in fibrillation were investigated. An appliance for automatic separation of ventricular fibrillation by referring to pulse ratio is described. The designed device is shown to have a high degree of discrimination and noise-immunity.