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991.
R Lehtinen H Siev?nen J Viik V Turjanmaa K Niemel? J Malmivuo 《Canadian Metallurgical Quarterly》1996,78(9):1002-1006
In this comparative cross-sectional study, we evaluated whether a novel computerized diagnostic variable, ST-segment depression/heart rate ST/HR analysis during both the exercise and postexercise recovery phases of the exercise electrocardiography (ECG) test, can detect coronary artery disease more accurately than methods using either exercise or recovery phase alone. The study population comprised 347 clinical patients referred for a routine bicycle exercise ECG test at Tampere University Hospital, Finland. Of these, 127 had angiographically proven coronary artery disease, whereas 13 had no coronary artery disease according to angiography, 18 had no perfusion defect according to technetium-99m sestamibi single-photon emission computed tomography, and 189 were clinically normal with respect to cardiac diseases. For each patient, the maximum values of the ST/HR hysteresis, ST/HR index, end-exercise ST depression, and recovery ST depression were determined from the Mason-Likar modification of the standard 12-lead exercise electrocardiogram [aVL, aVR, and V1 excluded]. The diagnostic performance of these continuous diagnostic variables was compared by means of receiver-operating characteristic analysis. The area under the receiver-operating characteristic curve of the ST/HR hysteresis was 89%, which was significantly larger than that of the end-exercise ST depression (76%, p < or = 0.0001), recovery ST depression (84%, p = 0.0063), or ST/HR index (83%, p = 0.0023), indicating superior diagnostic performance of the ST/HR hysteresis independent of the partition value selection. In conclusion, computerized analysis of the HR-adjusted ST depression pattern during the exercise phase, integrated with the HR-adjusted ST depression pattern during the recovery phase after exercise, can significantly improve the diagnostic performance and clinical utility of the exercise ECG test for the detection of coronary artery disease. 相似文献
992.
Translated from Steklo i Keramica, No. 3, pp. 2–5, March, 1993. 相似文献
993.
Of 1,666 patients who underwent fine needle aspiration for breast lumps, 4 developed pneumothorax as a complication. The incidence of this complication in our patients is 1:417. The clinical manifestations were immediate chest pain, shoulder pain and, occasionally, dyspnea that developed later. Observation is sufficient treatment in most patients, and rarely is drainage of the pneumothorax required. 相似文献
994.
The contour path finite-difference time-domain (FDTD) method is used for modeling pyramidal horn antennas with or without composite E-plane inner walls. To model the pyramidal horn surface, a locally distorted grid is used. Modified equations are obtained based on the locally distorted grid and the assumptions of the contour path method. The developed algorithm is validated by comparing computed antenna gain patterns, with and without the presence of composite material, with available measurements 相似文献
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999.
R. P. Voitovich Yu. V. Naidich G. A. Kolesnichenko 《Powder Metallurgy and Metal Ceramics》1992,31(6):494-497
Translated from Poroshkovaya Metallurgiya, No. 6(354), pp. 40–44, June, 1992. 相似文献
1000.
S. I. Glinchak Yu. A. Egorov R. R. Aliev E. D. Radchenko B. K. Nefedov N. A. Grigor'ev 《Chemistry and Technology of Fuels and Oils》1992,28(3):175-177
Translated from Khimiya i Tekhonologiy Topliv i Masel, No. 3, pp. 33–34, March, 1992. 相似文献