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To assess the sensitivity of standard echocardiography in detecting ventricular motion abnormalities in patients with coronary artery disease (CAD) without prior myocardial infarction, 56 consecutive patients with a history of angina pectoris were studied during an angina-free period. In the 48 patients with adequate echocardiograms, the amplitude of septal and posterior wall motion in the high, mid, and low left ventricle was determined and used to predict prospectively in a blinded fashion the sites of angiographically-determined CAD. Twenty-eight of 35 patients (80%) with disease of the left anterior descending artery (LAD) had diminished interventricular septal motion (P less than 0.001) and 14 of 27 patients (52%) with disease of posterior vessels had diminished posterior wall motion on echocardiogram. When abnormalties of echocardiographic wall motion were compared with left ventriculography, the results were similar. Echocardiography may aid in predicting the presence and distribution of CAD, especially LAD disease. 相似文献
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RH Ward GA Whyley DV Fairweather EI Allen T Chard 《Canadian Metallurgical Quarterly》1977,84(5):363-369
Serial estimations were made in plasma of 17beta-oestradiol (E2), progesterone and human placental lactogen (HPL) in 43 patients and of human chorionic gonadotrophin (HCG) in 34 patients during mid-trimester abortions induced with intra-amniotic prostaglandin F2alpha (PGF2alpha. Mean plasma concentrations of all the hormones showed a progressive fall after PGF2alpha. There was no relationship between the fall in levels of progesterone, HPL and HCG and the induction-abortion interval, signs of fetal distress or of intrauterine fetal death. Both the control level and the rate of fall of E2 were related to the induction-abortion interval and a rapid decline preceded intrauterine fetal death. The relationships of the progesterone/E2 ratio and the amniotic fluid volume/progesterone ratio to the induction-abortion interval were examined. The variation in the time at which significant falls in the concentration of individual hormones occurred was probably related to their respective half-lives in plasma. 相似文献
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Changes in sugars and polyols content of fruits and leaves of three cultivar of peach, from fruit set to over maturity, have been studied. Sucrose, glucose, fructose and sorbitol were found both in leaves and in fruits. In fruits, inositol and galactose were also found but only in traces. Redhaven fruits show the greatest total sugars content (sorbitol included) (866 mg/g.d.m.)followed in order by Favorita and Prodigiosa ones (771 and 694 mg/g.d.m.) For Redhaven and Favorita fruits, at harvest matuity, the sugar present in greatest amount was sucrose followed in order by glucose, fructose and sorbitol. On the contrary, in Prodigiosa fruits the order was sucrose, sorbitol, fructose and glucose. In the leaves of three cultivar, the compound present in the greatest amount was sorbitol followed by sucrose, glucose and fructose. The sucrose decrease in leaves during fruit growth could confirm that the disaccharide is the main sugar transported from the leaves to the fruits. 相似文献
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The purpose of this study was to assess the possibility of measuring directional microphone hearing aids (DMHAs) using standard hearing aid test instruments in a sound field environment. The use of DMHAs is increasing and research has shown that under certain difficult listening situations, superior results are obtained by hearing impaired individuals with directional versus omnidirectional microphone arrangements. However, valid electroacoustic evaluation of the DMHAs cannot be accomplished using the conventional hearing aid test box. The ideal environment for such evaluations is an anechoic chamber, a facility not found in most audiological clinics. Results show that if the proper precautions are observed, the electroacoustic characteristics of DMHAs can be measured in a sound field environment using conventional hearing aid test instrumentation. Validation of this procedure was carried out by comparing sound field results with those obtained in an anechoic chamber. 相似文献