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The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
64.
Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
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65.
This article presents the relationship between wage labor, housewifery, and health from a gender perspective. The relationship between the two types of work determines the characteristics and meaning of daily life. The methodology combined quantitative and qualitative techniques. An individual questionnaire was applied to 256 male and 121 female workers (n = 377) in a modern pharmaceutical factory in Mexico. In addition, seven in-depth interviews were performed with selected employees. Despite important similarities between female and male wage-earners, there were two key differences: gender segregation in the workplace and the division of household work. The social determinants of this uneven situation result from a complex gender relationship, leading to different disease profiles and health concepts.  相似文献   
66.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis.  相似文献   
67.
Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations.  相似文献   
68.
The determinations of the amino acid pools, including tryptophan (by fluorescence spectrometry), in the arterial and venous blood of the mother, the arterial and venous blood of the fetus (cord blood), the amniotic fluid and the placenta was done in eight women at the moment of delivery. Only nine amino acids (asp, try, met, phe, ser, cys, lys, gly, thr) were significantly retained and four (arg, glu, pro and glu-NH2) were significantly released by the fetal tissues. In contrast with this behavior most amino acids were retained by the maternal tissue, try, phe and hist showing the highest retention. When the amino acids are grouped as essential and nonessentials, the maternal tissues retained both categories without apparent discrimination, while the fetal tissues retained essential amino acids preferentially. Our results emphasize the importance of the placenta as the regulating system of the fetal milieu under normal conditions. Thus human fetal blood levels of amino acids are patterned after the placental ones and not after the maternal values obtained at the same time. It is apparent that the placenta seems to function as a nonspecific retention filter for outgoing amino acids, but that its function is selective in respect to the release of amino acids into the fetal circulation.  相似文献   
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Computed tomography in the diagnosis of herniated nucleus pulposus   总被引:2,自引:0,他引:2  
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