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Automated biopsy devices: a blinded evaluation 总被引:4,自引:1,他引:3
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Ferritin was purified 33,000-fold from the plasma of patients with idiopathic hemochromatosis. The plasma ferritin was labeled with 131I and injected into 2 normal men. Clearance was found to be relatively slow, with 50% 131I-ferritin remaining in the plasma at 27-30 hr. The fraction of plasma ferritin that bound to concanavalin-A was found to be cleared more slowly than the nonbinding fraction. These findings confirm our previous suggestion that glycosylation is a major factor prolonging the survival of ferritin in the plasma, but differ from the results of earlier studies in experimental animals and preterm infants, which indicated very rapid plasma ferritin turnover. 相似文献
997.
Watt AC; Ackerman LV; Windham JP; Shetty PC; Burke MW; Flynn MJ; Grodinsky C; Fine G; Wilderman SJ 《Radiology》1986,159(1):39-42
To evaluate its potential for differentiating benign from malignant breast lesions, digital subtraction angiography of the breast (DSAB) was performed in 23 women with mammographic evidence of disease, and the results were compared with surgical biopsy findings. The DSAB technique employed breast immobilization with modest compression and bolus injection; following the injection of contrast material, 30-40 sequential subtraction images were obtained over a 5-minute interval. The average technical settings were 50 k Vp and 10 mAs, resulting in an estimated radiation dose to the breast of 0.05 mrad (0.5 mu Gy) per exposure. DSAB consistently demonstrated retention of contrast material and abnormal vasculature in malignant lesions but not in benign lesions. In the 22 breast lesions for which there was histopathologic correlation, DSAB correctly categorized eight of nine malignant and 11 of 13 benign lesions. Although this series is small, the initial results of DSAB suggest its potential for differentiating benign from malignant lesions. 相似文献
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999.
Adrenoleukodystrophy: correlating MR imaging with CT 总被引:6,自引:0,他引:6
Kumar AJ; Rosenbaum AE; Naidu S; Wener L; Citrin CM; Lindenberg R; Kim WS; Zinreich SJ; Molliver ME; Mayberg HS 《Radiology》1987,165(2):497-504
The effect on the brain of the sex-linked recessive form of adrenoleukodystrophy was studied in 40 boys, 4-18 years old. All underwent computed tomography (CT) scanning; six underwent magnetic resonance (MR) imaging. MR showed a high sensitivity in demonstrating white matter disease. Auditory pathway disease was characterized as involvement of the lateral lemniscus and medial geniculate body, and visual pathway disease was characterized by lateral geniculate body, Meyer loop, and optic radiation involvement. Contrast-enhanced CT still proved to have a greater capacity (at this time) to show the active, advancing form of the disease and concomitant calcifications. This large CT series also demonstrated the broad and variable expressions of adrenoleukodystrophy, which allowed the unification of previously described atypical forms of the disease. 相似文献
1000.
Ten percent of children with biliary atresia have an associated complex of anomalies, including polysplenia, azygous continuation of the inferior vena cava, preduodenal portal vein, hepatic arterial anomalies, and bilaterally bilobed lungs. These abnormalities will not be detected if the preoperative workup is limited to hepatobiliary nuclear scanning. Ultrasonography is important in the preoperative evaluation of patients suspected of having biliary atresia. It is important to identify the associated abnormalities preoperatively because they have an impact on the initial portoenterostomy and may preclude subsequent orthotopic liver transplantation. 相似文献