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This study was performed to determine whether power Doppler sonography is superior to color Doppler sonography in the depiction of the normal fetal intrarenal vasculature during pregnancy. Twenty-five fetal kidneys in 22 healthy fetuses between 22 and 40 weeks of gestation (mean 32.6 weeks) were studied with color and power Doppler sonography with a 3.75 MHz transducer. The efficacy of power and color Doppler sonography were compared in assessing fetal renal vasculature. Power Doppler sonography demonstrated diffuse "blush" in almost the entire cortex in 21 of 25 fetal kidneys, whereas it was demonstrated in half of the cortex in the other four kidneys. Color Doppler sonography failed to demonstrate a cortical blush in fetal kidneys. Power Doppler sonography has been shown to be superior to color Doppler sonography in the depiction of normal fetal intrarenal vasculature during pregnancy by demonstrating vascular blood flow better than color Doppler sonography.  相似文献   
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Our objective was to compare the relationship between age, basal follicle stimulating hormone (FSH) level and ultrasound-measured mean ovarian volume (MOV) and mean antral follicle counts (MFC) in a group of infertile and fertile women between the ages of 35 and 45 years. Menstrual cycle day 3 serum FSH, MOV and MFC were analyzed in 62 infertile and 53 fertile women. Basal FSH and MFC did not differ between infertile and fertile women, whereas MOV was significantly smaller in infertile women (p < 0.05). In the infertile group, there was a negative correlation between MOV and age (rho = -0.389, p < 0.05), between MOV and basal FSH (rho = 0.495, p < 0.01), and between MFC and age (rho = -0.553, p < 0.01). In the fertile group, there was a strong negative correlation between MOV and basal FSH (rho = -0.631, p < 0.01), and between MFC and basal FSH (rho = -0.710, p < 0.01). Mean basal FSH, MOV and MFC did not differ between subgroups of patients with different causes of infertility. In the infertile group, patients with small ovaries of volume less than 1.8 cm(3) (mean volume -1 SD) had higher mean basal FSH (p < 0.05) and lower MFC (p < 0.01) levels than patients with normal ovarian volume. In conclusion, transvaginal ultrasound (TVU) indices and indirect hormonal parameters of ovarian reserve were similar in infertile and fertile women aged between 35 and 45 years. It is suggested that, in infertile women above 35 years of age, TVU rather than hormonal parameters be preferred, based on our data showing a stronger association between age and TVU indices of ovarian reserve than between age and increase in basal FSH level. Thus, TVU assessment of ovarian volume and antral follicle counts is a practical and cost-effective, if not better, technique for ovarian reserve testing.  相似文献   
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The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.  相似文献   
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Intraosseous lipomas are among the most uncommon bone tumors. They arise most often in the appendicular skeleton. There are very few reported cases of intraosseous lipomas within the skull bones. We report a case of intraosseous lipoma of the frontal bone with conventional radiography and CT findings.  相似文献   
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The authors present two cases of necrotizing fasciitis (NF), one case of dermatomyositis and one case of posttraumatic muscle injury, which have similar magnetic resonance imaging findings in terms of skin, subcutaneous fat, superficial and deep fasciae and muscle involvement. These cases highlight the need for cautious interpretation of magnetic resonance imaging (MRI) findings, for they are nonspecific and the preoperative decision should be based mostly on the evolution of the clinical status.  相似文献   
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