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The aims of this study were to assess the role of (99m)Tc-tetrofosmin scintigraphy in the diagnosis of malignant vs. benign musculoskeletal tumours and to determine the relationship between P-glycoprotein expression and tetrofosmin uptake in malignant lesions. Forty-six patients (32 malignant, 14 benign) with various musculoskeletal lesions were studied. Each patient underwent (99m)Tc-methylene diphosphonate three-phase bone scanning initially. At least 2 days later, dynamic and static (99m)Tc-tetrofosmin scans were obtained. The tetrofosmin scans were evaluated by visual and quantitative analysis. The count ratio of the lesion to the contralateral normal area (uptake ratio, UR) was calculated from the region of interest drawn on the tetrofosmin scan. The lesions were then resected by open biopsy to obtain a histopathological diagnosis. P-glycoprotein levels were determined immunohistochemically in 22 of 32 malignant lesions. A significant difference between the mean UR values of benign and malignant lesions was found (1.36 +/- 0.47 vs. 3.35 +/- 2.08, P = 0.000). Visual analysis showed an accuracy of 85%, and the accuracy of the quantitative analysis was 87% with the threshold level of UR as 1.76. When perfusion findings were added to the evaluation criteria, the accuracies of visual and quantitative analysis were increased to 87% and 89%, respectively. The relationship between the levels of P-glycoprotein and the UR values of tetrofosmin was not statistically significant (r = -0.235, P = 0.2). In addition, the mean UR value of the patients with P-glycoprotein expression was not statistically different from that of the patients without P-glycoprotein expression (3.01 +/- 1.48 vs. 4.27 +/- 2.90, P = 0.297). In conclusion, visually significant tetrofosmin uptake and increased perfusion in a musculoskeletal lesion strongly suggest that the lesion is malignant (positive predictive value, 96%). P-glycoprotein expression was not found to be a major factor interfering with 30 min tetrofosmin uptake in a malignant musculoskeletal lesion. However, the relatively high false-negative rate among negative results (28%) limits the value of (99m)Tc-tetrofosmin scintigraphy as a single diagnostic tool in differentiating between benign and malignant musculoskeletal tumours.  相似文献   
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Polycystic horseshoe kidney.   总被引:1,自引:0,他引:1  
Horseshoe kidney is a renal fusion anomaly during embryogenesis. The reported incidence of horseshoe kidney varies from 1 in 400 to 1 in 1,800 live births (commonly quoted 1 per 400) [Wilson and Azmy 1986]. Adult polycystic kidney disease is a hereditary disorder with autosomal-dominant transmission. Its incidence is approximately one in every 1,000-5,000 cases [Levine et al. 1997]. Polycystic horseshoe kidney is a very rare occurrence with incidence ranges of 1 in 134,000 to 1 in 8,000,000 cases [Brum et al. 1997]. We add another case to the literature.  相似文献   
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We have not encountered any brain single-photon emission tomography (SPET) study performed in adolescent depressed patients in the literature. Therefore, we used technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) brain SPET in adolescent patients with major depressive disorder (MDD) to examine the possible changes in cerebral perfusion and the possible association between perfusion indices and clinical variables. Fourteen adolescent out-patients (nine females, five males; mean±SD age: 13.11±1.43 years; range: 11–15 years) fulfilling the DSM-IV criteria for MDD and 11 age-matched healthy control subjects (six females, five males; mean±SD age: 13.80±1.60 years; range: 12–15 years) were included in the study. 99Tc-HMPAO brain SPET was performed twice in the patient group and once in the control group. The first SPET investigation was performed under non-medicated conditions and the second was performed after depressive symptoms had subsided. A relative perfusion index (PI) was calculated as the ratio of regional cortical activity to the whole brain activity. We found significant differences between the PI values of the untreated depressed patients and those of the controls, indicating relatively reduced perfusion in the left anterofrontal and left temporal cortical areas. No significant differences in regional PI values were found between the remitted depressed patients and the controls. Our study suggests that adolescent patients with MDD may have regional cerebral blood flow deficits in frontal regions and a greater anterofrontal right-left perfusion asymmetry compared with normal subjects. The fact that these abnormalities in perfusion indices have a trend toward normal values with symptomatic improvement suggests that they may be state-dependent markers for adolescent MDD. Received 11 January and in revised form 11 February 1998  相似文献   
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A case is reported here of symptomatic intraurethral anterior midline prostatic cyst in a 52-year-old man whom transurethral resection of the cyst was performed successfully establishing the resolution of voiding symptoms.  相似文献   
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This study aimed to objectively evaluate autonomic nervous function in children with primary Raynaud’s phenomenon (PRP). Thirty-two children with PRP and 30 healthy subjects were included in the study. We analyzed heart rate variability (HRV) in the time domain by the following six standard time-domain measures: standard deviation of all normal R-R intervals during 24 h (SDNN), standard deviation of all normal R-R intervals for all 5-min segments (SDNNi), standard deviation of the average normal R-R intervals for all 5-min segments (SDANN), root mean square of the successive normal R-R interval difference, percentage of successive normal R-R intervals longer than 50 ms, and triangular index (integral of the density distribution of NN intervals divided by the maximum of the density distribution). The mean heart rate throughout 24 h was significantly higher in the PRP group than in the control group (p?=?0.001). Although heart rate during the activity period was not significantly different from that during the night period, it was higher in the PRP group than in the control group (p?=?0.002). In children with PRP, HRV analysis showed significantly lower values of SDNN (p?=?0.01), SDNNi (p?=?0.005), SDANN (p?=?0.02), and HRV triangular index (p?=?0.02) compared with the control group. HRV analysis for sympathovagal balance demonstrated a preponderance for the sympathetic component in patients with PRP. We conclude that all time-domain parameters evaluated in HRV analysis are significantly lower in children with PRP than in healthy subjects.  相似文献   
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