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31.
PurposeTo compare contrast-enhanced T1-weighted (CE-T1WI) magnetic resonance imaging (MRI) with computed tomography (CT) for postimplant dosimetry and seed recognition in prostate brachytherapy.Methods and MaterialsA total of 245 patients who received 125I prostate brachytherapy with or without external beam radiotherapy were enrolled. For postimplant analysis, CT and MRI scans were obtained at 1 month after seed implantation. For MRI-based dosimetry, T2-weighted images were fused with the CE-T1WI; the prostate was delineated on the T2-weighted images, and the seed detection was performed manually on the CE-T1WI. In CT-based dosimetry, the seed detection was essentially performed automatically. The dosimetric results obtained by MRI-based and CT-based dosimetry were compared.ResultsThe mean prostate D90 (the minimum dose received by 90% of the prostate volume) estimated by MRI-based and CT-based dosimetry were 113% and 115%, respectively, with no significant difference. The mean prostate V100 (the percent volume of the postimplant prostate receiving 100% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 95.2% and 95.8%, respectively, again with no significant difference. The mean prostate V150 (the percent volume of the postimplant prostate receiving 150% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 52.8% and 57.0%, respectively (p < 0.01). In all of the 35 patients (14%) in whom the MRI-based V150 were at least 10% lower than the CT-based results, the seed detection by CT-based dosimetry was overestimated in highly seed-clustered areas or in the areas close to calcifications because of reconstruction artifacts in CT images.ConclusionsMRI-based dosimetry using CE-T1WI appears to be acceptable. Our results suggest that MRI-based dosimetry is a practical method for estimation of the higher dose distribution, especially if seeds are clustered together or when they are close to calcifications.  相似文献   
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Accumulating evidence has shown that diabetic patients are increasing in number, and renal and cardiovascular complications are the most common cause of death in diabetic patients. Thus, it would be of considerable value to identify the mechanisms involved in the progression of renal impairment and cardiovascular injury associated with diabetes. Recent evidence also indicated that multifactorial intervention is able to reduce the risk of cardiovascular disease and death among patients with diabetes and microalbuninuria. In this pilot study, we examined the effects of intensified multifactorial intervention, with tight glucose regulation and the use of valsartan and fluvastatin on ambulatory blood pressure (BP) profile, estimated glomerular filtration rate (eGFR), and urinary albumin to creatinine ratio (UACR), in 20 hypertensive patients (16 male and 4 female) with type 2 diabetes mellitus and overt nephropathy. After 12 months of intensified treatment, office BP, fasting plasma glucose (FPG), and low-density lipoprotein cholesterol (LDLC) were significantly decreased compared to baseline (systolic blood pressure (SBP), 130 ± 2 vs. 150 ± 1 mmHg; diastolic blood pressure (DBP), 76 ± 1 vs. 86 ± 1 mmHg; FPG, 117 ± 5 vs. 153 ± 7 mg/dl; LDLC, 116 ± 8 vs. 162 ± 5 mg/dl, P < 0.0001). Also, compared to the baseline values, the daytime and nighttime ambulatory BP and short-term BP variability were significantly decreased after 12 months. Furthermore, while eGFR was not altered (44.3 ± 5.1 vs. 44.3 ± 6.5 ml/min/1.73 m(2), not significant (NS)), UACR showed a significant reduction after 12 months of intensified treatment (1228 ± 355 vs. 2340 ± 381 mg/g-cr, P < 0.05). These results suggest that the intensified multifactorial intervention is able to improve ambulatory BP profile, preserve renal function, and reduce urinary albumin excretion in type 2 diabetic hypertensive patients with overt nephropathy.  相似文献   
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BACKGROUND AND METHODS: Sonographic (US) findings of Chilaiditi syndrome have been rarely reported in the literature. We reviewed 18 cases of Chilaiditi syndrome to pinpoint its US pattern. RESULTS: (1) US showed gas echoes of different sizes superimposed over the entire liver in two cases and over the right hepatic lobe in six cases, leading to a high suspicion of Chilaiditi syndrome. (2) US showed a small gas echo in the hepatodiaphragmatic space, mimicking pneumoperitoneum in eight cases. In this instance, altering the patient's position allowed for confirmation of the lack of a change in the location of the gas echo, unlike cases of pneumoperitoneum. (3) The hepatic surface appeared as a hyperechoic mass in two cases. CONCLUSION: Knowledge of US patterns of Chilaiditi syndrome helps avoid confusion with pneumoperitoneum or hepatic masses.  相似文献   
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The antitumor activity of lipopolysaccharide (LPS) was investigated in BCG-treated mice. C3H/He mice and CDF1 mice were injected with BCG and then were inoculated with syngeneic mouse hepatoma MH134 and mastocytoma P815 respectively. Hemorrhagic necrosis and retarded growth of tumor were observed after an intravenous (i.v.) injection of LPS, when tumor cells had been inoculated subcutaneously (s.c.). However an intraperitoneal (i.p.) injection of BCG plus LPS did not increase the mean survival time of mice that had been inoculated with tumor cells i.p. Sera from mice that had been treated with BCG plus LPS i.v. were cytotoxic for cultured tumor cells. These results seemed to indicate that growth-inhibitory effects of LPS on tumors inoculated s.c. were mediated by a humoral factor.  相似文献   
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Mesenteric panniculitis: sonographic findings   总被引:3,自引:0,他引:3  
BACKGROUND: Mesenteric panniculitis (MP) is a relatively rare disease, and sonographic (US) and color Doppler findings have been infrequently reported. METHODS: We reviewed the clinical data and US and Doppler results of three cases of MP to determine the role and limitations of these techniques. RESULTS: The sole presenting clinical sign was a soft mass. On US the lesion was imaged as a poorly margined echogenic mass with hypoechoic areas. Color Doppler US visualized the nondeviated mesenteric vessels within the mass, which enabled us to perform a safe guided biopsy. CONCLUSIONS: US is useful as an initial diagnostic tool, but its results must be interpreted carefully. Color Doppler US is very useful in demonstrating fine vessels and helps in performing a safe needle biopsy.  相似文献   
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A patient with steroid hormones or androgen producing bronchogenic adenocarcinoma was presented. Clinically he had a mediastinal mass and bilateral multiple pulmonary nodules which showed a rapid growth despite cancer chemotherapy. At postmortem examination, radioimmunoassay of the tumor tissue revealed androgen and their precursors. The mitochondria of the tumor cells resembled those of cells in the zona reticularis of the adrenal cortex.  相似文献   
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