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91.
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders.  相似文献   
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Many Tau-positive glia with paired nuclei and astrocyte type morphology were identified in three brains from patients with progressive supranuclear palsy (PSP). They were positive by Bielschowsky's and Bodian's silver staining as well as by immunostaining with Tau-2, Alz-50, anti-GFAP and anti-paired helical filament antibodies, but not with anti-ubiquitin antibody. They were predominantly localized in the striatum, thalamus and frontal cortex but were not seen in white matter and were not plentiful in areas of heavy neuronal degeneration. Electron microscopy clearly showed the nuclear pairing and localized the Tau protein to bundles suggestive of microtubules in the cytoplasm and proximal processes. Such glial cells were rarely seen in cases of other neurodegenerative diseases or neurologically normal controls. These data suggest that there is an unusual gliotic reaction in PSP in brain areas which show relatively little neuronal loss.  相似文献   
96.
The clinical significance of eosinophils in urine was examined. Eosinophils were found in 9 out of 10 cases of interstitial cystitis, and there were more than 50 eosinophils in 50 fields in 6 of these cases. Although the number of eosinophils almost correlated with the number of leucocytes, the relationship between eosinophils and leucocytes in interstitial cystitis was different in acute and chronic cystitis. Since urinary eosinophils could be observed in cases of interstitial cystitis in which leucocytes were as low as 3 to 10 per field and the number of eosinophils was not decreased by chemotherapy, the urinary eosinophils in interstitial cystitis may be of allergic significance and reflect eosinophilic infiltration into the bladder wall.  相似文献   
97.
We report 3 cases of müllerian duct cyst. Percutaneous puncture, aspiration and instillation of a sclerosing agent under ultrasound guidance was performed in each case. Ultrasound is valuable in the diagnosis is of cysts in the region of the prostate and seminal vesicles. Aspiration under ultrasound guidance would also be of therapeutic value.  相似文献   
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Primary aqueductal stenosis is one of the main causes of congenital hydrocephalus in humans and experimental models. The congenitally hydrocephalic rat strain LEW/Jms is one such model. In this report, we describe further detailed histological features of periaqueductal structure, including the posterior commissure, subcommissural organ (SCO), and ependyma, and discuss the changes in these structures in relation to the cause of hydrocephalus. Coronal sections of the aqueduct in normal rats showed that the usual ependyma was absent in the center of the base facing the dorsal side, which was replaced by tall columnar cells. On the other hand, in hydrocephalic rats the ependyma encircled the aqueductal cavity. In midline sagittal sections, normal and hydrocephalic rats showed the SCO, although the SCO in hydrocephalic rats was shorter than in normal rats. There was also a marked difference between normal and hydrocephalic rats in the dorsoventral dimension of the rostral midbrain. In hydrocephalus, this dimension was large in comparison with normal rats. The superior collicular commissure located caudal to the posterior commissure ran along the ventral side of the midbrain in rats with hydrocephalus, and there was a cell-depleted area just dorsal to the superior collicular commissure. The same findings were observed from the 17th day of gestation until the postnatal period. Although the role of the SCO has been widely discussed from the viewpoint of secretory function, the present study indicated that this organ might be involved in the formation of the shape of the aqueduct.  相似文献   
100.
The identification and diagnosis of thyroid metastases from renal cell carcinoma are rare in living patients in spite of more frequent incidence during autopsy. We reported two cases of thyroid metastases from renal cell carcinoma. In both cases, histological examination revealed metastasis from renal cell carcinoma and negative immunohistological stain for thyroglobulin ruled out primary thyroid carcinoma.  相似文献   
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