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In the present case, a patient in whom limb apraxia and asymmetrical parkinsonism developed suggesting corticobasal degeneration, is reported. Neuropathologic examination revealed numerous tufted astrocytes in the precentral cortex in addition to the characteristic pathologic findings of PSP. Therefore, on the basis of clinicopathologic features, atypical progressive supranuclear palsy was diagnosed. In addition, the brain tissue of the present patient was investigated with an antibody specific for four‐repeat tau (4R‐tau). In the precentral cortex, numerous tau‐positive tufted astrocytes, pretangles, and threads were positive for 4R‐tau. Using a confocal microscopy we demonstrated that tufted astrocytes positive for 4R‐tau were adjacent to astrocytes positive for GFAP. The present findings suggest that accumulation of four‐repeat tau in astrocytes is a degenerative process rather than a reactive process.  相似文献   
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A rare case of pituitary metastasis of thyroid follicular adenocarcinoma occurred in a 62-year-old female manifesting as left retro-orbital pain and diplopia. Computed tomography and magnetic resonance imaging revealed a tumor in the pituitary fossa extending to the left cavernous sinus, sphenoid sinus, and prepontine cistern, destroying the upper portion of the clivus. An asymptomatic thyroid mass, probably malignant, was also found. She also had an incidental small meningioma in the posterior fossa. The pituitary tumor was partially removed, and the thyroid and posterior fossa tumors were totally removed in two operations. Both pituitary and thyroid tumors were verified to be follicular adenocarcinoma. Postoperatively, she developed panhypopituitarism for which cortisol and thyroxine replacement therapy was necessary. Three years after first therapy, she was alive but her symptoms did not improve.  相似文献   
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The cation transport and regulatory volume decrease (RVD) were investigated in the red blood cells (RBCs) of northern fur seals (Callorhinus ursinus). Extracellular Ca-dependent Na efflux was increased to threefold by hypotonicity. K–Cl cotransport activity was not detected by hypotonic medium, but measured only by nitrite or N-ethylmaleimide stimulation. RBCs were restored to their original volume after being swollen in hypoosmotic medium with Ca, though this recovery was inhibited by the addition of quinidine. Based on these results, Na/Ca exchange transporter played the major role in the regulatory volume decrease in the RBCs of northern fur seals. H. Fujise has passed away.  相似文献   
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The catecholaminergic innervation of vasopressin (VP) neurons in the paraventricular nucleus (PVN) of the rat was studied at the electron microscopic level by double-labeling immunocytochemistry combining the preembedding peroxidase-antiperoxidase method with the postembedding immunogold staining method. Tyrosine hydroxylase-like immunoreactive nerve terminals were found to establish synapses with neurophysin II-like immunoreactive neuronal perikarya and their processes. This provides morphological evidence for catecholaminergic control of the release of VP, at the PVN level.  相似文献   
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Mitotic figures of fibroblasts are seen within invasive ductal carcinoma (IDC) of the breast. This suggests that the proliferative activity of fibroblasts may play an important role in IDC tumor progression. The purpose of this study was to examine whether the proliferative activity of fibroblasts can predict lymph node metastasis (LNM) or distant-organ metastasis (DOM) of IDCs. Two hundred four consecutive patients with IDC of the breast surgically treated at the National Cancer Center Hospital East constituted the basis of this study. Proliferative activity of fibroblasts was immunohistochemically evaluated by the mouse MIB-1 monoclonal antibody against Ki-67 antigen. The MIB-1 labeling index was the percentage of fibroblasts with positively stained nuclei, and fields for cell counting were selected in inner and outer areas within IDCs. In both areas, 300 fibroblasts were counted in each high-power field. The significance of proliferative activity of fibroblasts on LNM or DOM was compared with well-known prognostic parameters. Multivariate analyses demonstrated that a MIB-1 labeling index of more than 10% of fibroblasts in the inner area of IDCs significantly increased the relative risk of LNM and hazard rate of DOM (P < 0.001 and P = 0.007, respectively). The present study indicated that the metastatic ability of IDCs is closely dependent on proliferative activity of fibroblasts in the inner area.  相似文献   
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The HIV/AIDS surveillance system in Japan, which began collecting data on the number of AIDS patients in 1984 and the number of HIV-infected persons in 1987, has played an important role in monitoring the trend and magnitude of Japan's HIV/AIDS epidemic and its distribution across various population subgroups. However, the system lacks any personal identifiers, making it impossible to eliminate duplication or to track cases for disease progression. It also does not permit the identification of the residence of HIV-infected persons because the residence of only the reporting physician is documented under the New Infectious Diseases Control Law, effective since April 1, 1999. The number of people with HIV/AIDS in Japan continues to grow. Among youth, sexually transmitted diseases, induced abortion, and sexual activities have shown a marked increase since the mid-1990s. Behavioral risk of infection for both injection drug users (IDUs) and men who have sex with men (MSM) remains alarmingly high. Accurate monitoring of infection rates is critical to the planning and evaluation of treatment, care and prevention programs. Japan should restructure its HIV/AIDS surveillance system to more accurately monitor the HIV/AIDS epidemic and related risk behaviors.  相似文献   
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