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T cell lymphoma carrying Epstein Barr virus (EBV(+) TL) is very rare among Western countries while it is much more common among Japanese. Here we report an EBV(+) TL which has been maintained for years by the use of mice with severe combined immune deficiency (SCID) mice. Lymphoma was obtained from a 55-year-old male suffering from oculomotor nerve palsy and lymphadenopathy. A small piece of biopsied tumor was transplanted into SCID mice and the lymphoma has been maintained for over 3 years with passages every 2 - 3 weeks. The maintained lymphoma, termed as TMS24, and the original lymphoma cells showed identical phenotype and genotype, including diffuse medium-sized cell morphology lacking granules, suppressor / cytotoxic immunophenotype and identical T cell receptor beta-chain gene rearrangement mode. Further, both were shown to carry an identical EBV clone in terms of the number of terminal repeats and the latency II-type restricted gene expression profile. Cytogenetically, TMS24 retained two characteristic chromosomal translocations of t(1;18)(q32;q21) and t(6;12)(p21;q24). Since only one cell line with such characters has been reported previously, TMS24 should be useful for detailed analysis of EBV(+) TL.  相似文献   
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PURPOSE: The purpose of this study was to determine whether the length of the THRA1 microsatellite, which resides in a noncoding portion of the thyroid hormone receptor-alpha1 gene, affects receptor expression and is linked to clinicopathological parameters in thyroid cancer. EXPERIMENTAL DESIGN: In 30 cases of surgically resected sporadic thyroid cancer, the length of the THRA1 microsatellite was determined by DNA sequence analysis, and expression of thyroid hormone receptor-alpha1 was assessed immunohistochemically in thin sections cut from tumor blocks. The length of THRA1 and expression of thyroid hormone receptor-alpha1 were also assessed in seven cancer cell lines. Regression analysis was used to gauge the correlation between the size of THRA1 and receptor expression. Multivariate analysis was used to test for links to the clinical parameters of gender, age, histology, stage, nodal involvement, distant metastasis, extrathyroidal invasion and tumor-node-metastasis (TNM) classification. RESULTS: A statistically significant correlation between the length of THRA1 and thyroid hormone receptor-alpha1 expression was observed in both cell lines and primary thyroid cancers. Thyroid tumors that displayed higher than average thyroid hormone receptor-alpha1 expression had expanded THRA1 microsatellites and were less aggressive as judged by TNM ranking. A statistically significant correlation was also found between low thyroid hormone receptor-alpha1 expression and more aggressive thyroid cancer, as judged by extrathyroidal invasion and nodal involvement. CONCLUSIONS: Less aggressive thyroid cancer was found to be linked to increased thyroid hormone receptor-alpha1 expression and an expanded THRA1 microsatellite.  相似文献   
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MUC1 is a highly glycosylated glycoprotein that is often overexpressed in adenocarcinomas. MUC1 has molecular diversity because of a variable number of tandem repeats (from 25-125 repeats) in the extracellular domain of its core protein. MUC1 plays an important role in facilitating invasion and metastasis of malignant cells, and it also inhibits anti-cancer immune activity against malignant cells. We hypothesize that MUC1 allele length polymorphism (variable number of tandem repeats) is associated with development of lung adenocarcinoma. We evaluated MUC1 gene polymorphism using Southern blot analysis of peripheral blood from patients with non-small cell lung cancer (n=56), patients with benign respiratory disease (n=52), and healthy volunteers (n=52). We found that large MUC1 allele length was significantly associated with lung adenocarcinoma but not with squamous cell carcinoma of the lung. Adenocarcinoma patients with a homozygous large MUC1 genotype had a worse prognosis than patients with a heterozygous (large + small) MUC1 genotype or a homozygous small MUC1 genotype. These results suggest that the large MUC1 allele is associated with susceptibility to lung adenocarcinoma and poor prognosis.  相似文献   
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Subacute combined degeneration (SCD) is a rare cause of demyelination of the dorsal and lateral columns of the spinal cord, and is a neurogenic complication due to vitamin B12 deficiency. This report concerns a patient with progressive sensory disturbance, but no abnormal neurological findings. A 73-year-old man with gastrectomy presented with a 6-month history of gradually worsening tingling in both hands. Magnetic resonance imaging (MRI) of the cervical spine clearly showed symmetrical high-signal areas on T2WI involving the posterior columns of the cervical cord from C2 through C6. A diagnosis of SCD of the spinal cord was considered and confirmed by laboratory findings. The patient was treated with vitamin B12 supplements and showed gradual improvement in his clinical symptoms. Repeat MRI of the cervical spine after 3 months indicated a slight decrease in the area of the abnormal signal. Among all the possible causes of myelopathy, SCD of the spinal cord, involving neurological complications due to vitamin B12 deficiency, is one of the less often encountered diseases. Nevertheless, SCD should be considered in the differential diagnosis of all spinal cord, peripheral nerve, and neuropsychiatric disorders.  相似文献   
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We devised a special instrument to assess intraoperative pelvic motion and used this device to measure intraoperative pelvic motion in three dimensions. A total of 100 total hip arthroplasties (THAs) were performed using this device. Two approaches were utilized: 52 THAs were performed with the posterolateral approach and the remaining 48 with the translateral approach. The average angle of pelvic tilt in the THAs with the translateral approach was less than that with the posterolateral approach. The average internal rotation angle was 1.75° with the translateral approach and 14.25° with the posterolateral approach. With the posterolateral approach, the internal rotation of the pelvis frequently occurred during retraction of the femur using a Hohmanns retractor placed at the anterior rim of the acetablum, with flexion and internal rotation of the affected hip.  相似文献   
79.
We report a 51-year-old Japanese man with chronic alcoholism who complained of mental confusion following respiratory and intestinal infections. The splenium of the corpus callosum showed hyperintensity on both diffusion-weighted MR images and fluid-attenuated inversion recovery images and hypointensity on T1-weighted images. These findings were resolved on MR images obtained 3 days later. He showed complete neurological recovery within 2 months. We suspected that he had mild encephalopathy with a reversible splenial lesion after systemic viral or bacterial infection.  相似文献   
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