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191.
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Nephroblastoma (Wilms' tumor) is the most common renal malignancy in childhood. Extrarenal Wilms' tumor is uncommon, and the diagnosis is almost always postsurgical. The authors report two cases, located in the sigmoid mesocolon, one of these having an associated horseshoe kidney. Both were treated with excision followed by chemotherapy. They are now 36 months and 7 months postchemotherapy, respectively, and are symptom and recurrence free. Both had favorable histological findings. Association with a horseshoe kidney raises an important issue regarding the histogenesis of these tumors. The authors believe that there is a nexus between the fusion of metanephric blastema during the sixth to seventh week of intrauterine life and the "ectopic" metanephric blastema cells that may give rise to extrarenal Wilms' tumor. Association with a horseshoe kidney with an extrarenal Wilms' tumor has been reported on five previous occasions. The authors closely examine the link between the two.  相似文献   
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Atypical ("pseudosarcomatous"), cutaneous, fibrous histiocytoma is a rare connective tissue tumor arising on the trunk and limbs in young adults. Its histological diagnosis is difficult. We report the case of a 25-year-old woman who presented a nodule on her left leg. Two years after an incomplete excision, she developed a large local recurrence. Additional radiotherapy, after total reexcision was performed. This treatment was successful and no further recurrence occurred. Clinicopathological features of atypical ("pseudosarcomatous"), cutaneous, fibrous histiocytoma are reviewed. Differential diagnoses, including atypical fibroxanthoma, angiomatoid fibrous malignant histiocytoma and aneurysmal fibrous histiocytoma are discussed.  相似文献   
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The incidence of postoperative hypothyrosis after subtotal resection of the thyroid for diffuse toxic goiter is rather high, 40-50% according to many authors. A method is suggested permitting assessment of the share of "active zones" during surgery. A certain amount of thyroid tissue is left with due consideration for this share, this amount being sufficient to attain an euthyroid state in the postoperative period.  相似文献   
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The CO2 laser can be used for the treatment of various lesions of the eyelids and peri-orbital region with the advantage over other modalities of precise, controllable, hemostatic, non contact atraumatic ablation with the reduction of post-operative pain and improved cosmetic results. Its application in palpabral and peri-orbital surgery is recommended.  相似文献   
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Circuit complexities reduce overall reliability and mean-time-between-failure rates of today's very large processing arrays. Our integrated, three-level hierarchy of reconfiguration methods provides reasonable levels of fault tolerance for such systems. Operating in a completely distributed fashion, the hierarchy does not require that any components be fault free. It significantly improves array reliability by using a combination of transient fault rollback techniques and local and global reconfiguration algorithms  相似文献   
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To determine whether defective interfering (DI) particles alter viral encephalitis BALB/c mice were inoculated intranasally with standard vesicular stomatitis virus (VSV) and its DI particles. Addition of 10(7) PFU equivalents of DI particles to 10(5) PFU of VSV reduced morbidity but did not delay disease onset. Less mortality was also observed. When 10(3) PFU equivalents of DI particles or UV-irradiated DI particles were substituted, these effects were absent. Attempts to correlate mortality with virus recovered from the brain could not be made due to considerable variations in the few surviving mice. Immunohistochemical analysis obtained from 121 mice showed that inoculation of DI particles limited the specific pathways of VSV antigen dissemination within the central nervous system, and new pathways were not substituted. In the group of mice with reduced mortality due to DI particles, at day 4 post inoculation VSV antigen was limited to the outer layers of the glomeruli of the olfactory bulb and to the accessory olfactory bulb, whereas there was deeper invasion of the olfactory bulb and olfactory ventricular system with mice infected with standard VSV alone. Correlation between mortality and extent of invasion became more difficult to make from 8 days on, when VSV antigens were found in discrete areas of the brain. By 12 days, few surviving mice contained any detectable VSV antigen in their brains. These results demonstrate that DI particles have potential as therapeutic agents. Also, mortality resulting from VSV-induced encephalitis, although poorly understood, may be determined very early, possibly while the virus is replicating at the site of inoculation.  相似文献   
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