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Summary. A man, 79 years of age, developed a malignant fibrous histiocytoma which arose in relation to a calcifying enchondroma of the distal femur. Radiographs showed a fracture through an intensely calcified bony tumour with no bony destruction. The clinical diagnosis was a dedifferentiated chondrosarcoma. Histology showed an anaplastic sarcoma with calcified tissue showing extensive areas of necrosis and degeneration. No chondrosarcomatous foci were found.
Resumé. Nous rapportons le cas d’un homme de 79 ans, qui a développé un histiocytofibrome malin à partir d’un enchodrome calcifié du fémur distal. L’examen radiologique a montré une fracture au sein d’une tumeur très calcifiée sans association de destruction osseuse. Cette lésion apparaissait cliniquement être un chondrosarcome dédifférencié. Mais l’étude histologique a montré un sarcome anaplasique avec un tissu cartilagineux calcifié présentant des plages étendues de nécrose et de dégénérescence. Il n’y avait pas de foyer chondrosarcomateux visible.


Accepted: 9 November 1996  相似文献   
13.
In order to investigate the influence of respiratory frequency in the measurement of specific airway conductance (sGaw) during non-panting breathing, we examined specific airway conductance using a body plethysmograph (BX-82, Minato) in 20 stable pulmonary emphysema patients and 19 normal control subjects. Our body plethysmograph device can measure sGaw automatically without panting by making various corrections using a 16-bit microcomputer. We measured sGaw first at a flow of 0.5 L/sec during both inspiratory and expiratory ventilatory phases, then the respiratory frequency was changed from 0.5 to 1.0, 1.5 and 2.0 Hz. In normal control subjects sGaw, tidal volume and mouth flow significantly changed by increasing respiratory frequency, and there was a significant correlation between sGaw and mouth flow. In pulmonary emphysema patients, tidal volume decreased significantly by increasing respiratory frequency, and there was a significant correlation between sGaw and tidal volume, but sGaw and mouth flow did not change significantly by increasing respiratory frequency. These results suggest that specific airway conductance is influenced by respiratory frequency, possibly due to the change in tidal volume and mouth flow. It is necessary to standardize respiratory frequencies and mouth flows in the measurement of specific airway conductance during non-panting breathing.  相似文献   
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The mechanism by which prostacyclin acts to prevent in vivo reperfusion injury is still uncertain. This study was therefore undertaken to assess the effect of a stable prostacyclin analogue (OP 41483-alpha-CD [OP]) on oxygen-derived free radicals after heart-lung transplantation. OP was administered to the heart-lung graft through the pulmonary artery for 25 minutes encompassing the reperfusion process. Free radicals were directly measured by electron spin resonance spectroscopy. The radical intensities of pulmonary venous blood were significantly lower in the OP group than in the control group, suggesting that fewer free radicals were generated in the lungs of the OP group. The cardiac and respiratory function were better in the OP group than in the control group. The lung is the primary source of oxygen free radical attack, and the beneficial action of OP on free radical generation is almost exclusively restricted to the lung and does not apply to the heart. This result suggested that OP probably is effective in inhibiting free radical generation from the endothelium.  相似文献   
16.
Malignant peripheral nerve sheath tumors (MPNSTs; malignant schwannomas) rarely occur in the anterior mediastinum, and their prognosis is poor. A 75-year-old man was referred to our hospital for examination of an anterior mediastinal tumor. A computed tomography-guided percutaneous needle biopsy revealed only fibrosis. The tumor was completely excised via a median sternotomy with partial resection of the pericardium and right upper lobe of the lung. Thereafter, the tumor was diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma. At 1 year after the surgery, a distant metastasis was found in the interlobular space between the right middle and lower lobes. The tumor was completely excised via a right posterolateral thoracotomy. Reexamination of the primary and secondary tumors revealed an MPNST. No recurrence was found up to 5 years after the second surgery without adjuvant chemotherapy or radiation therapy. However, he died from multiple lung metastases after 6 years.  相似文献   
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Positron emission tomography (PET) studies on regional cerebral glucose metabolism and [18F]fluorodopa uptake were performed on 3 patients with "pure akinesia without rigidity and tremors", 3 progressive supranuclear palsy (PSP) patients, and 5 patients with Parkinson's disease. The "pure akinesia" and PSP patients showed a marked decrease in glucose metabolism in the frontal cortex and striatum, and a decreased uptake of [18F]fluorodopa in the striatum. While the Parkinson's disease patients had a decreased uptake of [18F]fluorodopa in the striatum but no abnormality in the glucose metabolism. Magnetic resonance imaging (MRI) showed atrophy of the pretectum and dorsal pons in "pure akinesia" and PSP patients, but there was no such abnormality in the Parkinson's disease patients. As described above, patients with "pure akinesia" and PSP patients revealed similar findings on PET and MRI studies, while Parkinson's disease patients showed substantially different results.  相似文献   
19.
When artificial hip or knee joints are implanted in the human body, they release metallic, ceramic, and polymeric debris into the surrounding tissues. The toxicity of the released particles is of two types: chemical, caused by the released soluble ions and monomers, and mechanical, a result of mechanical stimulation produced by the insoluble particles. In this study, the cytotoxicity of particles of TiO2, Al2O3, ZrO2, Si3N4, and SiC for murine fibroblasts and macrophages were examined to evaluate just their mechanical toxicity because these particles are not expected to release soluble metal ions. Different sizes and shapes of TiO2 particles were used to evaluate the effect of size and shape on particle cytotoxicity. The results suggest that the cytotoxicity of ceramic particles does not depend on their chemical species. Cytotoxicity levels were lower than those of corresponding metal ions, indicating that the mechanical toxicity of particles is lower than the chemical toxicity of released soluble ions and monomers. The differences in size did not affect the mechanical toxicity of these particles. The dendritic particles had a higher cytotoxicity level for macrophages than did spindle and spheric particles.  相似文献   
20.
The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease.  相似文献   
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