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21.
Solitary fibrous tumor (SFT) of the retroperitoneal space is rare. We report a case of retroperitoneal tumor, diagnosed as SFT. A 69-year-old woman presented with right lower abdominal swelling, and was referred to our hospital with suspicion of right renal tumor. Abdominal ultrasound and computerized tomography (CT) showed a mass (about 15 x 14 x 10 cm) in the right abdomen. The tumor was thought to be right renal rumor, and right radical nephrectomy was performed. In the excised specimen the tumor was not connected to gastrointestinal tract, peritoneum, or right kidney. The histological and immunohistochemical examination of the specimen revealed SFT. The tumor has malignant potential with partially increased mitotic activity and cellularity in the histological examination. The patient is healthy and without evidence of recurrence or metastasis 26 months from surgery.  相似文献   
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OBJECT: The authors have developed a mixture of ethylene vinyl alcohol copolymer (EVAL) and iopamidol, which is dissolved in ethanol, as an alternative solvent to provide a safe means of embolizing arteriovenous malformations (AVMs). METHODS: A two-stage delivery technique is required to prevent premature precipitation in the catheter when using this material: the catheter is first infused with 30% ethanol and this is followed by the delivery of the EVAL-ethanol mixture. Acute angiographic changes were analyzed after superselective delivery of dimethyl sulfoxide (DMSO) and 30% ethanol into the renal artery of rabbits. Histological changes following the embolization of the renal artery achieved using the EVAL-ethanol mixture were recorded at 1 hour and at 2 and 16 weeks after the procedure. Although DMSO always produced severe, rapidly progressive vasospasm in the renal artery during a 1- to 60-minute postinfusion, 30% ethanol did not. Microscopically, the lumens of embolized vessels examined 1 hour after embolization with EVAL-ethanol appeared to be filled with EVAL sponges, leaving almost no open spaces. The space between the EVAL sponges and the inner surface of the vessels was filled with fresh thrombus. In the vessel walls of specimens examined 2 weeks after embolization there was no or a slight inflammatory reaction. Scattered in the EVAL sponges were almost equal numbers of neutrophilic granulocytes and mononuclear cells, indicative of a mild inflammatory response. In specimens examined 16 weeks postembolization, the changes noted at 2 weeks were intensified. There was no definite histopathological evidence of mural hemorrhage, perivascular extravasation of the mixture, or perivascular hemorrhage in any specimen that was examined. CONCLUSIONS: Although the degree of permanence of this embolization material is yet unknown, the mixture was easy to handle, and appeared safe and effective for AVM embolization. Its nonadhesive characteristic and its ability to be infused by repeated injections make it an attractive alternative to currently available materials. The good results obtained in this study led us to undertake a clinical trial, the results of which are contained in a companion article in this issue of the Journal of Neurosurgery.  相似文献   
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Laparoscopic spleen-preserving distal pancreatectomy (LSDP) with conservation of the splenic vessels is gaining acceptance as a reliable treatment for selected patients with low-grade malignant tumors of the pancreas in adults. The operation requires advanced laparoscopic skills to safely divide the fine branches of the splenic vessels. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels is rarely reported in children. We describe a 12-year-old girl with solid pseudopapillary tumor in the body of the pancreas that was successfully treated with LSDP, preserving the splenic vessels. The postoperative course was uneventful, and the functional and aesthetic results were satisfactory. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels may be a safe and feasible treatment option for children with pancreatic disease.  相似文献   
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Bioartificial renal tubule devices (BTD) use cell therapy to improve conditions commonly observed in recipients of artificial kidneys for treatment of kidney diseases. We previously reported significant improvement of the condition of acute kidney injury (AKI) animals after treatment with BTD prepared with lifespan-extended human renal proximal tubular cells (hRPTEC). However, a major obstacle to use of BTD for patients is their biological safety, because hRPTEC are cultured in medium containing fetal calf serum. To establish the biological safety of BTD, we prepared BTD with lifespan-extended hRPTEC cultured in a newly developed serum-free medium and compared these with BTD prepared with hRPTEC cultured in serum-containing conventional medium. Lifespan-extended hRPTEC cultured in serum-free medium (hRPTEC-SFM) can proliferate similar to hRPTEC cultured in serum-containing conventional medium (hRPTEC-CM). Comparison of leakage and of reabsorption of small molecules for BTD prepared with hRPTEC-SFM (BTD-SFM) with those for our previous BTD prepared with hRPTEC-CM (BTD-CM) showed transportation in these two types of BTD was almost identical. When AKI goats were treated with BTD-SFM for 26 h, increase of survival time and reduction of cytokine expression in blood cells were almost same as for AKI goats treated with BTD-CM. Quantification of the expression of some genes of hRPTEC in BTD revealed significant changes during BTD treatment for AKI goats. In conclusion, lifespan-extended hRPTEC-SFM work as well as hRPTEC-CM, and the biological safety of BTD for patients could be elevated without loss of function by preparation from hRPTEC-SFM.  相似文献   
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A 63 year-old female presented with dyspnea on exertion. Her chest X-ray showed cardiomegaly, and right ventricular overload and tricuspid regurgitation were detected. Her pulmonary ventilation and blood flow scintigraphy findings were suspicious of pulmonary vascular disease; the diagnosis was pulmonary hypertension and bilateral branch pulmonary artery stenosis. After the inflammation settled, the stenotic bilateral branch pulmonary artery was reconstructed with a prosthetic vessel and the pulmonary pressure normalized immediately. A resected specimen revealed that the stenotic changes were from Takayasu's disease. The patient's postoperative course was uneventful, and pulmonary ventilation and blood scintigraphy returned to an almost normal range. At follow-up 5 years and 6 months after the operation, there was no evidence of pulmonary artery disease (eg, stenosis and/or ischemia) or of any change in the central vessels of the retina, the so-called Takayasu's retinopathy.  相似文献   
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The gracile axonal dystrophy (gad) mutation in Uch-l1, the gene encoding the ubiquitin carboxy-terminal hydrolase isozyme L1 (UCH-L1), causes selective dying back degeneration of dorsal root ganglion neuron in the medulla oblongata along with progressive sensory-motor ataxia. Axonal spheroids are observed within degenerating axons, and their contents may illuminate the pathogenic mechanisms leading to neurodegeneration in gad mice. To analyze changes in negatively charged lipid molecules in dystrophic axons of gad mice, we performed matrix-assisted laser desorption/ionization (MALDI)-imaging mass spectrometry (IMS), electron microscopy, and fluorescence immunohistochemistry on tissue sections from gad and wild-type mouse medulla. MALDI-IMS revealed that m/z 806.68 and 822.68 molecules, assigned to sulfatide (ST) C18:0 and ST C18:0(OH), respectively, were concentrated in the dorsomedial medulla. This spatial distribution overlapped significantly with that of axonal spheroids. Immunostaining revealed that spheroids accumulated myelin and lymphocyte protein, a known ST binding protein. Sulfatides with short-chain fatty acids (C16–C20) are generally localized in intracellular vesicles; therefore, ST C18:0 accumulation may reflect intracellular vesicle aggregation within spheroids. Ubiquitin system disruption apparently alters lipid metabolism, membrane organization, protein turnover, and axonal transport. Changes in membrane organization, particularly STs within lipid rafts, may disrupt cellular signaling pathways necessary for neuronal viability.  相似文献   
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