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111.
We report a case of renal hemangiopericytoma which was incidentally discovered by ultrasonography at a health screening. A 58-year-old man was admitted to our hospital for close examination of the renal tumor. Computed tomography revealed the left renal tumor, 60 x 50 mm in size, which was well enhanced with contrast medium. Magnetic resonance imaging revealed an isointensity mass (T1-weighted) and high-intensity mass (T2-weighted) at the left kidney. Radical nephrectomy was performed on suspicion of left renal cell carcinoma. Histopathological examination revealed renal hemangiopericytoma. The present case is the 7th in the Japanese literature.  相似文献   
112.
We report successful anesthetic management of a 1.7-kg premature infant who underwent thoracoscopic thoracic duct ligation under general anesthesia. She was born at 30 weeks gestation with birth weight of 1,546 g and was suffering from respiratory distress due to persistent right chylothorax for two months after birth. Chest tube drainage, fasting and intrapleural fibrin glue did not reduce her right chylothorax. Thoracoscopic thoracic duct ligation was scheduled on her day 64 under general anesthesia. The tracheal tube end was placed in the midtrachea and carbon dioxide was insufflated into the operative side of the thorax. During thoracoscopy her left lung was ventilated with the right lung pressed with spatulaes, but her respiratory status did not deteriorate so much despite of unilateral ventilation. We speculate that, due to massive right chylothorax, her pulmonary blood flow had already shifted to the left lung, therefore intraoperative substantial left unilateral lung ventilation exerted minimal effect on her respiratory status. The operation was successful and she was weaned from the ventilator on the following day.  相似文献   
113.
A 50-year-old woman presented with rare multiple dissecting aneurysms that appeared first in the anterior cerebral artery (ACA) and shortly afterwards in the vertebral artery (VA). She initially suffered sudden motor weakness in the left lower limb due to acute brain infarction. Angiography revealed diffuse string sign in the right ACA. Conservative treatment resulted in resolution of the deficits. Follow-up angiography performed 1 year later revealed recovery of the ACA stenosis. Fourteen days later, she complained of sudden headache and became comatose. Computed tomography showed diffuse subarachnoid hemorrhage. Angiography revealed a new right VA dissecting aneurysm involving the posterior inferior cerebellar artery (PICA). The orifice of the dissection was not apparent in the operative field and the dissection extended to the median. The patient underwent extracranial right VA ligation, clipping of the proximal PICA, and revascularization between the right occipital artery and distal PICA. Her postoperative course was uneventful and she was discharged without neurological deficits. VA dissecting aneurysms involving the PICA without evident orifice or extending over the median can be treated by extracranial ligation with clipping of the PICA, followed by revascularization.  相似文献   
114.
An 88-year-old woman presented with a supratentorial primitive neuroectodermal tumor (PNET) manifesting as disturbance of consciousness and left hemiplegia. Magnetic resonance imaging showed a large mass lesion in the right frontotemporal region. She underwent biopsy of the lesion that confirmed the diagnosis of PNET. Her poor condition only allowed chemotherapy with methyl 6-[3-(2-chloroethyl)-3-nitrosoureido]-6-deoxy-alpha-D-glucopyranoside (MCNU), vincristine, and prednisolone to be performed. The patient died approximately 6 months after diagnosis due to enlargement of the tumor. Supratentorial PNET is a rare tumor, especially in adults. Multimodal therapy consisting of gross total or subtotal resection, radiation therapy, and chemotherapy is generally considered necessary for patients with supratentorial PNET. However, the condition of each patient should be considered in determining the therapeutic plan, especially in the case of extremely aged patients, since supratentorial PNET is malignant and long-term survival is rare despite aggressive treatment.  相似文献   
115.
Nakano Y  Yokota A 《Journal of UOEH》2005,27(4):349-358
In the 1980s, it was demonstrated that human tumors had tumor antigens, and immune responses against human tumor antigens were induced. These days, various new immunotherapies are attempted to enhance immune responses against tumors and prevent tumor growth and progression. Nonetheless, it is difficult to reject tumors by only immune responses. One of the reasons is an immunosuppressive state in tumor-bearing hosts. It is considered that an immunosuppressive state is induced by various factors from the tumor side or host side, but the precise mechanism is not clear. When we consider the effective immune responses against tumors, we need to make clear and improve the immunosuppressive state in the tumor-bearing hosts.  相似文献   
116.
BACKGROUND: Although craniopharyngiomas have a histologically benign nature, their treatment can be difficult. The correlation among clinical, proliferative, and immunohistologic features of female sex hormone receptors was determined in craniopharyngiomas to analyze whether they influence the growth of the tumor. METHODS: The study subjects were 43 patients with previously untreated craniopharyngioma who underwent surgery at our department over the past 15 years. Serial tissue sections were immunostained with the antibodies against estrogen receptor (ER), progesterone receptor (PR), and Ki-67. RESULTS: The Ki-67 labeling index was significantly higher in patients with regrowth (7.8%) than without regrowth (3.9%). ER and PR were detected in 9 of 30 (30%) craniopharyngiomas, and the incidence of postoperative tumor regrowth was significantly higher in patients negative for ER and PR (29%) than in those positive for both receptors (11%). CONCLUSIONS: A high Ki-67 labeling index suggests a high possibility of tumor regrowth, and the presence of ER and PR is suggestive of a high tissue differentiating potential. ER and PR assay may be useful for determining the indication for additional radiation therapy in craniopharyngioma patients treated by incomplete resection.  相似文献   
117.
Osteogenic potential of primed periosteum graft in the rat calvarial model   总被引:3,自引:0,他引:3  
Repair of bone defects remains a major concern in plastic and maxillofacial surgery. Based on modern concepts of tissue engineering, periosteum has gained attention as a suitable osteogenic material. We tested the hypothesis that surgically released and immediately repositioned periosteum would exhibit high osteogenic capacity upon grafting in a rat calvarial defect. Seven days after periosteum was released from the tibia and immediately repositioned, the "primed periosteum graft" (PPG; n = 15) was placed into a critical-sized defect of rat calvaria and the process of bone formation was evaluated histologically, immunohistologically, and radiographically at 7, 14, and 21 days after grafting. Findings were compared with a nonprimed periosteal graft (NPG; n = 15).Endochondral ossification was observed in both the PPG and NPG. The PPG showed higher expression of proliferative cell nuclear antigen, bone morphogenetic protein, and vascular endothelial growth factor than the NPG. Three-dimensional radiographic examination revealed significantly increased bone formation in the PPG than in the NPG (P < 0.01). These findings suggested that surgical stimulation of the periosteum enhanced the osteogenic potential of periosteal cells. This method may be suitable for the clinical repair of bone defects.  相似文献   
118.
Hypersensitivity to mosquito bites (HMB) is known to be an allergic reaction and also a skin symptom in some cases of natural killer cell leukemia/lymphoma associated with Epstein-Barr virus (EBV) infection. We describe a patient who had suffered from HMB for 5 years, and subsequently developed mantle cell lymphoma (MCL), which resembled chronic lymphocytic leukemia in the early phase. EBV monoclonality was not detected in lymph nodes by Southern blotting. Serum levels of interleukin-4 and IgE were increased, but they decreased and HMB disappeared when MCL was predominant. We consider that HMB may be a potential sign of MCL.  相似文献   
119.
120.
Insulin-like growth factor (IGF), hepatocyte growth factor (HGF), and heparin-binding epidermal growth factor-like growth factor (HB-EGF) are cardiogenic and cardiohypertrophic growth factors. Although the therapeutic effects of IGF and HGF have been well demonstrated in injured hearts, it is uncertain whether natural upregulation of HB-EGF after myocardial infarction (MI) plays a beneficial or pathological role in the process of remodeling. To answer this question, we conducted adenoviral HB-EGF gene transduction in in vitro and in vivo injured heart models, allowing us to highlight and explore the HB-EGF-induced phenotypes. Overexpressed HB-EGF had no cytoprotective or additive death-inducible effect on Fas-induced apoptosis or oxidative stress injury in primary cultured mouse cardiomyocytes, although it significantly induced hypertrophy of cardiomyocytes and proliferation of cardiac fibroblasts. Locally overexpressed HB-EGF in the MI border area in rabbit hearts did not improve cardiac function or exhibit an angiogenic effect, and instead exacerbated remodeling at the subacute and chronic stages post-MI. Namely, it elevated the levels of apoptosis, fibrosis, and the accumulation of myofibroblasts and macrophages in the MI area, in addition to inducing left ventricular hypertrophy. Thus, upregulated HB-EGF plays a pathophysiological role in injured hearts in contrast to the therapeutic roles of IGF and HGF. These results imply that regulation of HB-EGF may be a therapeutic target for treating cardiac hypertrophy and fibrosis.  相似文献   
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