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41.
A 54-year-old man was seen with a fracture of the left femur. Plain radiographs revealed a 40-mm lytic centromedullary lesion. Magnetic resonance T1- and T2-weighted sequences showed high and low signals. After stabilization of the fracture, the tumor was removed followed by reconstruction with a vascularized fibula. The pathological examination demonstrated proliferation of non atypical CD34 and CD31 positive epithelioid cells with few lumens, accompanied by abundant fibrous stroma, sometimes masking tumor cells. Satisfactory motion was achieved with no recurrence at 20 months follow-up. Bone hemangioendothelioma can simulate metastasis and must be distinguished by immunohistochemistry. Prognosis is a subject of debate as the tumor is considered to exhibit intermediate malignancy by some authors while other consider it to be a malignant tumor.  相似文献   
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OBJECTIVE: Converging evidence implicates prefrontal circuits in the pathophysiology of bipolar disorder. Proton spectroscopy studies performed in adult bipolar patients assessing prefrontal regions have suggested decreased levels of N-acetylaspartate (NAA), a putative marker of neuronal integrity. In order to examine whether such abnormalities would also be found in younger patients, a 1H spectroscopy study was conducted that focused on the dorsolateral prefrontal cortex of children and adolescents with bipolar disorder. METHOD: The authors examined the levels of NAA, creatine plus phosphocreatine, and choline-containing molecules in the left dorsolateral prefrontal cortex of 14 bipolar disorder patients (mean age=15.5 years, SD=3, eight female) and 18 healthy comparison subjects (mean age=17.3, SD=3.7, seven female) using short echo time, single-voxel in vivo 1H spectroscopy. Absolute metabolite levels were determined using the water signal as an internal reference. RESULTS: Bipolar patients presented significantly lower NAA levels and a significant inverse correlation between choline-containing molecules and number of previous affective episodes. No differences were found for other metabolites. CONCLUSIONS: These findings suggest that young bipolar patients have decreased NAA levels in the dorsolateral prefrontal cortex, similar to what was previously reported in adult patients. Such changes may reflect an underdevelopment of dendritic arborizations and synaptic connections. These neuronal abnormalities in the dorsolateral prefrontal cortex of bipolar disorder youth are unlikely to represent long-term degenerative processes, at least in the subgroup of patients where the illness had relatively early onset.  相似文献   
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Using serologic and molecular methods, 45 nasopharyngeal carcinoma (NPC) patients were typed for HLA class I and class II and were compared to 100 unrelated normal Tunisians. Our results showed that the antigen frequency of HLA-B13 and allelic frequencies of DRB1*03, DRB1*15 were significantly higher in the NPC patients than in the control group (15.5 vs. 4; 26.4 vs. 11.5, and 14.4 vs. 6.5%, respectively) probably indicating a positive association with NPC. Moreover, we observed that HLA-A23 was absent in our NPC sample and was present in 18% of normal controls, and HLA-DRB1*11 was less frequent among the patients compared to the controls (5.5 vs. 14%) suggesting a protective effect of this association with NPC.  相似文献   
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PURPOSE: To compare gemcitabine and cisplatin (GC) with mitomycin, ifosfamide, and cisplatin (MIC) chemotherapy in patients with stage IIIB (limited to T4 for pleural effusion and N3 for supraclavicular lymph nodes) or stage IV non-small-cell lung cancer (NSCLC). The end points were the evaluation of quality of life (QoL), response rates, survival, and toxicity. PATIENTS AND METHODS: Three hundred seven patients were randomized to receive either gemcitabine 1,000 mg/m(2) on days 1, 8, and 15 plus cisplatin 100 mg/m(2) on day 2, every 28 days, or mitomycin 6 mg/m(2), ifosfamide 3,000 mg/m(2), and mesna on day 1 plus cisplatin 100 mg/m(2) on day 2, every 28 days. The whole-blood cell count was repeated on day 1 in both arms and weekly in the GC arm before each gemcitabine administration. RESULTS: No major differences in changes in QoL were observed between the two treatment arms. The objective response rate was 38% in the GC arm compared with 26% in the MIC arm (P =.029). The median survival time was 8.6 months in the GC arm and 9.6 months in the MIC arm (P =.877, log-rank test). Grade 3 and 4 thrombocytopenia was significantly worse in the GC arm (64% v 28%, P <.001), whereas grade 3 and 4 alopecia was reported more commonly in the MIC arm (39% v 12%, P <. 001). CONCLUSION: We report an increased response rate without changes in QoL and a similar overall survival, time to progression, and time to treatment failure for the GC when compared with the MIC regimen in the treatment of advanced NSCLC.  相似文献   
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Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia.  相似文献   
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OBJECTIVES: The aim of our study is to evaluate anatomic regeneration and metabolic derangement of the liver after major resection in dogs. METHODS: This is an experimental study on 9 dogs; we divided the dogs in two groups: the first group (5 dogs) underwent at one go major hepatectomy (90% of the liver).The second group (4 dogs) underwent successively a resection of 75% of the liver and a second resection of 90% of the restored liver six months later. All dogs underwent a metabolic and morphologic studies of the liver and of their kidney function. RESULTS: In the first group; all dogs which underwent 90% hepatic resection died 48 hours after the surgical resection of hepatic insufficiency. The ultra microscopic study showed the role of portal hypertension in hepatic degeneration on the first group. In the second group, the dogs survived the first resection, and our study shows a regeneration of the liver after resection and sub normal hepatic function. CONCLUSION: The liver is able to regenerate after minimally resection but major resection must be done by successively resection to avoid hepatic dysfunction, but the time between resection must be evaluate later.  相似文献   
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