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1.
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course.  相似文献   
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BACKGROUND: Haemophilus influenzae (H. influenzae) is the most frequent bacterial pathogen of respiratory tract infections in children. Detection of antimicrobial susceptibility of H. influenzae is necessary for institution of appropriate antibiotic treatments. METHODS: A total of 281 strains of H. influenzae isolated from sputum samples of 281 pediatric patients with respiratory tract infections were recruited for study. Antibiotic susceptibility was determined by assessing minimum inhibitory concentrations (MIC) of antimicrobial agents. MIC were measured by utility of Agar dilution susceptibility test. RESULTS: Of the total, 38 (13.5%) strains produced beta-lactamase (BLP), 56 (19.9%) strains were beta-lactamase non-producing, ampicillin resistant (BLNAR). The overall resistant proportion to ampicillin was 33.4%. The data indicated that sulbactam/ampicillin, cefotaxime, ceftriaxone and cefditoren are effective against BLP strains. In addition, a high prevalence of BLNAR H. influenzae strains was identified, with an overall isolation rate of 19.9%. Those strains mainly demonstrated intermediate level to ampicillin (ampicillin-MIC 相似文献   
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Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
4.
Alterations in lung superoxide dismutase (SOD) isozymes after exposure of mice to mercury vapor were examined. Inhalation of mercury vapor (10 mg/m(3)) for 1 h by mice resulted in a higher accumulation of mercury in the kidney and lung compared to other organs, at 1 h after exposure. Under these conditions marked enhancement of protein content in bronchoalveolar fluid (BALF), attributed to lung injury, was observed. Exposure to mercury vapor caused a significant increase in the pulmonary Cu,Zn-SOD activity (1.32-fold at 48 h) whereas Mn-SOD activity was suppressed to 82% of the control level, suggesting different sensitivity to the metal inhalation. The selective induction of Cu,Zn-SOD protein (1.79-fold at 48 h) was confirmed by immunoblot analysis with polyclonal antibodies against these isozymes. These observations suggest that the selective induction of Cu,Zn-SOD at the translational level appears to occur as an initial defense against mercury-promoted oxidative stress.  相似文献   
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The lipid cell variant of urothelial carcinoma is a rare variant of urinary bladder cancer, comprised of lipoblast‐like cells. In this report, we describe a case of the lipid cell variant of aggressive urothelial carcinoma. A 78‐year‐old man was admitted to the hospital because of gross hematuria. On cystoscopy, an ulcerative lesion, non‐papillary architecture, was observed in the lateral wall of the bladder. Transurethral resection was performed. Histopathological findings of the bladder tumor indicated neoplastic cells forming irregular solid nests and sheets. Lipoblast‐like neoplastic cells that had eccentric nuclei and cytoplasmic vacuoles were observed, not only in the resected specimen, but also in urine samples. On mucin histochemistry, the tumor cell cytoplasm contained no neutral or acidic mucus. The lipoblast‐like cells were positive for cytokeratins (AE1/AE3, CK7) and adipophilin, known as a protein associated with neutral lipid synthesis. In general, it is difficult to prove the existence of intracytoplasmic lipid in formalin‐fixed paraffin‐embedded materials. This is the first report in which the presence of lipid in vacuoles of the lipid cell variant has been verified by immunohistochemistry.  相似文献   
8.
Chromophobe renal cell carcinoma (RCC) accounts for approximately 5% of renal epithelial neoplasms. Multiple and/or bilateral chromophobe RCCs in an individual are generally rare but frequently occur in patients with Birt–Hogg–Dubé syndrome (BHDS) and in patients with tuberous sclerosis complex (TSC). The responsible genes in both BHDS and TSC act as tumor suppressors. Therefore, it seems that some genetic backgrounds are required for the generation and progression of multiple chromophobe RCCs. Here, we report a case of multiple and bilateral chromophobe RCCs along with several small‐sized capsular angiomyolipomas known as ‘capsulomas’ in a 39‐year‐old woman who had neither a particular medical history nor specific gene mutation. There has been no report of sporadic multiple chromophobe RCCs and ‘capsulomas’ developing in a patient without genetic features, having potential for novel genetic variation.  相似文献   
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