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91.
We report a case of cutaneous atypical mycobacteriosis in a 12-year-old healthy girl due to Mycobacterium avium. The cutaneous symptoms were three well-defined subcutaneous nodules on both buttocks and on the posterior surface of the left thigh. One had a fistulous opening on the skin surface. Histopathological examination revealed epithelioid cell granulomas surrounded by dense lymphocytic infiltration and acid-fast bacteria were seen with modified periodic acid-carbol fuchsin staining. Using Ogawa's medium at 37°C, acid-fast bacteria were isolated from the biopsied specimen and identified by the DNA-DNA hybridization method as Mycobacterium avium. In drug susceptibility test, these were resistant to all antituberculous drugs. Oral administration of minocycline 100 mg/day for two months had little effect on the two remaining lesions, which were therefore excised. Based upon reported cases of Mycobacterium avium complex, we considered that our pediatric patient with multiple intradermal or subcutaneous nodules on the buttocks and the thigh exhibited the characteristic symptoms of M. avium infection.  相似文献   
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93.
Cerebrovascular complications of meningitis have been extensively documented in the literature. It is little known, however, that paroxysmal, devastating, and potentially fatal complications can occur when the early signs of infection are subtle and missed. We describe the clinical course and neuropathological findings of the occurrence of brain infarctions during two atypical clinical courses of meningitis. In one patient, it was due to Serratia marcescens detected only by an autopsy specimen, and in the other, it was due to Aspergillus detected by a surgical biopsy. Death followed multiple, extensive, and progressively multiplicative infarctions in the basal ganglia, brainstem, and cerebral cortices. Autopsies revealed that the infarctions were caused by severe inflammatory change in the vascular walls, mainly of the arteries of the skull base, including the basilar and carotid arteries. Thrombus formation was also recognized in the lumen of several arteries. A number of characteristic Aspergillus hyphae were recognized in the arterial wall of one patient. Meningitis, which may be associated with severe vasculitis and lead to cerebral infarction, should be considered in the differential diagnosis of these conditions. Early diagnosis and initiation of vigorous therapy should be stressed for therapeutic success.  相似文献   
94.
Acute pulmonary thromboembolism is a frequently lethal and acute-onset in-hospital complication after surgery. Absolute indications for surgical embolectomy are acute massive pulmonary embolism with deep shock, refractory circulatory collapse, and continuous hypoxemia. Although thrombolytic therapy is indicated for patients with pulmonary thromboembolism with right ventricular overload, it is contraindicated for patients after major surgery or with stroke due to the high risk of rebleeding. Therefore surgical embolectomy should be considered in those patients. Pulmonary embolectomy relieves the right ventricular overload, and immediate restoration of right ventricular function contributes to the recovery of hemodynamics. A recent study revealed improved outcome for massive pulmonary embolism with early diagnosis with multidetector-row computed tomography, risk stratification using echocardiography, and surgical embolectomy. Surgical pulmonary thromboembolectomy should be considered for critically ill patients with massive pulmonary thromboembolism.  相似文献   
95.
RATIONALE AND OBJECTIVE: The advantage of a higher static magnetic field for functional MRI has been advocated; however, the observed advantage varies. The aim of this study was to evaluate the effect of increasing static magnetic field strength on the task-related increase in blood oxygenation level-dependent (BOLD) signal and residual noise with visual stimuli of different frequencies, which may enable better comparisons of results of different MRI scanners. MATERIALS AND METHODS: Eight right-handed healthy volunteers were presented checkerboard stimuli flickering at 5 different frequencies up to 8 Hz. Field strengths of 3 T or 1.5 T were used to measure frequency-dependent signal changes in the primary visual area. Regression analysis was performed for the signal increase and the "noise," which was defined by the root mean of squares of the residual signal fluctuation. These values were compared and their relationship was analyzed. Imaging parameters were identical except for the use of a 25% shorter echo time using 3 T. RESULTS: The frequency-dependent increase in BOLD signal using 3 T was twice that using 1.5 T. In contrast, the ratio of noise values that reflect time-course signal fluctuation (3 T/1.5 T) was only 0.88. There was large individual variance in these values, but the slope and noise values were linearly related using either field strength. The contrast-to-noise ratio using 3 T was 2.3 times higher than that using 1.5 T. CONCLUSION: There was a greater-than-linear increase in the contrast-to-noise ratio compared with the increase of field strength, demonstrating an advantage of using higher field strengths in fMRI studies.  相似文献   
96.
Liver metastasis of breast cancer is considered a generalized disease, and surgical treatment is rarely discussed. Thirty-four patients who underwent 35 hepatectomies for liver metastases of breast cancer between 1985 and 2003 were analyzed. The median interval between the breast surgery and relapse in the liver was 1.9 years (0–20 years). The liver was the first site of recurrence in 25 patients. Fifteen clinicopathologic factors were evaluated using univariate and multivariate analyses to predict survival after hepatic resection. No patients died because of the surgery. The median survival was 36 months (1 month to 20 years). The overall and disease-free 5-year survival rates after hepatectomy for breast metastases were 21% and 16%, respectively. Four patients survived more than 5 years. The presence of extrahepatic recurrence prior to hepatectomy was the only significant prognostic factor according to the analyses, and the 5-year survival rate of patients without extrahepatic disease was 31%. No patient who had hilar lymph node metastasis survived more than 5 years. In the absence of extrahepatic recurrence, surgical resection of liver metastasis from breast cancer can offer an acceptable prognosis and should not be avoided in selected patients.  相似文献   
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98.
Cyclin G1 (CG1) was identified as a p53-transactivated target gene, and yet its physiological and pathological roles have been unclear. Here, we demonstrate that CG1 is translocated from cytoplasm to the nuclei of neurons in response to variety of injuries. In the normal matured rodent brain, CG1 immunoreactivity was hardly observed; however, some brain injuries exhibited intense CG1 immunoreactivity in the nuclei of the damaged neurons. Transient common carotid artery occlusion (CCAO) in the gerbil showed strong CG1-like immunoreactivity in the hippocampal CA1 neurons, and permanent middle cerebral artery occlusion (MCAO) in the mouse showed strong CG1-like immunoreactivity in the nuclei of neurons located in the ischemic brain regions. TUNEL staining did not exactly overlap with the CG1-positive cells, but overlapped highly with Fluoro-Jade B staining, a degeneration marker. Brain trauma caused by knife cut, cold injury, and kinate injection also showed CG1 accumulation in the neuronal nuclei located near the injury site. These observations were obtained in p53-deficient mice as well, suggesting that the accumulation of CG1 in the injured neurons is p53-independent. A similar nuclear translocation of endogenous CG1 was confirmed in a primary culture of cortical neurons when a toxic level of N-methyl-D-aspartate (NMDA) was applied. These results demonstrate that nuclear translocation of CG1 from cytoplasmic region occurs in damaged and degenerating neurons in a p53-independent manner, and the CG1 nuclear staining could be a good marker for the neurons received fatal damages.  相似文献   
99.
The incidence of hepatic venous complications in partial liver transplantation is more frequent than that in whole liver transplantation. There are no reports of a surgical strategy for hepatic venous outflow block (HVOB) after living-donor liver transplantation. HVOB was diagnosed when the pull-through pressure gradient across the anastomotic site was over 5 mm Hg. Reoperation for venous anastomosis was performed if the angioplasty was unsuccessful. After dissection around the hepatic venous anastomotic site, a patch venoplasty of the anastomosis was performed. When the inferior vena cava was constricted, venoatrial anastomosis was performed. In 6 years, 5 of 223 patients experienced HVOB. Balloon angioplasty was successfully performed in two patients, a patch venoplasty of the anastomosis in two, and venoatrial anastomosis in one. In all patients, the ascites stopped. HVOB must be diagnosed as soon as possible with Doppler ultrasound and venography. Prompt surgical revision can salvage the grafts.  相似文献   
100.
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