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Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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Functional imaging is ideally suited to monitoring the effect of specific therapy on disease processes. In this pilot study five patients with AIDS and Pneumocystis carinii pneumonia (PCP) were imaged with Indium-111 labelled pooled human immunoglobulin (111In-HIG) during infection and after therapy for PCP. The lung activity of t t tln-HIG, measured as a lung/heart ratio, was calculated in a study performed during infection with PCP and after therapy. In all five patients the lung/heart ratio of t t 1ln-HIG was reduced after treatment. The mean reduction in heart/lung ratio was 27% (range 12%-53%). If these results are confirmed by a larger study, 11In-HIG will be useful in monitoring the response of PCP to therapy in patients with AIDS.  相似文献   
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The La antigen is a nuclear protein that is one of the major target antigens of autoantibodies found in the sera of patients with primary Sj?gren's syndrome. The formation of such autoantibodies is therefore likely to reflect the basic immunopathogenesis of this disorder. A recombinant DNA strategy has been used to examine the La protein for sequences that encode autoimmunizing B cell epitopes. We have isolated and characterized a 1.2-kb-long cDNA from a human liver cDNA library encoding a region of the La protein; this region contains 296 amino acids, including the C terminus. A sub-library of recombinant DNA in the expression vector pEX was made from portions of the La cDNA. Individual fusion proteins were tested by immunoblotting and enzyme-linked immunosorbent assay for their ability to react with anti-La autoantibodies contained in sera from patients with Sj?gren's syndrome. In this way, we have identified at least three distinct epitopes in the C-terminal half of the La protein. Every anti-La serum tested contained antibodies against all three of the antigenic regions identified. Furthermore, most of the sera display similar ratios between the titers of antibodies with the three kinds of specificity. Our data suggest that the production of anti-La autoantibodies may be antigen driven.  相似文献   
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A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.   相似文献   
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目的对十年前后精神分裂症患者用药情况的变化进行调查分析.方法对十年前后两个五年段的各500份符合精神分裂症诊断标准的病历进行回顾性调查,并对各项指标进行对比分析.结果两组折算用药剂量经t检验差异无显著性(P>0.05);两组合并用药、合并抗胆碱药及疗效经χ2检验差异有显著性(P<0.01);十年后非典型抗精神病药物氯氮平在临床上的应用比例明显增大并上升为首位.结论十年前后两组抗精神病药的应用发生了明显变化,疗效好、副作用轻的非典型抗精神病药的应用比例明显增加.  相似文献   
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