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1.
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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We developed five monoclonal antibodies against respiratory syncytial virus. Three of these (23A3, 12A4, and 18B2) were used in an indirect fluorescent antibody test, and the results were compared with those of a similar indirect fluorescent test with commercial anti-respiratory syncytial virus serum. The results obtained with antibody 18B2 and commercial anti-respiratory syncytial virus serum were identical, whereas with antibodies 23A3 and 12A4 the incidence of positive identifications was around 50%.  相似文献   
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Needle puncture and other accidents that occur during surgery and other procedures may lead to viral infections of medical personnel, notably by hepatitis C (HCV) and human immunodeficiency virus (HIV), now that hepatitis B can be prevented by vaccination. A new surgical glove called G-VIR, which contains a disinfecting agent for enveloped viruses, has been developed. Herpes simplex type 1 (HSV) was used as a standard enveloped virus in both in vitro and in vivo tests of the virucidal capacity of the glove. Bovine viral diarrhea virus (BVDV) and feline immunodeficiency virus (FIV) were used as models for HCV and HIV, respectively. For in vitro study, a contaminated needle was passed through a glove and residual virus was titrated; for in vivo studies, animals were stuck with a contaminated needle through a glove. Despite variation in virus enumeration inherent in the puncture technique, statistical evaluation showed that infection was reproducibly and substantially reduced by passage through the virucidal layer. For BVDV, the amount of virus passing through the virucidal glove was reduced in 82% of pairwise comparisons with control gloves that lacked the virucidal agent; when plaque counts were adjusted to a common dilution, the median count for the virucidal glove was on the average reduced >10-fold. In experiments in which the proportion of wells infected with FIV was measured, the ratio of TCID(50) values (control glove to G-VIR) was >15, and probably much higher. For HSV, the amount of virus passing through the virucidal glove was reduced in 81% of comparisons with control gloves; the median of adjusted plaque counts was reduced on the average approximately eightfold or ninefold. In vivo tests with FIV and HSV in cats and mice, respectively, found smaller percentage reductions in infection than the in vitro tests but confirmed the virucidal effect of the gloves.  相似文献   
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A simplified and reliable enzyme-linked immunosorbent assay (ELISA) was applied to the detection of serum antibodies against respiratory syncytial virus (RSV). RSV-infected cells were fixed and dried on 96-well microtiter plates and kept at 4 degrees C. The titers of reference sera were determined by endpoint dilution. A linear relation was found between the titers and the logarithm of absorbance values of sera diluted to 1:1,000 (r = 0.93, P less than 0.001). Measurement of RSV antibodies was done by using a single serum dilution (1:1,000) in conjunction with a standard curve. A strong correlation was found between complement fixation and ELISA results (r = 0.89, P less than 0.001). In addition, the ELISA method exhibited higher titers and a greater sensitivity than did complement fixation, although the applicability of the assay is limited with positive serum samples of low titer.  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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Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging.  相似文献   
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