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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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Engineering tissues in bioreactors is often hampered by disproportionate tissue formation at the surface of scaffolds. This hinders nutrient flow and retards cell proliferation and tissue formation inside the scaffold. The objective of this study was to optimize scaffold morphology to prevent this from happening and to determine the optimal scaffold geometric values for connective tissue engineering. After comparing lyophilized crosslinked collagen, compression molded/salt leached PEGT/PBT copolymer and collagen-PEGT/PBT hybrid scaffolds, the PEGT/PBT scaffold was selected for optimization. Geometric parameters were determined using SEM, microcomputed tomography, and flow permeability measurements. Fibroblast were seeded and cultured under dynamic flow conditions for 2 weeks. Cell numbers were determined using CyQuant DNA assay, and tissue distribution was visualized in H&E- and Sirius Red-stained sections. Scaffolds 0.5 and 1.5 mm thick showed bridged connected tissue from top-to-bottom, whereas 4-mm-thick scaffolds only revealed tissue ingrowth until a maximum depth of 0.6-0.8 mm. Rapid prototyped scaffold were used to assess the maximal void space (pore size) that still could be filled with tissue. Tissue bridging between fibers was only found at fiber distances < or =401 +/- 60 microm, whereas filling of void spaces in 3D-deposited scaffolds only occurred at distances < or =273 +/- 55 microm. PEGT/PBT scaffolds having similar optimal porosities, but different average interconnected pore sizes of 142 +/- 50, 160 +/- 56 to 191 +/- 69 microm showed comparable seeding efficiencies at day 1, but after 2 weeks the total cell numbers were significantly higher in the scaffolds with intermediate and high interconnectivity. However, only scaffolds with an intermediate interconnectivity revealed homogenous tissue formation throughout the scaffold with complete filling of all pores. In conclusion, significant amount of connective tissue was formed within 14 days using a dynamic culture process that filled all void spaces of a PEGT/PBT scaffolds with the following geometric parameters: thickness 1.5-1.6 mm, pore size range 90-360 microm, and average interconnecting pore size of 160 +/- 56 microm.  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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Summary Capillary gas chromatographic (GC) methods using sulphur and mass selective detection for the qualitative and quantitative determination of tetrahydrophtalimide (THPI) and 2-thiothiazolidine-4-carboxylic acid (TTCA), urinary metabolites of the fungicide captan in rat and humans, were developed. Urinary detection limits were 2.7 g/l for THPI and 110 g/l for TTCA. Intraperitoneal and oral administration of captan to rats resulted in a 48-h cumulative urinary excretion of THPI of 1%–2% and 3%–9% of the dose, respectively. Cumulative urinary excretion of TTCA over 48 h ranged from 2% to 5% of the captan dose for the respective routes of administration. In urine of non-exposed human subjects, neither THPI nor TTCA could be detected. In urine of fruit-growers who were occupationally exposed to captan, both THPI and TTCA could be detected. Based on these results, THPI and TTCA are proposed as promising parameters for the biological monitoring of occupational exposure to captan.  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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Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.  相似文献   
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