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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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Razin BV Inzhevatkin EV Nefedova VV Egorova AB Kazbanov VI Nefedov VP 《Bulletin of experimental biology and medicine》2001,131(6):568-569
We studied the effects of cis-dichlorodiammine platinum (II) on different pathways of cell death in cultured Ehrlich ascites carcinoma in vitro and on subsequent growth of transplanted tumor in vivo. One-hour incubation with the cytostatic modulated apoptosis in cell culture. However, exposure of cell culture to a minimal effective concentration of cis-platinum(II)diammine dichloride promoted the growth of transplanted tumor. 相似文献
4.
Attachment of M. pneumoniae to glass was quantitated in an experimental system enabling the settling down of [3H]palmitic acid-labeled cells onto glass cover slips. Attachment of mycoplasmas suspended in buffer increased with temperature, decreased with higher ionic strength, and showed a maximum at about pH 5.5. The findings suggest a participation of ionic bonds in the attachment process. Trypsin did not detach glass-bound mycoplasmas, and treatment of the cells with glutaraldehyde did not reduce their attachment to glass, suggesting that membrane components other than proteins may be involved in the attachment. Low concentrations (up to 20 mg/ml) of bovine serum albumin buffer. However, during the next few hours, attachment increased far above the bovine serum albumin control. This marked increase was reduced by more than half in the presence of chloramphenicol. Increased attachment was also observed when glucose (0.1 to 2 mg/ml) was added to the bovine serum albumin-containing buffer. The findings suggest different mechanisms for the attachment in protein-free buffer and in growth medium or glucose-containing bovine serum albumin buffer, respectively. The latter apparently requires metabolic activity of the mycoplasmas. 相似文献
5.
This study was undertaken to determine whether zinc, manganese and copper could regulate the thrombin-induced secretion of the granule-associated mediator, beta-hexosaminidase, from mast cells derived from mouse bone marrow. Exposure of thrombin to copper (2-100 microM) does not affect the enzyme-induced release of beta-hexosaminidase from the mast cells. Zinc at 50 microM reduced the degranulation of calcium ionophore A23187 activated cells by 75% and that of immunological challenge or thrombin by 30% each. Exposure of the thrombin to incremental concentrations of manganese (2-100 microM) prevents its degranulation activity in a dose-related fashion. 75% inhibition of the enzyme activity was achieved at 100 microM manganese. However, exposure of IgE sensitized or unsensitized cells to incremental concentrations of manganese (2-400 microM) prior to antigen or calcium ionophore A23187 stimulation, does not significantly affect the exocytosis of beta-hexosaminidase. The binding of purified human FITC-thrombin to E-mast cells was analyzed by fluorescence flow cytometry. All cells bound specifically the labelled thrombin. Pretreatment of the FITC-thrombin with 100 micron zinc or manganese had no effect on the binding of the labelled thrombin to the cells. It was assumed that manganese modulates either directly the thrombin activity or the substrate for the enzyme on the cell surface. 相似文献
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Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
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
8.
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
9.
Saroj Neupane M.D. Naga VA Kommuri M.D. Noora Kazanji D.O. Pertha Chowdhury M.D. F.A.C.C. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(11):1788-1789
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
10.