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51.
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Vertebral hemangiomas are common entities that rarely present with neurological deficits. The authors report the unusual case of a large L-3 vertebral hemangioma with epidural extension in a 27-year-old woman who presented with hip flexor and quadriceps weakness, foot drop, and leg pain. The characteristics of the mass on magnetic resonance imaging suggested an aggressive, hypervascular lesion. The patient underwent embolization of the lesion followed by direct intralesional injection of ethanol. Significant resolution of clinical symptoms was observed immediately after the procedure and at her follow-up visits. Follow-up imaging studies obtained 9 months after the procedure also documented a considerable reduction in the size of the hemangioma with minimal loss of vertebral height and a mild kyphosis at the affected level. On repeated imaging studies obtained 21 months postoperatively, the size of the hemangioma and the degree of vertebral body compression were stable. As demonstrated in this case, patients with vertebral hemangiomas can present with acute nerve root compression and signs and symptoms similar to those of disc herniation. Vertebral hemangiomas can be treated effectively with interventional techniques such as embolization and ethanol injection.  相似文献   
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Tamoxifen is the primary hormonal therapy for breast cancer as well as its chemoprevention. It is used in the management of breast cancer because of its anti oestrogenic effect. It is however an agonist on the endometrium with undesirable effects of endometrial proliferation with the risk of endometrial hyperplasia and carcinoma. Several authors have reported cases of endometrial hyperplasia and carcinoma following tamoxifen therapy for breast carcinoma. No such report has been made from Nigeria .This paper presents the first case of endometrial carcinoma following tamoxifen therapy for breast carcinoma in a 52 year old Nigerian female. It also highlights the recommended guidelines for the follow up of women with breast cancer on tamoxifen therapy.  相似文献   
54.

Background

Closure of atrial septal defect (ASD) among adults under transthoracic echocardiography (TTE) guidance using devices other than the Amplatzer Septal Occluder has not been extensively tested.

Aim of work

Assessment of the safety and efficiency of secundum ASD closure using the Occlutech Figulla ASD Occluder under TTE guidance in adult patients with hemodynamically significant secundum ASD.

Methods

Twenty patients (mean age, 32.9 ± 9.7, 75% of them females) were enrolled in the study. All patients underwent TTE and transoesophageal echocardiography (TEE) to assess the characteristics of the ASD prior to percutaneous closure. Procedures were performed using the Figulla Occluder device under both fluoroscopic and TTE guidance. Follow-up clinical and TTE examinations were done at 1, 3, and 6 months following the procedure.

Results

TTE estimated mean ASD size was 21.7 ± 7.3 mm with adequate rims except for the aortic rim (deficient in one third of cases). Mean device size was 28.1 ± 8.6 mm with mean procedure and fluoroscopic times of 46.2 ± 16.4 and 15.7 ± 5.4 minutes respectively. ASD was successfully closed in all patients. Two patients showed a small residual shunt immediately after the device placement that disappeared by the end of the 2nd followup TTE examination. Transient complications were detected in 2 patients. All patients were asymptomatic during the follow-up period.

Conclusion

Transcatheter closure of secundum ASD in adults under TTE guidance using the Occlutech Figulla ASD occluder device is safe and effective when performed in a tertiary center and by expert echocardiographers and interventional cardiologists.  相似文献   
55.
CD150 (signaling lymphocyte activation molecule [SLAM]) is a self-ligand cell surface glycoprotein expressed on T cells, B cells, macrophages, and dendritic cells. To further explore the role of CD150 signaling in costimulation and T(H)1 priming we have generated a panel of rat antimouse CD150 monoclonal antibodies. CD150 cell surface expression is up-regulated with rapid kinetics in activated T cells and lipopolysaccharide/interferon gamma (IFN-gamma)-activated macrophages. Anti-CD150 triggering induces strong costimulation of T cells triggered through CD3. DNA synthesis of murine T cells induced by anti-CD150 is not dependent on SLAM-associated protein (SAP, SH2D1A), because anti-CD150 induces similar levels of DNA synthesis in SAP(-/-) T cells. Antibodies to CD150 also enhance IFN-gamma production both in wild-type and SAP(-/-) T cells during primary stimulation. The level of IFN-gamma production is higher in SAP(-/-) T cells than in wild-type T cells. Anti-CD150 antibodies also synergize with interleukin 12 (IL-12) treatment in up-regulation of IL-12 receptor beta(2) mRNA during T(H)1 priming, and inhibit primary T(H)2 polarization in an IFN-gamma-dependent fashion. Cross-linking CD150 on CD4 T cells induces rapid serine phosphorylation of Akt/PKB. We speculate that this is an important pathway contributing to CD150-mediated T-cell proliferation.  相似文献   
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In situ X-ray crystallography powder diffraction studies on beta silicon carbide (3C-SiC) in the temperature range 25–800 °C at the maximum peak (111) are reported. At 25 °C, it was found that the lattice parameter is 4.596 Å, and coefficient thermal expansion (CTE) is 2.4 ×106/°C. The coefficient of thermal expansion along a-direction was established to follow a second order polynomial relationship with temperature (α11=1.423×1012T2+4.973×109T+2.269×106). CASTEP codes were utilized to calculate the phonon frequency of 3C-SiC at various pressures using density function theory. Using the Gruneisen formalism, the computational coefficient of thermal expansion was found to be 2.2 ×106/°C. The novelty of this work lies in the adoption of two-step thermal expansion determination for 3C-SiC using both experimental and computational techniques.  相似文献   
60.
In this review, we have discussed recent developments on the direct selenosulfonylation of unsaturated compounds which lead to the formation of two new carbon-sulfur and carbon-selenium bonds in a single operation. The reactions were classified based on the type of starting unsaturated compound and product. Thus, the review is divided into three major sections. The first describes the current literature on selenosulfonylation of alkenes. The second section covers the available literature on selenosulfonylation of alkynes. The third focuses exclusively on selenosulfonylation of allenes.

In this review, we have discussed recent developments on the direct selenosulfonylation of unsaturated compounds which lead to the formation of two new carbon-sulfur and carbon-selenium bonds in a single operation.  相似文献   
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