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We conducted a retrospective study to evaluate the sensitivity, specificity and accuracy of positron emission tomography (PET) scans in 109 patients with primary recurrent or metastatic breast cancer. All patients had a PET scan, X-ray or CT scan of the chest, an ultrasound or CT scan of the liver and a bone scan. Mammography was available for 86 patients. Correlation between the PET scan result and histological findings were made. The sensitivity, specificity and accuracy of the PET scan were calculated for both the primary tumour (T) and lymph nodes (N). In patients with metastasis (M) the accuracy of the PET scan was compared with other imaging modalities. Histological results of the site in question were available in only 105 patients. Information for the primary tumour was available for 93 patients and for nodes in 74. The PET scan was accurate in 89.2% for (T), with 3.2% false positive and 7.6% false negative. For (N) the PET scan was accurate in 90.5% with 9.5% false negative. In the 86 patients who underwent both mammography and PET scanning, the PET scan was more accurate in 89.5% versus 72% (p = 0.0003). In the 19 patients with metastasis, the PET scan was in agreement with other imaging modalities in 100% of cases. PET scanning is the only non-invasive imaging procedure that will detect tumours in the breast, lymph nodes, lung, liver, bone and bone marrow with high sensitivity, specificity and accuracy. It is a valuable tool in the management of patients in all stages of breast cancer for diagnosis, staging and following treatment response.  相似文献   
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The oncogene c-maf is frequently overexpressed in multiple myeloma cell lines and patient samples and contributes to increased cellular proliferation in part by inducing cyclin D2 expression. To identify regulators of c-maf, we developed a chemical screen in NIH3T3 cells stably overexpressing c-maf and the cyclin D2 promoter driving luciferase. From a screen of 2400 off-patent drugs and chemicals, we identified glucocorticoids as c-maf-dependent inhibitors of cyclin D2 transactivation. In multiple myeloma cell lines, glucocorticoids reduced levels of c-maf protein without influencing corresponding mRNA levels. Subsequent studies demonstrated that glucocorticoids increased ubiquitination-dependent degradation of c-maf and up-regulated ubiquitin C mRNA. Moreover, ectopic expression of ubiquitin C recapitulated the effects of glucocorticoids, demonstrating regulation of c-maf protein through the abundance of the ubiquitin substrate. Thus, using a chemical biology approach, we identified a novel mechanism of action of glucocorticoids and a novel mechanism by which levels of c-maf protein are regulated by the abundance of the ubiquitin substrate.  相似文献   
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Objective

To assess the role of multi-detector CT (MDCT) in the pre and post operative evaluation of both potential donors and recipients for living related liver transplantation (LRLT).

Material and Methods

This prospective study included 26 patients for LRLT and their corresponding donors. For preoperative assessment, all subjects were evaluated by triphasic CT abdomen. CT angiography (CTA) with 3D reconstruction and CT volumetry was additionally done for donors. CT findings were compared to surgical results as gold standard reference. In post-operative evaluation, CT abdomen was performed at least once after transplantation for all recipients and for indicated donors. CTA was done for indicated recipients when US findings were inconclusive.

Results

No statistically significant difference was found between CT volumetry and intraoperative findings. Compared to surgical findings, MDCT identified hepatic arterial and portal venous anatomy with 100% sensitivity and specificity, while for hepatic venous anatomy; it showed sensitivity and specificity of 85.7% and 84.2%. Biliary complications and fluid collections were the commonest in recipients and donors respectively.

Conclusion

MDCT is a single comprehensive non-invasive and accurate imaging modality for preoperative evaluation of liver parenchyma, hepatic vascular anatomy and graft volume and postoperative complications in donors and recipients of LRLT.  相似文献   
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INTRODUCTIONSeveral congenital anomalies of the spleen have been reported. The polysplenia is a rare anomaly in which the normal spleen is replaced with two or more smaller spleens. The wandering spleen is another anomaly resulting from the laxity of the splenic ligaments. The concomitance of both anomalies is very rare.PRESENTATION OF A CASEA 22-year old female patient presented with intermittent left hypochondrial pain for more than a year. After a thorough examination of the patient, she only had bilateral accessory nipples. Routine laboratory investigations were all normal. An abdominal ultrasound U/S scan was unremarkable except for a ptotic spleen. with a large splenule 5 cm × 3 cm located near the fundus of the stomach. These findings were confirmed by a CT scan. A decision for a surgical intervention was then made, and the laparoscopic approach was chosen which revealed the condition. Laparoscopic removal of the wandering part was executed. The patient discharged on the first post-operative day.DISCUSSIONThe decision making in cases of wandering spleen is not always the same. The association of a wandering spleen with polysplenia is an asset to the surgical decision, along with the age of the patient.CONCLUSIONThe laparoscopic approach is an important tool in the diagnosis and management of wandering spleen. The diagnosis of polysplenic anomaly could provide a guidance for the surgical strategy in patients with wandering spleen.  相似文献   
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