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991.
Hepatocellular carcinoma(HCC) is the 3~(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity and metabolic syndrome or genotoxins. Projections based on Western lifestyle and its metabolic consequences anticipate a further increase in incidence, despite recent breakthroughs in the management of viral hepatitis. HCCs display high heterogeneity of molecular phenotypes, which challenges clinical management. However, emerging molecular classifications of HCCs have not yet formed a unified corpus translatable to the clinical practice. Thus, patient management is currently based upon tumor number, size, vascular invasion, performance status and functional liver reserve. Nonetheless, an impressive body of molecular evidence emerged within the last 20 years and is becoming increasingly available to medical practitioners and researchers in the form of repositories. Therefore, the aim this work is to review molecular data underlying HCC classifications and to organize this corpus into the major dimensions explaining HCC phenotypic diversity. Major efforts have been recently made worldwide toward a unifying "clinically-friendly" molecular landscape. As a result, a consensus emerges on three major dimensions explaining the HCC heterogeneity. In the first dimension, tumor cell proliferation and differentiation enabled allocation of HCCs to two major classes presenting profoundly different clinical aggressiveness. In the second dimension, HCC microenvironment and tumor immunity underlie recent therapeutic breakthroughs prolonging patients' survival. In the third dimension,metabolic reprogramming, with the recent emergence of subclass-specific metabolic profiles, may lead to adaptive and combined therapeutic approaches. Therefore, here we review recent molecular evidence, their impact on tumor histopathological features and clinical behavior and highlight the remaining challenges to translate our cognitive corpus into patient diagnosis and allocation to therapeutic options.  相似文献   
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Objective

To review the outcome of women presenting with borderline glandular smear on cervical cytology and to investigate correlation between cytology, colposcopy and histology and subsequent smear history.

Study design

A 5 year retrospective analysis of outcome in all women reported with borderline glandular changes on cytology between 2001 and 2005 at the John Radcliffe Hospital, Oxford, and Cheltenham General Hospital, Gloucestershire, was performed. Cytology, colposcopy, histology and follow-up cytology data at 6, 12 and 24 months after index smear were collated.

Results

Of 92 women with borderline glandular smears, 56 were referred for colposcopy. This accounts for 0.9% of the total referral (6293) to the colposcopy units. A significant rate of abnormal histology was noted, with CIN 1, 2, 3, CGIN or worse in 20 women (36%) and benign pathology in 18 women (32%). Colposcopy had a sensitivity of 82%, specificity of 39%, negative predictive value of 80% and positive predictive value of 49% in predicting abnormal (premalignant/malignant) histology. Only one woman with normal histology at presentation had subsequent abnormal cytology (1/31), whereas abnormal histology at presentation was strongly associated with subsequent abnormality on follow-up cytology over 24 months (8/21) with a p value = 0.0058.

Conclusion

Colposcopic examination and biopsy of colposcopically identified abnormalities is reliable, with negative colposcopy having a high negative predictive value. We also recommend thorough colposcopic examination before any invasive investigation as over treatment may impact on the future reproductive outcome [1].  相似文献   
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Introduction

? Surgical and interventional procedures increasingly rely on spatial measurement systems. One of the most popular is NDI’s Polaris Vicra®. Unfortunately, this system cannot be used for magnetic resonance imaging (MRI) procedures because of the image artifacts that it produces.

Materials and methods

? Here, a simple method for hardware electrical shielding is presented which makes the Polaris Vicra® MR-compatible for a low-field open-magnet MR scanner. The shielding is achieved by placing the cable linking the sensor to the USB converter inside a copper braid tube.

Results

? Tests performed with a variety of MR sequences show the absence of image artifacts, image distortion or grey-level uniformity degradation. In the same way, 3D localization accuracy of the spatial measurement system is not modified by the MR environment. A rough safety check shows that the system does not pose hazards with normal condition of use.

Conclusion

? This minor adaptation makes the system suitable for various applications in low field MR environments, such as intraoperative and interventional MRI.  相似文献   
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PURPOSE: To report the normal sonographic anatomy of the triangular fibrocartilage (TFC) of the wrist in cadavers and volunteers. METHOD: Five hands from cadavers were examined sonographically before and after wrist dissection, during which the TFC was marked with surgical wires. Twenty volunteers without wrist limitation or pain, and without any history of wrist disease or inflammatory arthritis (mean age, 26 years (range,19-45 years) were also examined. RESULTS: Sonograms showed that the meniscus and the TFC were clearly separated. The meniscus appeared as a triangular structure that was homogeneous and slightly hyperechoic. Compared with the meniscus, the TFC appeared hypoechoic. The same patterns were observed for cadavers and volunteers. In 3 volunteers (15%), the TFC was not visualized. CONCLUSIONS: Using high-resolution ultrasound systems, the TFC can be separated from meniscus. However, visualization of the TFC remains limited due to its deep location and the presence of acoustic shadowing from bony structures.  相似文献   
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We investigated the effect of electrical stimulation of the medial pulvinar (PuM) in terms of its effect on temporal lobe seizures. Eight patients with drug‐resistant temporal lobe epilepsy undergoing stereoelectroencephalographic exploration were included. All had at least one electrode exploring the PuM. High‐frequency (50 Hz) stimulations of the PuM were well tolerated in the majority of them. During diagnostic stimulation to confirm the epileptogenic zone, 19 seizures were triggered by stimulating the hippocampus. During some of these seizures, ipsilateral pulvinar stimulation was applied (130 Hz, pulse width = 450 microseconds, duration = 3‐7 seconds, 1‐2 mA). Compared to non–PuM‐stimulated seizures, five of eight patients experienced clinically less severe seizures, particularly in terms of degree of alteration of consciousness. On the electrical level, seizures were more rapidly clonic with a shorter tonic phase. This proof of concept study is the first to suggest that PuM stimulation could be a well‐tolerated and effective means of therapeutic deep brain stimulation in drug‐resistant epilepsies.  相似文献   
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