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151.
Objective:The purpose of this study is to validate a multivariable predictive model previously developed to differentiate between renal cell carcinoma (RCC) and oncocytoma using CT parameters.Methods and materials:We included 100 renal lesions with final diagnosis of RCC or oncocytoma studied before surgery with 4-phase multidetector CT (MDCT). We evaluated the characteristics of the tumors and the enhancement patterns at baseline, arterial, nephrographic and excretory MDCT phases.Results:Histopathologically 15 tumors were oncocytomas and 85 RCCs. RCCs were significantly larger (median 4.4 cm vs 2.8 cm, p = 0.006). There were significant differences in nodule attenuation in the excretory phase compared to baseline (median: 31 vs 42, p = 0.015), with RCCs having lower values. Heterogeneous enhancement patterns were also more frequent in RCCs (85.9% vs 60%, p = 0.027).Multivariable analysis showed that the independent predictors of malignancy were the enhancement pattern, with oncocytomas being more homogeneous in the nephrographic phase [Odds Ratio (OR) 0.16 (95% CI 0.03 to 0.75, p = 0.02)], nodule enhancement in the excretory phase compared to baseline, with RCCs showing lower enhancement [OR 0.96 (95% CI 0.93 to 0.99, p = 0.005)], and a size > 4 cm, with RCCs being larger [OR 5.89 (95% CI 1.10 to 31.58), p = 0.038].Conclusion:The multivariable predictive model previously developed which combines different MDCT parameters, including lesion size > 4 cm, lesion enhancement in the excretory phase compared to baseline and enhancement heterogeneity, can be successfully applied to distinguish RCC from oncocytoma.Advances in knowledge:This study confirms that multiparametric assessment using MDCT (including parameters such as size, homogeneity and enhancement differences between the excretory and the baseline phases) can help distinguish between RCCs and oncocytomas. While it is true that this multiparametric predictive model may not always correctly classify renal tumors such as RCC or oncocytoma, it can be used to determine which patients would benefit from pre-surgical biopsy to confirm that the tumor is in fact an oncocytoma, and thereby avoid unnecessary surgical treatments.  相似文献   
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ObjectivesTo evaluate success rate of type I tympanoplasty in adults and to investigate the importance of selected prognostic factors on graft uptake.Material and methodsRetrospective medical chart review of 155 patients who underwent Type I Tympanoplasty, in our department, from January 2013 to December 2017. Graft uptake rate was evaluated and the effects of prognostic factors on surgical outcome such as sex, smoking and otological surgery history, status of the contralateral ear, size and location of the perforation, middle ear mucosa status, surgical approach and graft material. Preoperative and postoperative audiometric data were collected, and the functional success was determined.ResultsThe overall surgical anatomical success rate was 75%. Analysis of the selected variables, identified as independent prognostic factors of anatomical unsuccess (95% CI): smoking (OR = 3.29, p < .01), middle ear tympanosclerosis (OR = 2.96; p = .04). Perforations above 50% of the tympanic membrane area had a borderline effect on graft uptake (p = .05). There was a significative improvement in the average air conduction thresholds of 7.44 dB and an ABG closure rate at 10 dB and 20 dB was achieved in 47% and 84.5%, respectively. Patients who received temporalis fascia graft had similar hearing gain compared to patients who underwent cartilage tympanoplasty (7.7 vs. 7.3 dB, p = .79).ConclusionType I tympanoplasty is an effective and safe procedure with a high anatomical success rate in the treatment of mucosal COM. Poorer outcomes were found in patients with smoking habits, in those with tympanosclerosis of middle ear mucosa and in larger perforations. These prognostic factors should be considered in surgical planning and patients should be advised to quit smoking. Tympanoplasty with cartilage graft had a hearing outcome comparable to temporalis fascia graft and should be considered in high-risk patients.  相似文献   
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Processing of emotions has been an enduring topic of interest in neuroimaging research, but studies have mostly used facial emotional stimuli. The aim of this study was to determine neural networks involved in emotion processing using scenic emotional visual stimuli. One hundred and twenty photographs from the International Affective Picture System (IAPS), including ecological scenes of disgust, fear, happiness, and sadness, were presented to 40 healthy participants while they underwent functional magnetic imaging resonance (fMRI). Afterwards they evaluated the emotional content of the pictures in an offline task. The occipito-temporal cortex and the amygdala–hippocampal complex showed a non-specific emotion-related activation, which was more marked in response to negative emotions than to happiness. The temporo-parietal cortex and the ventral anterior cingulate gyrus showed deactivation, with the former being marked for all emotions except fear and the latter being most marked for disgust. The fusiform gyrus showed activation in response to disgust and deactivation in response to happiness or sadness. Brain regions involved in processing of scenic emotion therefore resemble those reported for facial expressions of emotion in that they respond to a range of different emotions, although there appears to be specificity in the intensity and direction of the response.  相似文献   
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ObjectiveThe aim of this review is to summarize the current knowledge about axillary recurrences after sentinel lymph node (SLN) biopsy for breast cancer.MethodsA Pubmed search for publications (in English or French) related to breast cancer, SLN and axillary recurrence was carried out from 1995 to 2006.ResultsUnder controlled conditions (notably after a learning curve concerning the multidisciplinary team), the SLN procedure proved to be a reliable method for evaluation of axillary nodal status in selected patients with early-stage invasive breast cancer. When the SLN is free of cancer cells, the rate of axillary recurrence varies from 0% to 2% with a follow-up ranging from 14 to 57 months. Recurrence after axillary lymph node dissection is similar. When isolated cancer cells or micrometastases invaded the SLN, the rate of axillary recurrence remains low, but a complete axillary lymph node dissection must be performed to reduce this rate significantly. The use of intraoperative miniaturized gamma cameras could contribute to the optimization of the SLN procedure and to reduce axillary recurrences.  相似文献   
160.
The development of microsurgery has been dependent on experimental animals. Microsurgery could be a very valuable technique to improve experimental models of liver diseases. Microdissection and microsutures are the two main microsurgical techniques that can be considered for classifying the experimental models developed for liver research in the rat. Partial portal vein ligation, extrahepatic cholestasis and hepatectomies are all models based on microdissection. On the other hand, in portacaval shunts, orthotopic liver transplantation and partial heterotopic liver transplantation, the microsuture techniques stand out. By reducing surgical complications, these microsurgical techniques allow for improving the resulting experimental models. If good experimental models for liver research are successfully developed, the results obtained from their study might be particularly useful in patients with liver disease. Therefore experimental liver microsurgery could be an invaluable way to translate laboratory data on liver research into new clinical diagnostic and therapeutic strategies.  相似文献   
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