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991.
992.
Selective attention is not a unitary construct, but is composed of several processes. Attention selection may be guided by low-level stimulus properties, by the emotional value of the stimulus, or more voluntarily by the goals and plans of the observer. Whether these three systems operate independently during attention selection or not remains a debated question. We report results from two studies investigating the extent to which these different attention mechanisms may interact with one another. Using a standard dot probe paradigm wherein effects of exogenous, emotional, and endogenous attention were orthogonally manipulated, we found attentional facilitation effects for each component, indicated by faster decision times for validly, as opposed to invalidly cued targets. Moreover, results confirmed that these three attentional effects added up in a linear fashion. Complementing ERP results allowed us to disentangle the respective contributions of the two reflexive, bottom-up attention processes (exogenous vs. emotional) by showing non-overlapping temporal loci for attentional effects related either to low-level physical properties or the emotional content of the stimulus. These findings suggest that multiple separate attention mechanisms can operate simultaneously to yield a rapid and efficient visual processing of various classes of potentially relevant stimuli.  相似文献   
993.
994.

Aims

The authors analyzed the outcome of patients with Isolated Skin Recurrence After Salvage Mastectomy (ISRASM) performed after conservative treatment for breast carcinoma, taking into account initial tumor characteristics, intramammary recurrence (first recurrence) characteristics, local skin recurrence (second recurrence) characteristics, and the type of treatment at each stage of the breast cancer continuum.

Methods

Forty-two patients who had ISRASM between 1976 and 2007 were included in this retrospective study. Twenty-six factors were studied in univariate and multivariate analyses.

Results

Mean Overall Survival (OS) was 70.3 (±4.1) months. The 5-year OS rate was 66.6%. 31% of patients did not present any recurrence, 52% had locoregional recurrence and 14% metastatic recurrence following ISRASM. Univariate analysis showed that 4 prognostic factors were significantly related to OS and/or Disease-Free Survival (DFS): (1) initial chemotherapy after primary breast cancer (P = 0.09 and 0.01 respectively), (2) presence of emboli at the site of intramammary recurrence (first recurrence) (P = 0.02 and 0.03), (3) interval between first and second surgery of less than 3 years (P = 0.09 and 0.0003), and (4) inflammatory skin involvement at ISRASM (P = 0.005 and 0.17). Multivariate analysis showed that presence of emboli at the site of intramammary recurrence was significantly related to OS and that an interval between first and second recurrence of less than 3 years was significantly related to DFS.

Conclusion

Our results show that ISRASM affects a group of breast cancer patients with predominantly local rather than metastatic disease. Prognostic factors depend on characteristics at initial breast cancer, first recurrence and second recurrence. Evidence-based guidelines are still required for ISRASM management.  相似文献   
995.
Laparoscopic adjustable gastric banding (LAGB) is the first bariatric procedure in Europe and is becoming more and more popular in North America. However, the failure rate at 5 years can reach 50%. Although there is still no consensus on revisional surgery, the trend seems to be in favor of conversion to gastric bypass (GBP) with encouraging results. The aim of this study was to assess the results, the risks of conversion into GBP after failure of gastric banding. From January 2003 to July 2010, 85 patients had a revisional GBP after failure of LAGB, performed by two experienced surgeons. Post-operative morbidity, functional results, and weight loss were analyzed. The conversion rate was 2.3%. The mean operative time was 166 min. The mean length of stay was 5.2 days. The early morbidity rate was 7% and the mortality rate was nil. The mean body mass index (BMI) at the time of LAGB was 47.2 kg/m2 with the lowest BMI reached at 35. The mean BMI at conversion into GBP was 42.9 and the final BMI after a mean follow-up of 22 months was 34.8. Of the patients, 57.7% had a final BMI inferior to 35 and 15.3% had a final BMI superior to 40 and these were super obese and older patients. Super-obesity and advanced age appear to be factors of failure of LAGB and revisional GBP. However, conversion into GBP currently remains the choice procedure in case of gastric banding failure with satisfactory results and acceptable morbidity.  相似文献   
996.
997.
Gait and balance disorders are frequent in demented older adults. Their management (i.e., diagnosis, assessment and treatment) is challenging in daily practice because of numerous evaluation tests available, difficulties to select the most adapted intervention, and the lack of knowledge of physicians and health professionals concerning adapted centers to refer their patients to those patients. Thus, a working group of experts was organized by the Gérontop?le of Pays de Loire, France, in December 2010 with the aim to provide clinical guidelines for the management of older adults aged 65 years and older with mild to moderate dementia with gait and balance disorders. These guidelines provide answers to the following questions: 1) Is there gait and/or balance disorders? 2) Which specific tests used? and 3) How to treat patients?  相似文献   
998.
999.

Objective  

The purpose of this study was to evaluate the ability of a whole liver volume (WLV) segmentation algorithm to measure fat fraction (FF).  相似文献   
1000.
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