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Desmoid tumors are currently the main cause of morbidity and mortality in patients with familial adenomatous polyposis. More than 10% of these patients will develop these tumors during their lifetime and more than a third will suffer their consequences. The main risk factors for their development are female sex and abdominal surgery. The most frequent localization is intraabdominal. The therapeutic approach to these tumors has changed, and the surgical treatment of choice is currently the subject of debate. If a watch and wait approach is adopted, more than 50% of tumors will prove to be indolent. Therefore, the therapeutic strategy should be based on clinical presentation and should be decided by a multidisciplinary team working in a center with experience of these tumors. The present article proposes a prognostic classification to guide the therapeutic approach.  相似文献   
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Cerebral white matter lesions (WMLs) are related to cognitive deficits, probably due to a disruption of frontal–subcortical circuits. We explored thalamic diffusion differences related to white matter lesions (WMLs) and their association with cognitive function in middle-aged individuals. Ninety-six participants from the Barcelona-AsIA Neuropsychology Study were included. Participants were classified into groups based on low grade and high grade of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs). Tract-Based Spatial Statistics was used to study thalamic diffusion differences between groups. Mean fractional anisotropy (FA) values in significant areas were calculated for each subject and correlated with cognitive performance. Participants with high-grade PVHs and DWMHs showed lower FA thalamic values compared to those with low-grade PVHs and DWMHs, respectively. Decreased FA thalamic values in high-grade DWMHs, but not high-grade PVH, were related to lower levels of performance in psychomotor speed, verbal fluency, and visuospatial skills. Thalamic diffusion differences are related to lower cognitive function only in participants with high-grade DWMHs. These results support the hypothesis that fronto–subcortical disruption is associated with cognitive function only in DWMHs.  相似文献   
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Anemia is very common entity or comorbidity in surgical patients. Its management involves a multidisciplinary approach with the aim of optimizing the available therapeutic resources with individualized care for each clinical situation. Rational use of blood transfusions, iron therapy (oral and intravenous), erythropoiesis stimulating agents and other therapeutic alternatives by physicians must achieve maximal benefit with minimal complications for our patients. This review article summarizes the main characteristics of anemia, iron metabolism, erythropoiesis and therapeutic alternatives from a surgical perspective in the light of present knowledge.  相似文献   
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Peribronchiolar metaplasia is a histologic lesion characterized by fibrosis and bronchiolar epithelial proliferation, affecting peribronchiolar alveolar septa and terminal bronchioles. It has been considered a nonspecific tissue reaction secondary to the action of external factors, such as tobacco smoke and microbes, and is a common histologic finding in several diffuse interstitial lung diseases. Several such cases with clinical, radiologic, and lung function manifestations characteristic of idiopathic interstitial pneumonia have been described recently, all having peribronchiolar metaplasia as the only histologic abnormality. We report 2 cases of interstitial lung disease in which peribronchiolar metaplasia was the only finding of pathology.  相似文献   
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Background: Patients with impaired left ventricular function have a high risk of developing ventricular arrhythmias and sudden death. Among different markers of risk, the prolongation and regional heterogeneity of repolarization are of increasing interest. However, there are limited data regarding feasibility of analyzing repolarization parameters and their dynamics in 24‐hour Holter ECG recordings. Methods: Dynamic behavior of repolarization parameters was studied with a new automatic algorithm in digital 24‐hour Holter recordings of 60 healthy subjects and 55 patients with idiopathic dilated cardiomyopathy (IDC). Repolarization parameters included the mean value of QT and QTc durations, QT dispersion, and peaks of QT duration and QT dispersion above prespecified thresholds. Results: In comparison to healthy subjects, patients with IDC had lower heart rate variability, longer mean QT and QTc durations, higher content of QTc peaks >500 ms, longer QT dispersion and its standard deviation, and a higher content of peaks >100 ms of QT dispersion (P < 0.01 for all comparisons). These repolarization parameters were significantly higher in IDC patients after adjustment for age, sex, and heart rate variability. The parameters of repolarization dynamics correlated with SDNN in healthy subjects but not in dilated cardiomyopathy patients. Conclusions: The automatic assessment of repolarization parameters in 24‐hour digital ECG recordings is feasible and differentiates dilated cardiomyopathy patients from healthy subjects. Patients with dilated cardiomyopathy have increased QT duration, QT dispersion, and increased variability of QT dispersion reflecting variations in T‐wave morphology, the factors which might predispose them to the development of arrhythmic events.  相似文献   
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Lim MC  Shipston MJ  Antoni FA 《Endocrinology》2002,143(10):3796-3801
Diagnostic tests of hypothalamic-pituitary-adrenocortical function in psychiatric illness largely report the interaction of hypothalamic secretagogues with glucocorticoids at the pituitary level. This study investigated whether the efficiency of glucocorticoid inhibition is subject to modulation by intracellular processes that enhance cAMP accumulation and/or facilitate membrane depolarization. The secretion of ACTH induced by corticotropin-releasing factor (CRF; 0.1 nM) in primary cultures of rat anterior pituitary cells was markedly inhibited upon a 2-h exposure to 100 nM corticosterone. Arginine vasopressin (2 nM) enhanced the cAMP as well as the ACTH responses to CRF and reduced the efficiency of glucocorticoid inhibition of ACTH release. The action of arginine vasopressin was mimicked by rolipram, an inhibitor of cyclic nucleotide phosphodiesterase type 4. Application of the broad specificity K(+) channel blockers clofilium and astemizole produced minor or no significant enhancement of CRF-induced ACTH release, respectively, but opposed the inhibitory effect of corticosterone. Specific blockers of HERG, KCNQ, and Isk channels had no effect on ACTH release under any condition examined. In summary, these data reveal multiple sites of posttranslational modulation of adrenal corticosteroid action at the level of the pituitary gland, which appear important for the outcome of diagnostic tests of hypothalamic-pituitary- adrenocortical function.  相似文献   
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