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91.
Background : Previous research suggests that ADHD patients are characterized by both reduced activity in the inferior frontal gyrus (IFG) during response inhibition tasks (such as the Go‐NoGo task), and reduced activity in the ventral striatum during reward anticipation tasks (such as the Monetary‐Incentive‐Delay [MID] task). However, no prior research has applied either of these paradigms in medication‐naïve adults with ADHD, nor have these been implemented in an intrasubject manner. Methods : The sample consisted of 19 medication‐naïve adults with ADHD and 19 control subjects. Main group analyses were based on individually defined regions of interest: the IFG and the VStr for the Go‐NoGo and the MID task respectively. In addition, we analyzed the correlation between the two measures, as well as between these measures and the clinical symptoms of ADHD. Results : We observed reduced bilateral VStr activity in adults with ADHD during reward anticipation. No differences were detected in IFG activation on the Go‐NoGo paradigm. Correlation analyses suggest that the two tasks are independent at a neural level, but are related behaviorally in terms of the variability of the performance reaction time. Activity in the bilateral VStr but not in the IFG was associated negatively with symptoms of hyperactivity/impulsivity. Conclusions : Results underline the implication of the reward system in ADHD adult pathophysiology and suggest that frontal abnormalities during response inhibition performance may not be such a pivotal aspect of the phenotype in adulthood. In addition, our findings point toward response variability as a core feature of the disorder. Hum Brain Mapp 33:2350–2361, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
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The role of Ann Arbor staging in determining treatment intensity after achieving a negative positron emission tomography (PET) has not been established in classical Hodgkin lymphoma (cHL). Patients with stage I–IV cHL, received three cycles of ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) and an interim PET scan (PET3). PET3-negative patients received no further therapy. PET3-positive patients received three additional cycles of ABVD plus involved-field radiation therapy or salvage chemotherapy, if refractory to ABVD, and were re-evaluated by PET scan (PET6). Study endpoints were 3-year progression-free survival (PFS) and overall survival (OS) rates. Two hundred and thirty-nine patients with early-stage and 138 with advanced-stage were evaluable. Overall, 260 patients (70%) were PET3-negative and had higher 3-year PFS (90% vs. 65%; < 0·0001) and OS (98% vs. 92%; = 0·007) rates than PET3-positive patients. All PET3-negative patients, regardless of disease stage at diagnosis, achieved similarly good PFS (90–91%; = 0·76) and OS (97–99%). The only independent prognostic factor for PFS was PET3-negativity (Hazard ratio 3·8; 95% confidence interval 2·4–6·3; P < 0·0001). This study suggests that cHL patients who achieve a negative PET3 following ABVD have an excellent outcome, regardless of stage at diagnosis. An appropriately powered, phase III trial will be necessary to confirm these findings.  相似文献   
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International Urology and Nephrology - There have been conflicting data on the relative frequency of common forms of primary nephrotic syndrome (PNS). We undertook this study to look at the causes...  相似文献   
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Background  

It is estimated that 5–10% of all breast cancer are hereditary and attributable to mutations in the highly penetrance susceptibility genes BRCA1 and BRCA2. The genetic analysis of these genes is complex and expensive essentially because their length. Nevertheless, the presence of recurrent and founder mutations allows a pre-screening for the identification of the most frequent mutations found in each geographical region. In Spain, five mutations in BRCA1 and other five in BRCA2 account for approximately 50% of the mutations detected in Spanish families.  相似文献   
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Obstructive sleep apnea syndrome (OSAS) is a highly prevalent sleep disorder, characterized by repeated disruptions of breathing during sleep. This disease has many potential consequences including excessive daytime sleepiness, neurocognitive deterioration, endocrinologic and metabolic effects, and decreased quality of life. Metabolic syndrome is another highly prevalence emerging public health problem that represents a constellation of cardiovascular risk factors. Each single component of the cluster increases the cardiovascular risk, but the combination of factors is much more significant. It has been suggested that the presence of OSAS may increase the risk of developing some metabolic syndrome features. Moreover, OSAS patients are at an increased risk for vascular events, which represent the greatest morbidity and mortality of all associated complications. Although the etiology of OSAS is uncertain, intense local and systemic inflammation is present. A variety of phenomena are implicated in this disease such as modifications in the autonomic nervous system, hypoxemia-reoxygenation cycles, inflammation, and coagulation-fibrinolysis imbalance. OSAS patients also present increased levels of certain biomarkers linked to endocrine-metabolic and cardiovascular alterations among other systemic consequences. All of this indicates that, more than a local abnormality, OSAS should be considered a systemic disease.  相似文献   
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An enrichment culture technique was used to isolate soil bacteria capable of growing in the presence of two different concentrations of linear alkylbenzene sulfonates (LAS) (10 and 500 microg ml(-1)). Nine bacterial strains, representatives of the major colony types of aerobic heterotrophic cultivable bacteria in the enriched samples, were isolated and subsequently identified by PCR-amplification and partial sequencing of the 16S rRNA gene. Amongst the isolates, strains LAS05 (Pseudomonas syringae), LAS06 (Staphylococcus epidermidis), LAS07 (Delftia tsuruhatensis), LAS08 (Staphylococcus epidermidis) and LAS09 (Enterobacter aerogenes), were able to grow in pure culture in dialysed soil media amended with LAS (50 microg ml(-1)). The three Gram-negative strains grew to higher cell numbers in the presence of 50 microg ml(-1) of LAS, compared to LAS-unamended dialysed soil medium, and were selected for further testing of their ability to use LAS as carbon source. However, HPLC analysis of culture supernatants showed that the three strains can tolerate but not degrade LAS when grown in pure cultures. A higher concentration of soluble phosphates was recorded in dialysed soil media amended with LAS (50 microg ml(-1)) compared to unamended control media, suggesting an effect of the surfactant that enhanced the bioavailability of P from soil. The presence of LAS at a concentration of 50 microg ml(-1) had an important impact on growth of selected aerobic heterotrophic soil bacteria, a deleterious effect which may be relevant for the normal function and evolution of agricultural soil.  相似文献   
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