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This study examines a wide range of numerical representations (i.e., quantity, knowledge of multiplication facts, and use of parity information) in adult deaf signers. We introduce a modified version of the number bisection task, with sequential stimulus presentation, which allows for a systematic examination of mathematical skills in deaf individuals in different modalities (number signs in streaming video vs. Arabic digit displays). Reaction times and accuracy measures indicated that deaf signers make use of several representations simultaneously when bisecting number triplets, paralleling earlier findings in hearing individuals. Furthermore, some differences were obtained between the 2 display modalities, with effects being less prominent in the Arabic digit mode, suggesting that mathematical abilities in deaf signers should be assessed in their native sign language.  相似文献   
173.

Introduction

Sparse data are available about the effect of therapy methods on antibody levels in patients with liver failure. The aim of this study was to determine serum immunoglobulin concentrations in patients with chronic hepatic failure (CHF), acute- (ALF), or acute-on-chronic liver failure (ACLF) and to evaluate the impact of MARS treatment or liver transplantation (LT) on antibody levels.

Materials and methods

We followed ten patients with ALF, twelve with ACLF and 18 with CHF. Eight patients with ALF and seven with ACLF underwent MARS therapy, whereas the rest received LT. 13 healthy volunteers served as controls. Serum antibody concentrations were measured using ELISA-technique.

Results

Median serum levels of IgA, IgG and IgM were significantly increased in patients with CHF compared to ALF or controls (P < 0.02, P < 0.01, and P < 0.01). IgM and IgG concentrations were also significantly elevated in patients with CHF compared to ACLF (IgM, 3.7 vs. 1 g/L, P < 0.001; IgG, 8.7 vs. 3.1 g/L, P = 0.004). Immediately after LT a significant decrease of IgA (6.9 vs. 3.1 g/L, P = 0.004), IgG (8.7 vs. 5.1 g/L, P = 0.02) and IgM (3.7 vs. 1.8 g/L, P = 0.001) was detected in patients with CHF and antibody levels further decreased the days after LT reaching levels comparable to healthy individuals. MARS treatment had no apparent effect on the immunoglobulin profile in patients with ALF or ACLF.

Conclusion

We provide evidence that LT reverses hypergammaglobulinemia in patients suffering from CHF within one day, which could be explained to a reconstituted hepatic antibody clearance, whereas MARS treatment has no immediate effect on immunoglobulin levels.Key words: antibodies, immunoglobulins, liver failure, liver transplantation, artificial liver support system, molecular adsorbent recirculating system  相似文献   
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The utilisation of motor performance tests for talent identification in youth sports is discussed intensively in talent research. This article examines the reliability, differential stability and validity of the motor diagnostics conducted nationwide by the German football talent identification and development programme and provides reference values for a standardised interpretation of the diagnostics results. Highly selected players (the top 4% of their age groups, U12–U15) took part in the diagnostics at 17 measurement points between spring 2004 and spring 2012 (= 68,158). The heterogeneous test battery measured speed abilities and football-specific technical skills (sprint, agility, dribbling, ball control, shooting, juggling). For all measurement points, the overall score and the speed tests showed high internal consistency, high test–retest reliability and satisfying differential stability. The diagnostics demonstrated satisfying factorial-related validity with plausible and stable loadings on the two empirical factors “speed” and “technical skills”. The score, and the technical skills dribbling and juggling, differentiated the most among players of different performance levels and thus showed the highest criterion-related validity. Satisfactory psychometric properties for the diagnostics are an important prerequisite for a scientifically sound rating of players’ actual motor performance and for the future examination of the prognostic validity for success in adulthood.  相似文献   
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