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991.
Sickle cell disease (SCD) does not occur in the indigenous German population. However, with the increasing numbers of immigrants its prevalence is steadily rising. Nevertheless, robust epidemiological data is not available for Germany and, consequently, the German newborn screening (NBS) program does not include SCD. Between 1 September 2011 and 30 November 2012, an unselected cohort of 34 084 Berlin newborns was tested for SCD. The results of 14 newborns were consistent with SCD and 265 babies were identified as hemoglobin S (Hb S) carriers. These data indicate a 95% probability that the incidence of SCD in Berlin is at least 2.5/10 000.  相似文献   
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Thermoresponsive polymer gels exhibit pronounced swelling and deswelling upon changes in temperature, making them attractive for applications in sensing and actuation. This volume phase transition can be discussed in terms of mean‐field theoretical pictures to assess at which conditions it occurs continuously or discontinuously. However, this treatment disregards static nano‐ and micrometer‐scale inhomogeneities in gel polymer networks, which are a common feature of these materials. To check for the impact of such structural complexity, droplet‐based microfluidics are used to fabricate sub‐millimeter‐sized gel particles that exhibit critical compositions at the border between continuous to discontinuous volume phase transitions, along with determined static spatial polymer‐network heterogeneity on the nano­meter and micrometer length scales, which is characterized by low‐field NMR. These different microgels are then used to study their swelling and deswelling volume phase transitions from a sub‐millimeter perspective. In this investigation, microgel particles with similar content of crosslinker exhibit similar swelling and deswelling, independent of their extent of static polymer‐network inhomogeneity, in agreement with mean‐field theoretical predictions.

  相似文献   

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Background

Although positron emission tomography (PET) imaging is widely recommended in the evaluation of patients with lung cancer, randomized controlled trials (RCTs) assessing this have demonstrated inconsistent results. We asked whether differences in the clinical context and endpoints could explain these discrepancies.

Methods

We used realist synthesis methods to analyze how contextual differences among RCTs affected the results. We focused on RCTs to minimize confounding yet permit evaluation of differences by comparing across studies.

Results

This analysis suggests that the impact of PET depends on the clinical setting. PET is of greatest benefit in identifying M1 disease in patients with a high chance of such involvement and when little traditional imaging [e.g., abdominal/pelvis computed tomography (CT) and bone scan] is used. Identification of N2,3 involvement by PET prior to resection is seen primarily when there is at least a moderate probability of such and the rate of invasive staging is high. The rate of N2 disease not identified preoperatively appears to increase if PET is used to avoid invasive mediastinal staging in clinical settings in which the risk of N2,3 involvement is moderately high. There is both a potential benefit in avoiding stage-inappropriate resection as well as a risk of missed (stage-appropriate) resection if PET findings are not evaluated carefully.

Conclusions

A blanket recommendation for PET may be too simplistic without considering nuances of the clinical setting.  相似文献   
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Aims/hypothesis

Oxidative stress plays a key role in the development of type 2 diabetes mellitus. We previously showed that the circulating antioxidant peroxiredoxin 4 (Prx4) is associated with cardiometabolic risk factors. We aimed to evaluate the association of Prx4 with type 2 diabetes risk in the general population.

Methods

We analysed data on 7,972 individuals from the Prevention of Renal and Vascular End-stage Disease (PREVEND) study (49% men, aged 28–75 years) with no diabetes at baseline. Logistic regression models adjusted for age, sex, smoking, waist circumference, hypertension and family history of diabetes were used to estimate the ORs for type 2 diabetes.

Results

During a median follow up of 7.7 years, 496 individuals (288 men; 58%) developed type 2 diabetes. The median (Q1–Q3) Prx4 level was 0.84 (0.53–1.40) U/l in individuals who developed type 2 diabetes and 0.68 (0.43–1.08) U/l in individuals who did not develop type 2 diabetes. For every doubling of Prx4 levels, the adjusted OR (95% CI) for type 2 diabetes was 1.16 (1.05–1.29) in the whole population; by sex, it was 1.31 (1.14–1.50) for men and 1.03 (0.87–1.21) for women. Further adjustment for other clinical measures did not materially change the results. The addition of Prx4 to a validated diabetes risk score significantly improved the prediction of type 2 diabetes in men (p?=?0.002 for reclassification improvement).

Conclusions/interpretation

Our findings suggest that elevated serum Prx4 levels are associated with a higher risk of incident type 2 diabetes. For men, taking Prx4 into consideration can improve type 2 diabetes prediction over a validated diabetes risk score; in contrast, there is no improvement in risk prediction for women.  相似文献   
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