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991.
Rescue excavations recovered a skeleton that resurrect the contemporary dramatic history of Austria in the 17th century as troops besieged Vienna in the second Osmanic-Habsburg war. Unique for Central Europe is the evidence of a completely preserved camel skeleton uncovered in a large refuse pit. The male individual of slender stature indicates a few but characteristic pathological changes revealing not a beast of burden but probably a valuable riding animal. Anatomical and morphometrical analyses suggest a hybrid confirmed by the ancient DNA analyses resulting in the presence of a dromedary in the maternal and a Bactrian camel in the paternal line.  相似文献   
992.

Background

Although exposure to second-hand smoke (SHS) has been associated with various medical conditions, only limited data are available on its association with health-related quality of life (HRQOL), particularly data obtained with the EQ-5D or EQ visual analogue scale (VAS).

Methods

This cross-sectional study evaluated 10,532 adult never-smokers who participated in the fifth Korea National Health and Nutrition Examination Survey. By using linear regression models to adjust for possible confounders and incorporating survey weights in analyses, the association between exposure to SHS and HRQOL—measured with the EQ-5D index and the EQ-VAS score—was evaluated. Data were further stratified by the amount of exposure time.

Results

After weighted analysis and adjustment, exposure to SHS was significantly associated with lower measures on the EQ-5D index (β = −0.007, P = 0.005) and EQ-VAS score (β = −1.936, P < 0.001). When comparing the unexposed group with the groups exposed <2h/day and ≥2h/day, exposure to a longer duration of SHS was significantly associated with lower scores on the EQ-5D index and the EQ-VAS score.

Conclusion

In conclusion, exposure to SHS was associated with reduced HRQOL measured by the EQ-5D index and EQ-VAS score, revealing a dose-response relationship.  相似文献   
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995.
Behavioral and cognitive improvements in children with ADHD have been consistently reported after neurofeedback-treatment. However, neurofeedback has not been commonly accepted as a treatment for ADHD. This study addresses previous methodological shortcomings while comparing a neurofeedback-training of Theta-Beta frequencies and training of slow cortical potentials (SCPs). The study aimed at answering (a) whether patients were able to demonstrate learning of cortical self-regulation, (b) if treatment leads to an improvement in cognition and behavior and (c) if the two experimental groups differ in cognitive and behavioral outcome variables. SCP participants were trained to produce positive and negative SCP-shifts while the Theta/Beta participants were trained to suppress Theta (4–8 Hz) while increasing Beta (12–20 Hz). Participants were blind to group assignment. Assessment included potentially confounding variables. Each group was comprised of 19 children with ADHD (aged 8–13 years). The treatment procedure consisted of three phases of 10 sessions each. Both groups were able to intentionally regulate cortical activity and improved in attention and IQ. Parents and teachers reported significant behavioral and cognitive improvements. Clinical effects for both groups remained stable six months after treatment. Groups did not differ in behavioural or cognitive outcome.  相似文献   
996.
Climate change is expected to result in more extreme weather conditions over large parts of Europe, such as the prolonged drought of 2003. As water supply is critical for tree growth on many sites in North-Western Europe, such droughts will affect growth, species competition, and forest dynamics. To be able to assess the susceptibility of tree species to climate change, it is necessary to understand growth responses to climate, at a high temporal resolution. We therefore studied the intra-annual growth dynamics of three beech trees (Fagus sylvatica L.) and five oak trees (Quercus robur L.) growing on a sandy site in the east of the Netherlands for 2 years: 2003 (oak and beech) and 2004 (oak). Microcores were taken at 2-week intervals from the end of April until the end of October. Intra-annual tree-ring formation was compared with prior and contemporary records of precipitation and temperature from a nearby weather station.The results indicate that oak and beech reacted differently to the summer drought in 2003. During the drought, wood formation in both species ceased, but in beech, it recovered after the drought. The causes of species-specific differences in intra-annual wood formation are discussed in the context of susceptibility to drought.  相似文献   
997.
The proteasome-dependent protein degradation participates in multiple essential cellular processes. Modulation of proteasomal activities may alter cardiac function and disease phenotypes. However, cardiovascular studies reported thus far have yielded conflicting results. We hypothesized that a contributing factor to the contradicting literature may be caused by existing proteasome heterogeneity in the myocardium. In this investigation, we provide the very first direct demonstration of distinct proteasome subpopulations in murine hearts. The cardiac proteasome subpopulations differ in their molecular compositions and proteolytic activities. Furthermore they were distinguished from proteasome subpopulations identified in murine livers. The study was facilitated by the development of novel protocols for in-solution isoelectric focusing of multiprotein complexes in a laminar flow that support an average resolution of 0.04 pH units. Utilizing these protocols, the majority of cardiac proteasome complexes displayed an isoelectric point of 5.26 with additional subpopulations focusing in the range from pH 5.10 to 5.33. In contrast, the majority of hepatic 20 S proteasomes had a pI of 5.05 and focused from pH 5.01 to 5.29. Importantly proteasome subpopulations degraded specific model peptides with different turnover rates. Among cardiac subpopulations, proteasomes with an approximate pI of 5.21 showed 40% higher trypsin-like activity than those with pI 5.28. Distinct proteasome assembly may be a contributing factor to variations in proteolytic activities because proteasomes with pI 5.21 contained 58% less of the inducible subunit beta 2i compared with those with pI 5.28. In addition, dephosphorylation of 20 S proteasomes demonstrated that besides molecular composition posttranslational modifications largely contribute to their pI values. These data suggest the possibility of mixed 20 S proteasome assembly, a departure from the currently hypothesized two subpopulations: constitutive and immuno forms. The identification of multiple distinct proteasome subpopulations in heart provides key mechanistic insights for achieving selective and targeted regulation of this essential protein degradation machinery. Thus, proteasome subpopulations may serve as novel therapeutic targets in the myocardium.  相似文献   
998.
We describe a statistical analysis methodology designed to minimize the impact of off-target activities upon large-scale RNA interference (RNAi) screens in mammalian cells. Application of this approach enhances reconfirmation rates and facilitates the experimental validation of new gene activities through the probability-based identification of multiple distinct and active small interfering RNAs (siRNAs) targeting the same gene. We further extend this approach to establish that the optimal redundancy for efficacious RNAi collections is between 4-6 siRNAs per gene.  相似文献   
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1000.
Abstract All known pilin sequences in Pseudomonas aeruginosa were amplified by a set of consensus primers located in the 5"-conserved region of pilA and the threonine-specific t-RNA following pilA . This also enabled the discovery of a novel pilin gene in a strain pair of clonal variants, which differs from known pilin genes in its increased GC-content. The mature protein has 173 amino acids making it the longest pilin known to date in P. aeruginosa . Different inserted sequences detected between the 3"-end of the pilin gene and the t-RNA in this strain and in strains with group I pilin genes seemed to be specific for each pilin group indicating a horizontal cotransfer of sequences.  相似文献   
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