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71.
72.
What role does personality play in the pervasive gender gap in entrepreneurship across the globe? This two-study analysis focuses on self-employment in the working population and underlying gender differences in personality characteristics, thereby considering both single trait dimensions as well as a holistic, configural personality approach. Applying the five-factor model of personality, Study 1, our main study, investigates mediation models in the prediction of self-employment status utilizing self-reported personality data from large-scaled longitudinal datasets collected in the U.S., Germany, the U.K., and Australia (total N = 28,762). Study 2 analyzes (observer-rated) Big Five data collected in 51 cultures (total N = 12,156) to take a more global perspective and to explore the pancultural universality of gender differences in entrepreneurial personality characteristics. Across the four countries investigated in Study 1, none of the major five dimension of personality turned out as a consistent and robust mediator. In contrast, the holistic, configural approach yielded consistent and robust mediation results. Across the four countries, males scored higher on an entrepreneurship-prone personality profile, which in turn predicted self-employment status. These results suggest that gender differences in the intra-individual configuration of personality traits contribute to the gender gap in entrepreneurship across the globe. With the restriction of limited representativeness, the data from Study 2 suggest that the gender difference in the entrepreneurship-prone personality profile (males score higher) is widespread across many cultures, but may not exist in all. The results are discussed with an emphasis on implications for research and practice, which a particular focus on the need for more complex models that incorporate the role of personality.  相似文献   
73.
Heterogeneous DNA methylation leads to difficulties in accurate detection and quantification of methylation. Methylation-sensitive high resolution melting (MS-HRM) is unique among regularly used methods for DNA methylation analysis in that heterogeneous methylation can be readily identified, although not quantified, by inspection of the melting curves. Bisulfite pyrosequencing has been used to estimate the level of heterogeneous methylation by quantifying methylation levels present at individual CpG dinucleotides. Sequentially combining the two methodologies using MS-HRM to screen the amplification products prior to bisulfite pyrosequencing would be advantageous. This would not only replace the quality control step using agarose gel analysis prior to the pyrosequencing step but would also provide important qualitative information in its own right. We chose to analyze DAPK1 as it is an important tumor suppressor gene frequently heterogeneously methylated in a number of malignancies, including chronic lymphocytic leukemia (CLL). A region of the DAPK1 promoter was analyzed in ten CLL samples by MS-HRM. By using a biotinylated primer, bisulfite pyrosequencing could be used to directly analyze the samples. MS-HRM revealed the presence of various extents of heterogeneous DAPK1 methylation in all CLL samples. Further analysis of the biotinylated MS-HRM products by bisulfite pyrosequencing provided quantitative information for each CpG dinucleotide analyzed, and confirmed the presence of heterogeneous DNA methylation. Whereas each method could be used individually, MS-HRM and bisulfite pyrosequencing provided complementary information for the assessment of heterogeneous methylation.Key words: MS-HRM, pyrosequencing, digital PCR, heterogeneous DNA methylation, DAPK1, chronic lymphocytic leukemia  相似文献   
74.
Taxonomic arrangement of Hypnum species has been controversial since the beginning of the nineteenth century. The molecular pattern and phylogenetic relationships within the Hypnum cupressiforme complex, in relation to other pleurocarps species, were investigated by study of nuclear ribosomal ITS1/ITS2 and chloroplast trnLUAA intron sequences. Seven Hypnum species from different continents were sequenced and analysed, with a relatively large set of pleurocarpous mosses. Sequences indicate a low level of genetic differentiation within the complex. Both maximum parsimony and maximum likelihood analyses indicate that Hypnum s.l. is distributed in several clades of pleurocarps; in addition, H. cupressiforme sensu strictu, and the complex, are not monophyletic. Our results clearly circumscribe only two species, H. jutlandicum and H. imponens; phylogenetic analyses, in particular, highlight the isolation of the latter from the complex. Genetic lineages with a clear geographic structure were found in Eurasia; these probably originated during the last glaciations. The presence of H. cupressiforme in some related clades flanking the other species examined supports the occurrence of an ongoing speciation within the complex.  相似文献   
75.
Brugada syndrome (BrS) is associated with ventricular tachycardia originating particularly in the right ventricle (RV). We explore electrophysiological features predisposing to such arrhythmic tendency and their possible RV localization in a heterozygotic Scn5a+/- murine model. Na(v)1.5 mRNA and protein expression were lower in Scn5a+/- than wild-type (WT), with a further reduction in the RV compared with the left ventricle (LV). RVs showed higher expression levels of K(v)4.2, K(v)4.3 and KChIP2 in both Scn5a+/- and WT. Action potential upstroke velocity and maximum Na(+) current (I(Na)) density were correspondingly decreased in Scn5a+/-, with a further reduction in the RV. The voltage dependence of inactivation was shifted to more negative values in Scn5a+/-. These findings are predictive of a localized depolarization abnormality leading to slowed conduction. Persistent Na(+) current (I(pNa)) density was decreased in a similar pattern to I(Na). RV transient outward current (I(to)) density was greater than LV in both WT and Scn5a+/-, and had larger time constants of inactivation. These findings were also consistent with the observation that AP durations were smallest in the RV of Scn5a+/-, fulfilling predictions of an increased heterogeneity of repolarization as an additional possible electrophysiological mechanism for arrhythmogenesis in BrS.  相似文献   
76.

Background

Delirium is a common disorder in the early phase of stroke. Given the presumed cholinergic deficiency in delirium, we tested treatment with the acetylcholinesterase inhibitor rivastigmine.

Methods

This pilot study was performed within an epidemiological study. In 527 consecutive stroke patients presence of delirium was assessed during the first week with the confusion assessment method. Severity was scored with the delirium rating scale (DRS). Sixty-two patients developed a delirium in the acute phase of stroke. Only patients with a severe and persistent delirium (defined as a DRS of 12 or more for more than 24 hours) were enrolled in the present study. In total 26 fulfilled these criteria of whom 17 were treated with orally administered rivastigmine with a total dose between 3 and 12 mg a day. Eight patients could not be treated because of dysphagia and one because of early discharge.

Results

No major side effects were recorded. In 16 patients there was a considerable decrease in severity of delirium. The mean DRS declined from 14.8 on day one to 8.5 after therapy and 5.6 after tapering. The mean duration of delirium was 6.7 days (range; 2–17).

Conclusion

Rivastigmine is safe in stroke patients with delirium even after rapid titration. In the majority of patients the delirium improved after treatment. A randomized controlled trial is needed to establish the usefulness of rivastigmine in delirium after stroke.

Trial registration

Nederlands Trial Register NTR1395
  相似文献   
77.

Background  

A close association between Sst I polymorphism in the 3' untranslated region of the apolipoproteinC3 (APOC3 ) gene and levels of plasma triglycerides (TG) had been reported by different investigators. Hypertriglyceridemia(HTG) is a known risk factor for coronary artery disease (CAD) in the context of Asian Indians. We conducted a study on the relationship between APOC3 SstI polymorphism (S1S1, S1S2 and S2S2 genotypes) and plasma TG levels in a group of 139 male healthy volunteers from Northern India.  相似文献   
78.
The natural cyclopeptide FR235222 is a potent HDAC inhibitor displaying relevant multiple anticancer effects and is considered an attractive lead compound for the generation of new and more effective antitumor therapeutics. Recently, we have synthesized a small collection of FR235222 simplified analogues which showed interesting biological activities. These results encouraged us to further explore the structural determinants responsible for the activity of this class of HDAC inhibitors in order to gain guidelines for the rational design of new derivatives with putative higher affinity for this target. In the present paper, we report the results obtained, docking these ligands in the binding pocket of HDLP, an HDAC homologue.  相似文献   
79.
One pot microwave-assisted synthesis of substituted 1,2,4-oxadiazoles in solvent and under solvent free condition was performed exploring the importance of some coupling reagents. Good yields and short reaction times were the main aspects of the methods.  相似文献   
80.
Kinases are an important therapeutic target for drug discovery, and many cancer chemotherapeutic agents have been derived from natural product sources. Natural product samples, however, have the likelihood of assay interference, particularly at elevated test concentrations. The authors developed a competitive fluorescence polarization (FP) assay using red-shifted fluorophores for the AKT kinase and demonstrated utility for testing concentrated natural product extracts. A set of 7 actinomycetes cultures containing indolocarbazoles, known nonselective kinase inhibitors, and a control set of 22 nonproducing indolocarbazole cultures were evaluated. Using red-shifted dyes (Cy3B or Cy5), the authors identified active samples with minimal interference up to the extract concentrations that are 3 times nonextracted culture levels. In contrast, a significant number of interferences were observed using either a fluorescein competitive FP assay or a [33P]ATP Flashplate assay. This work demonstrates that one can screen natural product extracts at high concentrations successfully using FP technology with red-shifted dyes.  相似文献   
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