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Conflict monitoring and motor inhibition are engaged in the performance of complex tasks. The midcingulate cortex (MCC) has been suggested to detect conflicts, whereas the right inferior frontal cortex (IFC) seems to be of relevance for the inhibition process. The current experiment investigates the neural underpinnings of their interplay via a modified flanker paradigm. Conflict was manipulated by the congruency of flanking stimuli relative to a target (congruent vs. incongruent) and motor inhibition by a within‐trial response change of the initiated response (keep response vs. stop‐change). We used event‐related functional magnetic resonance imaging, decomposition with high model order ICA, and single trial analysis to derive a functional parcellation of the whole‐brain data. Results demonstrate the segmentation of the MCC into anterior and posterior subregions, and of the IFC into the pars opercularis, pars triangularis, and pars orbitalis. The pars opercularis and pars triangularis of the right IFC constituted the foundation of inhibition‐related networks. With high conflict on incongruent trials, activity in the posterior MCC network, as well as in one right IFC network was observed. Stop‐change trials modulated both the MCC as well as networks covering extended parts of the IFC. Whereas conflict processing and inhibition most often are studied separately, this study provides a synopsis of functionally coupled brain regions acting in concert to enable an optimal performance in situations involving interference and inhibition. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Unavoidable side reactions of photosynthetic energy conversion can damage the water-splitting photosystem II (PSII) holocomplex embedded in the thylakoid membrane system inside chloroplasts. Plant survival is crucially dependent on an efficient molecular repair of damaged PSII realized by a multistep repair cycle. The PSII repair cycle requires a brisk lateral protein traffic between stacked grana thylakoids and unstacked stroma lamellae that is challenged by the tight stacking and low protein mobility in grana. We demonstrated that high light stress induced two main structural changes that work synergistically to improve the accessibility between damaged PSII in grana and its repair machinery in stroma lamellae: lateral shrinkage of grana diameter and increased protein mobility in grana thylakoids. It follows that high light stress triggers an architectural switch of the thylakoid network that is advantageous for swift protein repair. Studies of the thylakoid kinase mutant stn8 and the double mutant stn7/8 demonstrate the central role of protein phosphorylation for the structural alterations. These findings are based on the elaboration of mathematical tools for analyzing confocal laser-scanning microscopic images to study changes in the sophisticated thylakoid architecture in intact protoplasts.  相似文献   
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Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie - Aim of the study was to compare how six different sealants resisted thermal, mechanical, and chemical loading in vitro....  相似文献   
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ObjectiveTo determine the rate and factors associated with publication of plenary abstract presentations from the Society of Gynecologic Oncologists annual meeting.MethodsPlenary presentations were reviewed from 2000 to 2005. A PubMed search was performed to identify subsequent peer-reviewed publication of these presentations. Chi-squared test and logistic regression were used for statistical analyses.ResultsOf 378 main, focused or express plenary presentations, 173 (45.8%) involved multiple and 205 (54.2%) single institutions. The types of study include: chart review (29.4%), cohort study (28.0%), translational (23.5%), and randomized clinical trial (6.9%). 309 (81.7%) of presentations were subsequently published. The median time from presentation to publication was 14 months (range: 1–85). Studies from multiple vs. single institutions were more likely to be published (87.9% vs. 76.6%; p = 0.005). In addition, randomized controlled trials were more likely to be published compared with chart review, cohort, and translation research (92.3% vs. 83.8%, 77.4%, and 74.2%; p < 0.01). On multivariate analysis, multi-institutional studies (OR = 2.28, 95% CI = 1.28–4.04; p = 0.005) and type of study (OR = 1.64, 95% CI = 1.19–2.26; p = 0.002) were independent factors associated with publication. In addition, multi-institutional studies had longer times from presentation to publication compared with their counterparts.ConclusionsA high percentage of plenary presentations at the Society of Gynecologic Oncologists annual meeting resulted in subsequent publication. Multi-institutional studies and randomized clinical trials were more likely to be published.  相似文献   
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Objective: In the absence of head-to-head trials, this study indirectly compared progression free survival (PFS) and overall survival (OS) between ceritinib and crizotinib among patients with previously untreated advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC).

Methods: A matching-adjusted indirect comparison method was implemented to adjust for cross-trial differences in patient characteristics between ASCEND-4 and PROFILE 1014 trials. Patient-level data from ASCEND-4 and published summary data from PROFILE 1014 were used. Patients in ASCEND-4 were reweighted to match average baseline characteristics (i.e. age, sex, race, tumor histology, ECOG score, smoking status, extent of disease, and presence of brain metastases) reported for PROFILE 1014 patients using propensity score weighting. PFS and OS were then compared between balanced populations.

Results: ASCEND-4 included more current smokers (8.0% vs 4.4%) and fewer patients under the age of 65 years (78.5% vs 84.0%) compared to PROFILE 1014. After matching, these and all other patient characteristics were balanced between the two trial populations. Compared to crizotinib, ceritinib was associated with a significantly longer PFS (hazard ratio [95% confidence interval] (HR [CI])?=?0.64 [0.47–0.87]; median PFS: 25.2 vs 10.8 months, log-rank p-value?=?0.003). OS did not differ significantly, with a HR of 0.82 [0.54–1.27] for ceritinib compared to crizotinib.

Conclusions: In the adjusted indirect comparison with external controls, the second generation ALK inhibitor, ceritinib, was associated with a significantly prolonged PFS compared to crizotinib as first-line treatment for ALK-positive NSCLC.  相似文献   

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