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51.
Performance in a semantic task is speeded up for repeated stimuli compared to novel stimuli. This conceptual priming effect is related to a decrease in functional activation within the left inferior prefrontal cortex for repeated stimulus exposure (repetition suppression). However, in contrast to perceptual priming which is known to be very robust over long periods of time, previous studies on semantic priming focused on short-term effects. The present study combined a behavioral and functional imaging experiment to investigate long-term conceptual repetition priming (retention interval 3 days). We found a highly significant decrease of reaction time for word stimuli which were presented repeatedly after 3 days both compared to initial presentation and to a matched word list. The functional magnetic resonance imaging data showed a repetition suppression within the left inferior (BA45, BA47) and middle (BA9) frontal gyrus for the comparison of known with unknown words. These data demonstrate that even over a period as long as 3 days, a repetition suppression within the left frontal network involved in semantic decision can be found. Thus, priming-related mechanisms in the semantic network may be robust over several days.  相似文献   
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BACKGROUND Electrosurgical smoke could be different by the device of cutting or the type of tissue that is being cut.AIM To analyze the electrocautery smoke released from the tissues that are frequently cut in orthopedic surgeries.METHODS The released smoke from electrocautery of five different tissue types(meniscus,ligament,adipose,muscle,and synovium) of five patients who underwent total knee arthroplasty were collected and analyzed for volatile organic compounds(VOCs) and 27 candidate polycyclic aromatic hydrocarbons(n = 25).Surgical smoke was produced with an electrocautery device for 4 min.RESULTS None of the 27 evaluated polycyclic aromatic hydrocarbons compounds were detectable in electrocautery smoke collected from the surgical cutting of the different tissues.The number and identity of detected VOCs were similar between the patients but not between tissue types.The number of detected VOCs was the highest in synovial tissue(n = 21) and the lowest in the meniscus and adipose tissue(n = 12).The number of toxic and/or carcinogenic VOCs were the most in the muscle and meniscus tissues(Toluene,Ethylbenzene,and Styrene).No toxic and/or carcinogenic VOCs were identified in the ligament and adipose tissue.CONCLUSION Meniscus and muscle tissue are associated with the highest number of toxic and/or carcinogenic VOCs.Therefore,we recommend that surgeons avoiding the electrocautery of these tissues.  相似文献   
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Cardiac allograft vasculopathy (CAV) is an increasingly important complication after cardiac transplant. We assessed the additive diagnostic benefit of quantitative plaque analysis in patients undergoing coronary computed tomography–angiography (CCTA). Consecutive patients undergoing CCTA for CAV surveillance were identified. Scans were visually interpreted for coronary stenosis. Semiautomated software was used to quantify noncalcified plaque (NCP), as well as its components. Optimal diagnostic cut‐offs for CAV, with coronary angiography as gold standard, were defined using receiver operating characteristic curves. In total, 36 scans were identified in 17 patients. CAV was present in 17 (46.0%) reference coronary angiograms, at a median of 1.9 years before CCTA. Median NCP (147 vs 58, P < .001), low‐density NCP (median 4.5 vs 0.9, P = .003), fibrous plaque (median 76.1 vs 31.1, P = .003), and fibrofatty plaque (median 63.6 vs 27.6, P < .001) volumes were higher in patients with CAV, whereas calcified plaque was not (median 0.0 vs 0.0, P = .510). Visual assessment of CCTA alone was 70.6% sensitive and 100% specific for CAV. The addition of total NCP volume increased sensitivity to 82.4% while maintaining 100% specificity. NCP volume is significantly higher in patients with CAV. The addition of quantitative analysis to visual interpretation improves the sensitivity for detecting CAV without reducing specificity.  相似文献   
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This article develops a predictive robust H static output feedback control approach for networked control systems where random network-induced delays in both forward and feedback communication channels are modeled as two mutually uncorrelated Markov chains. By making use of the system augmentation method, the closed-loop system is formulated as a singular Markovian jump system with two modes, wherein the transition probability matrices of the underlying Markov chains are considered to be partially accessible. Necessary and sufficient conditions for the stochastic admissibility and robust H performance of the closed-loop system are given under the assumption of partially known transition probability matrices. A linear matrix inequality condition is proposed to determine the two-mode-dependent static output feedback controller gains to compensate for the random network-induced delays efficiently and provide the desired control performance. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed approach.  相似文献   
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Because informed consent requires discussion of alternative treatments, proper consent for dialysis should incorporate discussion about other renal replacement options including kidney transplantation (KT). Accordingly, dialysis providers are required to indicate KT provision of information (KTPI) on CMS Form-2728; however, provider-reported KTPI does not necessarily imply adequate provision of information. Furthermore, the effect of KTPI on pursuit of KT remains unclear. We compared provider-reported KTPI (Form-2728) with patient-reported KTPI (in-person survey of whether a nephrologist or dialysis staff had discussed KT) in a prospective ancillary study of 388 hemodialysis initiates. KTPI was reported by both patient and provider for 56.2% of participants, by provider only for 27.8%, by patient only for 8.3%, and by neither for 7.7%. Among participants with provider-reported KTPI, older age was associated with lack of patient-reported KTPI. Linkage with the Scientific Registry for Transplant Recipients showed that 20.9% of participants were subsequently listed for KT. Patient-reported KTPI was independently associated with a 2.95-fold (95% confidence interval [95% CI], 1.54 to 5.66; P=0.001) higher likelihood of KT listing, whereas provider-reported KTPI was not associated with listing (hazard ratio, 1.18; 95% CI, 0.60 to 2.32; P=0.62). Our findings suggest that patient perception of KTPI is more important for KT listing than provider-reported KTPI. Patient-reported and provider-reported KTPI should be collected for quality assessment in dialysis centers because factors associated with discordance between these metrics might inform interventions to improve this process.  相似文献   
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Purpose: Antimicrobial activities of meropenem products on Klebsiella pneumoniae isolates were determined. Methods: 212 non-duplicated Klebsiella pneumoniae isolates were examined for in vitro meropenem susceptibility test by using the following disks, which were made from Meronem (AstraZeneca, UK), Exipenem (Exir, Iran) and Meroxan (DAANA, Iran) powders. MIC50 and MIC90 for meropenem antibiotics were determined.Results: Meronem had good activities against most isolates of Klebsiella pneumoniae, and only a few strains had a rather high MIC. Exipenem and Meroxan showed a similar activity with Meronem. Conclusion: Regarding the comparison of two internal generic meropenem products with the external Meronem product have shown that they are equivalents in terms of microbiological activity, as measured using the disk diffusion and MIC. In developing countries, we suggested preparing disks with antibiotic powders that can be an equivalent function in microbiological activity with standard disks. In addition, since it demonstrated significant antimicrobial activity against the Klebsiella pneumoniae. For use of Exipenem and Meroxan in vivo, it would be better to perform additional testing (activity against different species, stability etc.).  相似文献   
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