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This study evaluated the effect of three different NiTi instrumentation techniques on the incidence of microcracks after the preparation of straight and curved root canals using micro‐CT. Roots from mandibular premolars and maxillary molars (n = 66) with the same mean canal curvatures were assigned to three groups of straight and three groups of curved roots (n = 11). After preoperative micro‐CT scans, root canals were prepared with Reciproc, OneShape and ProTaper Next to size 25. Specimens were scanned again, and pre‐ and post‐operative cross‐sectional images (n = 75 263) were screened to identify the presence of dentinal microcracks. Overall, microcracks were detected in 2.97% (n = 2236) of the cross‐sectional images. No new dentinal microcracks were observed after root canal instrumentation of straight and curved canals with the tested NiTi systems. Instrumentation with Reciproc, OneShape and ProTaper Next did not induce the formation of dentinal microcracks irrespective of canal curvature.  相似文献   
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To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia.  相似文献   
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We tested whether there are age-related declines in detecting cues to trustworthiness, a skill that has been demonstrated to be rapid and automatic in younger adults. Young (Mage = 21.2 years) and older (Mage = 70.15 years) adults made criminal appearance judgments to unfamiliar faces, which were presented at a duration of 100, 500 or 1,000 ms. Participants’ response times and judgment confidence were recorded. Older were poorer than young adults at judging trustworthiness at 100 ms, and were slower overall in making their judgments. Further, the cues (i.e. perceptions of anger, trustworthiness and happiness) underlying criminality judgments were the same across age groups. Judgment confidence increased with increasing exposure duration for both age groups, while older adults were less confident in their judgments overall than their young counterparts. The implications are discussed.  相似文献   
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Previous single-case reports in posterior cortical atrophy (PCA) have shown preserved nonconscious visual recognition despite the absence of explicit recognition. In this study, we investigated three levels of visual recognition in both a female patient with PCA and a control group during the presentation of neutral, positive, and negative affective stimuli. Our results confirmed the profile of impaired explicit recognition and intact psychophysiological responses in the patient. In addition, she was able to implicitly recognize the valence and intensity of arousal of these stimuli. We suggest that implicit emotional awareness may mediates explicit and psychophysiological recognition in PCA.  相似文献   
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