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A continuous stream of syllables is segmented into discrete constituents based on the transitional probabilities (TPs) between adjacent syllables by means of statistical learning. However, we still do not know whether people attend to high TPs between frequently co‐occurring syllables and cluster them together as parts of the discrete constituents or attend to low TPs aligned with the edges between the constituents and extract them as whole units. Earlier studies on TP‐based segmentation also have not distinguished between the segmentation process (how people segment continuous speech) and the learning product (what is learnt by means of statistical learning mechanisms). In the current study, we explored the learning outcome separately from the learning process, focusing on three possible learning products: holistic constituents that are retrieved from memory during the recognition test, clusters of frequently co‐occurring syllables, or a set of statistical regularities which can be used to reconstruct legitimate candidates for discrete constituents during the recognition test. Our data suggest that people employ boundary‐finding mechanisms during online segmentation by attending to low inter‐syllabic TPs during familiarization and also identify potential candidates for discrete constituents based on their statistical congruency with rules extracted during the learning process. Memory representations of recurrent constituents embedded in the continuous speech stream during familiarization facilitate subsequent recognition of these discrete constituents.  相似文献   
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Infantile hemangioma (IH) is a benign vascular tumor that gradually involutes over several years. Rapidly involuting congenital hemangioma (RICH) is the relatively rare congenital vascular tumor that is fully grown at birth and does not undergo postnatal growth and involutes during the first year. However, after involution of both IH and RICH, some have severe sequelae, such as redundant skin or conspicuous scarring, requiring additional treatment. We present the case of a 6-year-old girl with a concave deformity due to subcutaneous atrophy, skin darkening, and altered skin texture of her left zygomatic region following involution of a hemangioma. We successfully treated this patient by transferring a dermal fat graft. This technique can be beneficial for atrophic sequelae after regression of a hemangioma and is easy to perform and cosmetically effective.  相似文献   
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Cacao bean husk extract (CBH) was examined for inhibitory effects on the caries-inducing properties of mutans streptococci in vitro and on caries development in specific pathogen-free Sprague-Dawley rats infected with mutans streptococci. CBH reduced the growth rate of almost all oral streptococci examined, which resulted in the reduction of acid production. Furthermore, insoluble glucan synthesis by the glucosyltransferases from Streptococcus mutans MT8148R and Streptococcus sobrinus 6715 was significantly inhibited by CBH. Hence, the sucrose-dependent cell adherence of mutans streptococci was also depressed by CBH. The administration of CBH in drinking water resulted in significant reductions of caries development and dental plaque accumulation in rats infected with either Strep. sobrinus 6715 or Strep. mutans MT8148R, and the minimum cariostatic concentration was 1.0 mg/ml. These results indicate that CBH possesses powerful anticariogenic potential.  相似文献   
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INTRODUCTION: Actinobacillus actinomycetemcomitans has been implicated in the etiology of aggressive periodontitis. In this study, we applied a novel nucleic acid amplification method, called loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity, efficiency and rapidity under isothermal conditions, allowing the rapid detection of A. actinomycetemcomitans. METHODS: We designed the primers for detecting A. actinomycetemcomitans and evaluated the specificity and sensitivity of the assay. RESULTS: The LAMP primers used in this study successfully amplified serotypes a-e of A. actinomycetemcomitans, while other oral bacteria were not amplified. By measuring the precipitation of magnesium pyrophosphate, we could quantify the chromosomal DNA of A. actinomycetemcomitans. The detection limits using the real-time turbidimetry analysis were 5.8 x 10(2)-5.8 x 10(7) copies of A. actinomycetemcomitans template DNA per reaction tube. In addition, the LAMP assay was used for the rapid detection of A. actinomycetemcomitans in clinical specimens from eight individuals. The results with the LAMP method were similar to those using conventional polymerase chain reaction. CONCLUSION: Our results suggest that the LAMP-based assay is very useful for the rapid detection of A. actinomycetemcomitans.  相似文献   
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It is well known that plant extracts inhibit some enzymatic activities. The present study examined the inhibitory effects of natural plant extracts against the collagenolytic activity of Porphyromonas gingivalis. The enzyme was isolated from a culture supernatant of P. gingivalis 381. The aqueous and 50% ethanolic extracts of Ginkgo biloba, Mosla chinensis, Salvia officinalis, Cinnamomum cassia, and a catechin extract of Camellia sinensis exhibited strong inhibitory effects on collagenolytic activity. The activities of these plant extracts were higher than that of tetracycline-HCl. They also inhibited the cytotoxicity of P. gingivalis crude enzyme against human gingival fibroblasts. C. sinensis catechin was the most effective agent in neutralizing the cytotoxicity of P. gingivalis. The aqueous and 50% ethanolic extracts of C. cassia had relatively strong anti-cytotoxic activity. Although the other samples strongly inhibited the collagenolytic activity of P. gingivalis, they were not effectively anti-cytotoxic. The present findings suggest that C. sinensis and C. cassia extracts are effective in reducing the pathogenicity of periodontopathic bacteria.  相似文献   
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European Journal of Orthopaedic Surgery & Traumatology - Some reports suggested that the status of the opposite-side hip affects clinical outcomes of unilateral total hip arthroplasty (THA) for...  相似文献   
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