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Journal of Neuro-Oncology - Craniopharyngioma is a benign tumor that commonly develops within the suprasellar region. The tumor and treatment can have debilitating consequences for pediatric and...  相似文献   
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The importance of an accurate diagnosis of the morphology of the root canal system is a prerequisite for successful root canal treatment and has been emphasized throughout the literature. Root canal morphology of premolar teeth, either maxillary or mandibular, and the discrepancies between first and second premolars, have been investigated and reported. A case report is presented of the root canal treatment of a mandibular second premolar with four root canals. As far as the reviewed literature revealed, up to three root canals in mandibular premolars have been reported. No previous report of a similar case of four root canals in a mandibular premolar was found.  相似文献   
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Current decision-making approaches in clinical medicine and dentistry are based on principles developed when diagnostic and therapeutic options were few. The rapid pace of new technology development and the role of third-party payment systems are increasingly requiring that health-care providers and patients confront very complex decisions. These decisions typically involve significant uncertainty (e.g., How will a specific patient respond to each possible treatment?) and difficult tradeoffs (e.g., How much are patients willing to pay in money, time, and treatment effectiveness to avoid pain and discomfort?). This paper discusses high-quality decision-making. High-quality diagnostic and therapeutic decisions result from a well-developed decision basis that represents the alternatives, information, and preferences pertaining to the decision at hand. An effective decision basis is framed to address patients' and clinicians' key concerns. The resulting recommendation for action is based on an understanding of what factors are most sensitive in determining the best course of action. Moreover, the value of additional information-gathering efforts (e.g., further diagnosis) can be measured before the information is obtained to determine whether it is worth more than it costs. The paper illustrates the need for better decision-making methods with a sample patient case, discusses key decision analysis principles and methods, identifies specific areas where periodontal decision-making can be improved by decision analysis, and presents a periodontal decision analysis case. It then discusses how intelligent decision system technology can make decision analysis widely available in a clinical setting and concludes by exploring how a future dental office might use this technology on a routine basis.  相似文献   
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Epithelial hyperplasia and metaplasia are common features of inflammatory and neoplastic disease, but the basis for the altered epithelial phenotype is often uncertain. Here we show that long-term ciliated cell hyperplasia coincides with mucous (goblet) cell metaplasia after respiratory viral clearance in mouse airways. This chronic switch in epithelial behavior exhibits genetic susceptibility and depends on persistent activation of EGFR signaling to PI3K that prevents apoptosis of ciliated cells and on IL-13 signaling that promotes transdifferentiation of ciliated to goblet cells. Thus, EGFR blockade (using an irreversible EGFR kinase inhibitor designated EKB-569) prevents virus-induced increases in ciliated and goblet cells whereas IL-13 blockade (using s-IL-13Ralpha2-Fc) exacerbates ciliated cell hyperplasia but still inhibits goblet cell metaplasia. The distinct effects of EGFR and IL-13 inhibitors after viral reprogramming suggest that these combined therapeutic strategies may also correct epithelial architecture in the setting of airway inflammatory disorders characterized by a similar pattern of chronic EGFR activation, IL-13 expression, and ciliated-to-goblet cell metaplasia.  相似文献   
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This study was designed to investigate the effects of altered pH on cellular aerobic energy metabolism in the immature and adult rat cerebral cortex. Cerebral cortical slice respiration was measured polarographically in acid and alkaline media. In separate experiments, the extracellular pH was changed by altering the HCO 3 concentration or the intracellular pH and extracellular pH were changed by altering the CO2. Respiratory rates and oxidative phosphorylation in adult rat cerebral mitochindria also were measured in media with an altered pH. Increased intracellular pH inhibited respiratory rates in cortical slices from immature rats more than in tissue from adults. Decreasing the pH to 6.7 produced no changes in respiration in mature cortical slices and moderate inhibition of immature tissue respiration. In cerebral mitochondria, altered pH caused inhibition of State 3 respiration, respiratory control ratios, and ADP/O ratios. These changes were greater and occurred with smaller pH changes in the alkaline compared to the acid direction. From the results of these studies, we conclude that brain cellular respiration is not affected by moderate decreases in intracellular pH. With increased pH, there is inhibition of cellular and mitochondrial respiration, which may be the mechanism for the rise in lactic acid previously observed to result from hypocarbiain vivo.Abbreviations used BSA bovine serum albumin - DNP dinitrophenol - RCR respiratory control ratio  相似文献   
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