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1.
Clinical Autonomic Research - Comparison of hemodynamic profiles and pain scores in diabetic patients undergoing diabetic foot surgery receiving peripheral nerve block (PNB) or spinal anesthesia...  相似文献   
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Although the impact of dopamine on reward learning is well documented, its influence on other aspects of behavior remains the subject of much ongoing work. Dopaminergic drugs are known to increase risk-taking behavior, but the underlying mechanisms for this effect are not clear. We probed dopamine''s role by examining the effect of its precursor L-DOPA on the choices of healthy human participants in an experimental paradigm that allowed particular components of risk to be distinguished. We show that choice behavior depended on a baseline (ie, value-independent) gambling propensity, a gambling preference scaling with the amount/variance, and a value normalization factor. Boosting dopamine levels specifically increased just the value-independent baseline gambling propensity, leaving the other components unaffected. Our results indicate that the influence of dopamine on choice behavior involves a specific modulation of the attractiveness of risky options—a finding with implications for understanding a range of reward-related psychopathologies including addiction.  相似文献   
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There are limitations to the sensitivity and specificity of conventional two-dimensional echocardiograms in making an accurate diagnosis in certain patient populations. This led to the development of specific contrast-enhancing agents with the following characteristics: small enough to cross the pulmonary capillary bed, remain stable throughout the length of the procedure, do not dissolve in blood, and rapidly cleared from the body with low toxicity. Unfortunately, the use of contrast echocardiography has not taken off as expected. The low take-up rate among clinicians can largely be attributed to the black box warning by the United States Food and Drug Administration in 2007, after the coincidental occurrence of four patient deaths and about 190 severe cardiopulmonary reactions shortly after contrast agent administration. In this article, we address the clinical safety of contrast agents, share our institution’s experience in using it and elaborate on the clinical indications of contrast echocardiography.  相似文献   
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Abstract

Objective

Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients’ preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies.  相似文献   
7.
Denture stomatitis is a common recurring problem of the denture wearers. The aetiology of the disease includes infection, trauma and probably a defect in the host defence mechanism. Current thinking suggests an interplay of most of these factors in the pathogenesis of the disease. The extent of interplay of these factors is still a controversy. Candida albicans has been implicated as the causative organism. However, in the light of recent research it is debatable if it is the only causative organism. Recently, cases resistant to antifungal therapy have been reported. In such cases other micro-organisms have been isolated. At the moment, comprehensive management includes meticulous denture hygiene together with anti-fungal or antibacterial therapy and correction of denture faults.  相似文献   
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The in vitro pH changes in root dentin over a period of 2 weeks was investigated in 48 extracted bicuspids after intracanal placement of either Roeko Calcium Hydroxide Plus Points, aqueous calcium hydroxide paste, or gutta-percha points (control group) after root canal preparation. Microelectrodes were placed in outer and inner root dentin at cervical, middle, and apical thirds of the root to measure the pH at 1 h, 2 h, 3 h, 1 day, 3 days, 7 days, and 14 days. Roeko Calcium Hydroxide Plus Points reached a peak inner dentine pH of 11.67 and a peak outer dentine pH of 10.82 at 3 h. In addition, Roeko Calcium Hydroxide Plus Points maintained an outer dentine pH above 9.5 for approximately 2 days, whereas the aqueous calcium hydroxide paste did not reach this pH. However, the alkalinity in dentin with Roeko Calcium Hydroxide Plus Points was maintained for 7 days only, whereas aqueous calcium hydroxide paste maintained an alkaline environment throughout the 2-week period.  相似文献   
9.
Four alloys used for the construction of porcelain-fused-to-metal restorations were tested at high temperatures (1000 degrees C) so that loss of properties could be ascertained. In addition, thin flat plates of metal (30 x 11 x 1 mm) with a 9-mm recess and a metal thickness of 0.35 mm were processed for porcelain application and distortion measured at 15 points along the surface prior to and following each firing cycle. Yield and ultimate tensile strengths and elongation were determined on specimens at room temperature and at 1000 degrees C. None of the alloys tested showed a great amount of distortion during the various firing cycles, yet they showed increased change with each successive heating. The greatest distortion occurred with Jelenko "O" alloy. When the mechanical properties were compared, there was a marked loss of both yield and ultimate strength values for each alloy (Jelenko "O"-Y.S., 95.64%, U.T.S., 96.22%; Olympia--Y.S., 95.08%, U.T.S., 96.76%; Tempo--Y.S., 91.23%, U.T.S., 93.46%; Biobond II--Y.S., 83.72%, U.T.S., 86.21%). Percent elongation increased by 272% with Biobond II and 370% with Jelenko "O", whereas Tempo and Olympia increased by 120 and 155%. It is apparent that the palladium-based alloy and the nickel-chromium-based alloy have higher mechanical properties at the temperature where porcelain will be applied.  相似文献   
10.
Professional assessment of facial profile attractiveness.   总被引:2,自引:0,他引:2  
INTRODUCTION: The aim of this study was to compare the assessments of Chinese facial profile attractiveness by orthodontists and oral surgeons. METHODS: The sample comprised 31 dental professionals (20 orthodontists, 11 oral surgeons) in an Asian community. Facial profile photographs and lateral cephalometric radiographs of 2 Chinese adults (1 man, 1 woman) with normal profiles, Class I incisor relationships, and Class I skeletal patterns were digitized. The digital images were modified by altering cephalometric skeletal and dental hard tissue Chinese normative values in increments of 2 standard deviations in the anteroposterior plane to obtain 7 facial profiles for each sex. The images were bimaxillary protrusion, protrusive mandible, retrusive mandible, normal profile (Class I incisor with Class I skeletal pattern), retrusive maxilla, protrusive maxilla, and bimaxillary retrusion. The Mann-Whitney U test was used to determine professional differences in assessment. Multiple regression analysis was performed with age, professional status, sex, and number of years in practice as independent variables. RESULTS AND CONCLUSIONS: A strong correlation was found in the profile assessment between orthodontists and oral surgeons. Normal and bimaxillary retrusive Chinese male and female profiles were judged to be highly attractive by orthodontists and oral surgeons. Chinese male and female profiles with protrusive mandibles were judged the least attractive. There was a difference in professional opinion about the most attractive male profile (P < .05), with orthodontists preferring a flatter profile and oral surgeons preferring a fuller normal Chinese profile. Sex of dental professionals and number of years in clinical practice were found to affect profile rankings.  相似文献   
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