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Two experiments investigated the effect of facial expressions on clinically-relevant ambiguity resolution in a nonclinical sample. Experiment 1 investigated the effect of negative facial feedback (frowning) on a basic threat-interpretation bias procedure using a homophone spelling task and found that participants in a frowning condition interpreted significantly more threat/neutral homophones as threats than did participants in a neutral control condition. Experiment 2 investigated how frowning affected interpretation of bodily sensations. The findings indicated that participants in the frowning condition generated fewer positive consequences for bodily sensation scenarios and also rated the imagined bodily sensations as more negative and more of a cause for health concern. These effects could not simply be explained by differences in self-reported mood or by demand characteristics. These findings suggest that facial expressions have a moderating effect on the cognitive processes that contribute to clinically-relevant ambiguity resolution, and this has implications for clinical interventions.  相似文献   
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This study investigated the role of KATP channels in morphine‐induced antinociception and hepatic oxidative stress in acute and inflammatory pain. The KATP channel modulators (KATP channel opener, diazoxide 100 mg/kg, p.o, and KATP channel blocker, glibenclamide, 3 mg/kg i.p.) were administered with morphine (80 mg/kg, i.p.). Antinociception was assessed by the tail‐flick and formalin tests in rats and measured by the area under the curve values and the maximum percent effect for 3 h. The indices of hepatic oxidative stress: glutathione, glutathione peroxidase, and malondialdehyde were then determined in the liver homogenates obtained from the treated animals. In both tests, glibenclamide antagonized morphine‐induced antinociception, whereas diazoxide augmented it in the tail‐flick test only. In the formalin test, glibenclamide alone has a significant hyperalgesic effect, whereas diazoxide decreased the number of flinches. Coadministration of glibenclamide with morphine antagonized the hepatotoxic effect of morphine in both animal models. In the tail‐flick test, glibenclamide administered alone significantly increased malondialdehyde's level. Coadministration of diazoxide with morphine increased glutathione level in the formalin test. Diazoxide administered alone exacerbated the hepatic oxidative stress in both animal models. These findings suggest a role of KATP channel modulators on morphine‐induced antinociception and hepatic oxidative stress. The administration of glibenclamide may prevent morphine‐induced hepatotoxicity. The effectiveness of diazoxide in the management of pain is limited due to its deleterious effect on the liver. However, the interaction of the KATP channel modulators with morphine depends on the differential sensitivity to the pain stimulus.  相似文献   
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BACKGROUND: Cold preservation produces hepatic injury that is difficult to assess during early reperfusion. The value of reperfusion plasma choline phospholipid in predicting subsequent organ function is documented in these studies. MATERIALS AND METHODS: Livers of female Yorkshire pigs were prepared for transplantation. After 2 h of cold ischemia the reperfusion plasma was evaluated for choline phospholipid and cholesterol. These values were correlated with bile secretion, hepatic hemodynamics, oxygen uptake, and plasma sorbitol dehydrogenase levels. RESULTS: The isolated porcine liver demonstrates a rapid efflux of choline phospholipids into plasma during early reperfusion after cold preservation. After this initial efflux no subsequent plasma increment occurred. These choline-phospholipid increments were isolated in plasma higher density (d > 1.063) lipoproteins and were not accompanied by equivalent increases in cholesterol. Neither biliary reflux nor lecithin cholesterol acyl transferase abnormalities contributed appreciably to the phospholipid increments in reperfusion plasma. Livers with the largest efflux of choline phospholipids had the most impaired circulatory and bile secretory function at 4 h of reperfusion. CONCLUSION: The immediate increase of choline phospholipids, particularly lysophosphatidylcholine, in reperfusion plasma after cold ischemia provides an index of the injury occurring during this interval and correlates with early organ function.  相似文献   
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INTRODUCTION: Computed tomography (CT) scans are often used in the evaluation of patients with blunt trauma. This study identifies the clinical features associated with further diagnostic information obtained on a CT chest scan compared with a standard chest X-ray in patients sustaining blunt trauma to the chest. METHODS: A 2-year retrospective survey of 141 patients who attended a Level 1 trauma centre for blunt trauma and had a chest CT scan and a chest X-ray as part of an initial assessment was undertaken. Data extracted from the medical record included vital signs, laboratory findings, interventions and the type and severity of injury. RESULTS: The CT chest scan is significantly more likely to provide further diagnostic information for the management of blunt trauma compared to a chest X-ray in patients with chest wall tenderness (OR=6.73, 95% CI=2.56, 17.70, p<0.001), reduced air-entry (OR=4.48, 95% CI=1.33, 15.02, p=0.015) and/or abnormal respiratory effort (OR=4.05, 95% CI=1.28, 12.66, p=0.017). CT scan was significantly more effective than routine chest X-ray in detecting lung contusions, pneumothoraces, mediastinal haematomas, as well as fractured ribs, scapulas, sternums and vertebrae. CONCLUSION: In alert patients without evidence of chest wall tenderness, reduced air-entry or abnormal respiratory effort, selective use of CT chest scanning as a screening tool could be adopted. This is supported by the fact that most chest injuries can be treated with simple observation. Intubated patients, in most instances, should receive a routine CT chest scan in their first assessment.  相似文献   
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