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OBJECTIVES: The purpose of this study was to evaluate the prognostic value of assessing right ventricular (RV) wall motion abnormalities during stress echocardiography (SE). BACKGROUND: The results of SE are usually interpreted based on wall motion abnormalities of the left ventricle (LV). There is increasing recognition of the prognostic importance of RV. However, RV is still a "forgotten" chamber during routine SE. METHODS: We evaluated 2,703 patients referred for SE. The LV was evaluated on a 16-segment model 5-point scale and the RV was evaluated on a 3-segment model 5-point scale for wall motion abnormalities. An abnormal RV or LV was defined as one with new (ischemic) or fixed (infarction) wall motion abnormalities. Follow-up (2.7 +/- 1.0 years) for confirmed myocardial infarction and cardiac death (n = 122) were obtained. RESULTS: An abnormal RV was seen in 112 patients (4%). In the presence of an abnormal LV, patients with abnormal RV had a worse prognosis than those with normal RV. Abnormal RV was a significant predictor of events (adjusted hazard ratio 2.69, 95% confidence interval 1.22 to 5.92; p = 0.014) independent of LV ischemia and ejection fraction. A forward conditional Cox model showed that peak RV wall motion score index provided incremental prognostic value over rest and conventional SE variables (global chi-square increased from 141.4 to 161.8 to 197.0; p < 0.0001 and p = 0.006, respectively). CONCLUSIONS: In patients referred for SE, RV wall motion analysis provides prognostic value independent of LV ischemia and ejection fraction and provides incremental value over rest and conventional SE variables. Right ventricular wall motion analysis should be routinely performed in patients referred for SE for effective risk stratification.  相似文献   
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Introduction  

Status epilepticus (SE) is a medical emergency requiring prompt treatment to try to limit mortality and improve outcome. So far, newer antiepileptic drugs (AED) have not assumed a noticeable role in the treatment of SE. This may be in part due to the lack of IV forms for the newer AEDs. The IV form of Levetiracetam (IV-LEV) has recently become available and has a potential role in the treatment of SE.  相似文献   
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INTRODUCTION: Choosing surgery as a career is declining among U.S. medical students. The 8-wk third year surgery clerkship at our institution can be an intense learning experience, and we hypothesized that during this clerkship medical student quality-of-life would drop significantly from baseline, and that this drop would be greater among certain subgroups, such as women students not interested in pursuing a surgical career, and those who place a high value on a controllable lifestyle. METHODS: At clerkship orientation (baseline), students were asked to complete a survey that measured quality-of-life on an 84-point scale, and depression on a 40-point scale. The quality-of-life scale was composed of select questions from the Medical Outcomes Study, and the Harvard Department of Psychiatry/NDSD brief screening instrument was used to measure depression. Students were also asked the typical number of hours they slept per night. Demographics, attitude toward a controllable lifestyle, and top three specialties of interest were also gathered at baseline. On week 6 of the clerkship, students were surveyed on the same quality-of -life and depression scales, and asked average hours of sleep per night for the previous week. RESULTS: From June 2005 through December 2006, 143 of 177 (81%) students agreed to participate, and after exclusions for missing data, 137 students were included in the analysis. Sixty-nine students were women (51%), and the average age was 25.8 (sd 2.6). Mean quality-of-life at baseline was 57.0 (sd 11.3) and at week 6 was 50.4 (sd 10.1) representing a statistically significant average decline of 6.6 points (P < 0.0001). Mean depression at baseline was 14.4 (sd 3.8) and at week 6 was 15.1 (sd 3.6), representing a small but significant average decline of 0.7 points (P = 0.0155). Mean sleep at baseline was 6.3 h/night (sd 0.9) and at week 6 was 5.7 h/night (sd 1.2), representing a statistically significant average decline of 0.6 h/night (P < 0.0001). Declines were similar on all outcomes between men versus women, those who ranked surgery in their top three career choices versus those who did not, and those who ranked controllable lifestyle as "very important" versus all other categories. CONCLUSION: Quality-of-life and sleep declines and depression increases significantly in third-year medical students from orientation to week 6 of their surgery clerkship at our institution. We look forward to studying quality-of-life on other clerkships for comparison, assessing whether the magnitude of this decline in quality-of-life predicts students avoiding a future career in surgery, and testing interventions to prevent this decline in quality-of-life during the clerkship.  相似文献   
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Trichloroethylene (TCE), an industrial solvent, is a major environmental contaminant. Histopathological examinations revealed that TCE caused liver and kidney toxicity and carcinogenicity. However, biochemical mechanism and tissue response to toxic insult are not completely elucidated. We hypothesized that TCE induces oxidative stress to various rat tissues and alters their metabolic functions. Male Wistar rats were given TCE (1000 mg/kg/day) in corn oil orally for 25 d. Blood and tissues were collected and analyzed for various biochemical and enzymatic parameters. TCE administration increased blood urea nitrogen, serum creatinine, cholesterol and alkaline phosphatase but decreased serum glucose, inorganic phosphate and phospholipids indicating kidney and liver toxicity. Activity of hexokinase, lactate dehydrogenase increased in the intestine and liver whereas decreased in renal tissues. Malate dehydrogenase and glucose-6-phosphatase and fructose-1, 6-bisphosphatase decreased in all tissues whereas increased in medulla. Glucose-6-phosphate dehydrogenase increased but NADP-malic enzyme decreased in all tissues except in medulla. The activity of BBM enzymes decreased but renal Na/Pi transport increased. Superoxide dismutase and catalase activities variably declined whereas lipid peroxidation significantly enhanced in all tissues. The present results indicate that TCE caused severe damage to kidney, intestine, liver and brain; altered carbohydrate metabolism and suppressed antioxidant defense system.  相似文献   
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