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91.
OBJECTIVES: We conducted a collaborative cohort study to evaluate the predictive power of microvolt T-wave alternans (TWA) in patients with preserved left ventricular ejection fraction (LVEF) after myocardial infarction (MI). BACKGROUND: There is little information available about the prognostic value of risk stratification markers in this population. Although these patients have a relatively good prognosis, identifying high-risk patients is important in clinical practice. METHODS: This study enrolled 1,041 post-MI patients with an LVEF > or =40% (average 55 +/- 10%). Microvolt TWA testing was performed 48 +/- 66 days after acute MI, and 10 other risk variables were also evaluated. The end points were prospectively defined as sudden cardiac death or life-threatening arrhythmic events. RESULTS: During a follow-up of 32 +/- 14 months, 38 patients (3.7%) died of nonarrhythmic causes and were not considered for analysis. Of the 1,003 evaluable patients, 18 (1.8%) reached an end point. Microvolt TWA was positive in 169 patients (17%), negative in 747 (74%), and indeterminate in 87 (9%). A positive microvolt TWA test, nonsustained ventricular tachycardia, and ventricular late potentials were predictors of events, and percutaneous coronary intervention decreased the risk rate. On multivariate analysis, a positive microvolt TWA test was the most significant predictor, with a hazard ratio of 19.7 (p < 0.0001). This marker had the highest sensitivity and negative predictive value for events. CONCLUSIONS: In patients with preserved cardiac function, the incidence of indeterminate results of microvolt TWA is low, and a positive test result is associated with arrhythmic events. Microvolt TWA could be used for risk stratification in this low-risk population.  相似文献   
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We describe a case with macular hole (MH) associated with Vogt-Koyanagi-Harada (VKH) disease. A 71-year-old Japanese woman presented with visual loss and headaches. The best-corrected visual acuity (BCVA) was 0.02 in the right eye (RE) and 0.1 in the left eye (LE). The patient was diagnosed with VKH based on circumferential choroidal detachments, multiple serous retinal detachments, and optic disc hyperemia. The multiple serous retinal detachments improved with high-dose corticosteroid therapy and gradual tapering. The BCVA was recovered to 1.2/0.7 in the RE/LE. Six weeks after the initial administration of steroid, vitreomacular traction was found by optical coherence tomography in the LE, which progressed to stage 4 MH with the BCVA of 0.2 in the LE. Twenty-three weeks after the initial treatment, vitrectomy was performed with the standard surgical procedures, including inner limiting membrane peeling around the fovea and air tamponade. The MH was closed successfully and the BCVA was 0.4 in the LE 5 weeks after the vitrectomy. This is the first report of a case with MH secondary to the acute uveitic stage of VKH. Successful closure of MH was achieved with the standard surgical intervention for an idiopathic MH. To conclude, at the early stage of VKH, there is a possibility of MH formation due to the rapid progress of vitreous traction following the inflammation, and the surgical procedure could be effective to resolve this secondary disorder.Key Words: Macular hole, Vogt-Koyanagi-Harada disease, Uveitis, Vitrectomy  相似文献   
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We have shown previously that Cyp11b1, an 11beta-hydroxylase responsible for glucocorticoid biosynthesis in the adrenal gland, was induced by cAMP in androgen-producing Leydig-like cells derived from mesenchymal stem cells. We found that Cyp11b1 was induced in male Leydig cells, or female theca cells, when human chorionic gonadotropin was administered in immature mice. Expression of Cyp11b1 in rodent gonads caused the production of 11-ketotestosterone (11-KT), a major fish androgen, which induces male differentiation or spermatogenesis in fish. As in teleosts, plasma concentrations of 11-KT were elevated in human chorionic gonadotropin-treated mice. In contrast to teleosts, however, plasma concentrations of 11-KT were similar in both sexes, despite levels of testosterone, a precursor substrate, being about 20 times higher in male mice. Because expression of 11beta-hydroxysteroid dehydrogenase type 2, was much higher in the mouse ovary than in the testis, conversion of testosterone into 11-KT may occur more efficiently in the ovary. In a luciferase reporter system that was responsive to and activated by androgens, 11-KT efficiently activated mammalian androgen receptor-mediated transactivation. Our results suggest that the androgen metabolic pathway is conserved between teleosts and mammals, despite sexual dominance and reproductive functions of 11-KT being altered during evolution.  相似文献   
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BACKGROUND: Recent studies have shown that a global flow abnormality affects the entire coronary tree in patients with acute coronary syndrome (ACS), and that it is associated with adverse outcomes. Postprandial hyperglycemia is also thought to promote coronary endothelial dysfunction, as well as the release of inflammatory and vasoconstrictive factors. This study used the corrected Thrombolysis In Myocardial Infarction frame count (CTFC) to investigate whether optimal control of postprandial hyperglycemia improves pan-coronary flow. METHODS AND RESULTS: Eighty ACS patients with postprandial hyperglycemia who had successful coronary intervention and who had undergone a 75-g oral glucose tolerance test (OGTT) were included. A second OGTT and angiogram were performed 8 months after procedures. The patients were divided according to postprandial glycemia after the second 75-g OGTT; optimal postprandial hyperglycemia was defined as a 2-h blood glucose concentration <7.8 mmol/L. Changes in the CTFC of culprit/non-culprit arteries, glucose response, and other clinical variables were compared. Forty patients improved to an optimal control at 8 months. In the culprit artery, the 8-month angiogram revealed a significantly improved CTFC among those with optimal control compared with the initial angiogram (30+/-9 vs 24+/-12, p<0.05). In contrast, the CTFC was not evidently improved among patients with suboptimal control. The CTFC at 8 months had thus obviously improved more in patients with optimal, than with suboptimal control (24+/-12 vs 30+/-11, p<0.05). CONCLUSION: Optimal control of postprandial hyperglycemia improves epicardial blood flow in both arteries and this beneficial effect might be from improved coronary endothelial function.  相似文献   
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Oral Radiology - To ascertain the effects of exposure parameters (tube current and tube voltage) and the gutta-percha cone (GPC) size on root fracture-like artifacts obtained with cone-beam...  相似文献   
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