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Twenty-two patients (19 men) with heart failure (16 ischemic, 6 dilated cardiomyopathy; mean age of 67 +/- 6 years) in New York Heart Association classes I (2 patients), II (18 patients), and III (2 patients) under optimal therapy were strictly monitored after carvedilol supplementation. The Tei index decreased significantly from 0.87 +/- 0.17 to 0.53 +/- 0.29 (p <0.03). Conversely, the ejection fraction and transmitral Doppler flow analysis did not show significant improvement, despite a trend toward the amelioration of the ejection fraction, the E-/A-wave ratio, and atrial contribution. The Tei index could represent an earlier marker to evaluate drug-induced left ventricular function improvement in patients with heart failure and could represent a more sensitive tool to monitor left ventricular function during drug interventions.  相似文献   
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The diagnostic usefulness of intraepithelial cells with irregular nuclear contours (CINC) (squiggle cells) in esophageal endoscopic biopsies was investigated in 76 children (range age: 6 months-12 years) with gastroesophageal reflux disease. A further 20 subjects (range age: 10 months-11 years) served as controls. Based on the microscopic changes of the esophagus, according to traditional histological criteria, four groups of patients were identified: esophagitis was severe in 27, moderate in 20, mild in 21, and 8 patients had no clear-cut evidence of microscopic esophagitis. Data are given as mean±sd. Intraepithelial CINC had an immunohistochemical profile consistent with T lymphocytes. Patients with severe esophagitis had a CINC density (number per high-power field) (9.0±3.5) significantly higher than patients with mild esophagitis (7.0±3.0) and those without evidence of microscopic esophagitis (6.5±1.9) (P<0.05), but not different from those with moderate esophagitis (8.0±3.6); in all patient groups the CINC density was higher than in controls (2.2±0.3) (P<0.01). The percentage of reflux at 24-hr intraesophageal pH monitoring was higher in severe esophagitis patients (11.4±6.0) as compared to the other groups (moderate: 7.8±6.3; mild: 6.5±3.6; no microscopic esophagitis: 6.3±2.0;P<0.05). There was no correlation between CINC density and the amount of intraesophageal acid exposure in all patients. Furthermore, 27 of our patients had a normal intraesophageal acid exposure at the prolonged pH test (24-hr % of reflux 4.5): the CINC density was significantly higher in them than in the controls. We conclude that intraepithelial CINC in esophageal endoscopic biopsies from children with reflux disease represent a sensitive and early criterion of esophageal mucosa damage; they should be scanned in addition to the traditional histological parameters of acid-related esophageal inflammation.Presented in an abstract form at the 28th Annual Meeting of the European Society of Paediatric Gastroenterology and Nutrition, Jerusalem, May 28–June 1, 1995.  相似文献   
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The authors performed the experimental model of infarct-like myocardial lesions in rats treated with large doses of ISP. Myocardial necrosis was assessed on the basis of serum enzyme changes as well as of gross and microscopic findings. The infarct size was measured by a direct enzymatic method assaying creatine kinase (CK) depletion in infarcted myocardium. Pretreatment of the infarcted rats with antiplatelet (Lysin Acetyl Salicylate) or calcium antagonist drugs (Verapamil or Nifedipine) allowed the reduction of the necrotic area. Since a smaller size of infarct was achieved through different types of interventions it should be suggested that ISP-myocardial damage is due to several effects of the drug involving metabolic, vascular and/or coagulative patterns.  相似文献   
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We studied the relation between the glutathione (GSH) system and cell proliferation in a model of smooth muscle cells (SMC) derived from the thoracic aorta of 4–6-week-old (young) and 15-month-old (aged) rats. SMC from aged rats showed greater levels of total non-protein thiol compounds (T-SH), increased glutathione transferase (GST) and increased glutathione reductase (GSSG-Red) activities compared with cells from young rats. These changes were associated with an increased proliferation rate of SMC from aged rats. To evaluate the role of GSH on cell proliferation better, a specific inhibitor of gamma-glutamyl-cystein synthetase, -buthionine-SR-sulphoximine (BSO) was used. BSO showed a dose-dependent inhibition of cell growth, with an IC50 of 10−4 M, after 48–72 h of incubation. Removal of BSO restored cell growth, further suggesting a link between GSH levels and vascular cell proliferation. The inhibitory effect of BSO was about two times greater on SMC from young than on SMC from aged rats. BSO showed 56% inhibition on the proliferation of SMC from young rats and 32% inhibition on SMC from aged rats (10−4 M, 72 h of incubation). A parallel reduction of GSH levels of 38% and 19% for SMC from young and aged rats, respectively, was observed, suggesting that age-related factors may influence the involvement of GSH system in cell proliferation.  相似文献   
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Left ventricular dysfunction is in most cases the consequence of myocardial ischemia. It may occur transiently during an attack of angina and usually it is reversible. It may persist over hours or even days in patients after an episode of ischemia followed by reperfusion, leading to the so-called condition of stunning. In patients with persistent limitation of coronary flow, left ventricular dysfunction may be present over months and years, or indefinitely in subjects with fibrosis, scar formation, and remodeling after myocardial infarction. Bowever, chronic left ventricular dysfunction does not mean permanent or irreversible cell damage. Bypoperfused myocytes can remain viable but akinetic. This type of dysfunction has been calledhibernating myocardium. The dysfunction due to hibernation can be partially or completely restored to normal by reperfusion. It is, therefore, important to clinically recognize a hibernating myocardium. In the present article we evaluate stunning and hibernation with respect to clinical decision making and, when possible, we refer to our ongoing clinical experience.  相似文献   
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Carbapenem antibiotics were first introduced in the 1980s and have long been considered the most active agents for the treatment of multidrug-resistant gram-negative bacteria. Over the last decade, carbapenem-resistant Enterobacteriaceae (CRE) have emerged as organisms causing spontaneous bacterial peritonitis. Infections caused by CRE have shown a higher mortality rate than those caused by bacteria sensitive to carbapenem antibiotics. Current antibiotic guidelines for the treatment of spontaneous bacterial peritonitis are insufficient, and rapid de-escalation of empiric antibiotic treatment is not widely recognized. This review summarizes the molecular characteristics, epidemiology and possible treatment of spontaneous bacterial peritonitis caused by CRE.  相似文献   
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