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31.
Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. The aim of this study was to determine the value of mitral inflow A-wave velocity, performed at 24 hours after CV in estimation of AF recurrence. The study group consisted of 187 consecutive patients with nonvalvular atrial fibrillation, who had been cardioverted to SR from 1998 to 2000. Transthoracic echocardiography was performed in all cases recruited for the study 24 hours after CV. Left atrial (LA) diameter, left ventricular ejection fraction, and mitral inflow A-wave velocity were measured. The patients were evaluated in five groups according to their recurrence time (<30 days, 31-90 days, 91-180 days, 181-365 days, and >365 days). Maintenance of SR was determined to have a negative linear correlation with age (r =-0.97, P = 0.006), LA diameter (r =-0.93, P = 0.02), and AF duration (r =-0.93, P = 0.02), while having a positive linear correlation with mitral inflow A-wave velocity (r = 0.96, P = 0.008). In the maintenance of sinus rhythm, age, LA diameter, and AF duration were not affected from the method of CV, while mitral inflow A-wave velocity was found to be affected with the method of CV. No relationship was determined between mitral inflow A-wave velocity and the maintenance of sinus rhythm in those performed electrical cardioversion, while frequency of recurrence was found to be higher in those with slow mitral inflow A-wave velocity who were performed pharmacological cardioversion (r = 0.89, P = 0.004). In conclusion, age, duration of AF, LA diameter, and the mitral inflow A-wave velocity can be used to predict the maintenance of SR after CV.  相似文献   
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Although it has been demonstrated that maternal epilepsy has some harmful effects on newborn individuals, current data concerning the effects of epileptic phenomena in pregnant mothers on newborn pups are still limited. This study was undertaken to investigate the changes in the cerebellum of newborns of pinealectomized rats subjected to experimental epilepsy during pregnancy. In our study, the rats were randomly divided into six groups: intact control group, anesthesia control group, epilepsy group, melatonin-treated epileptic group, surgical pinealectomy group, and group of melatonin treatment following pinealectomy procedure. At 1 month after pinealectomy, an acute grand mal epileptic seizure was induced by 400 IU penicillin-G administration into their intrahippocampal CA3 region during the 13th day of their pregnancy in all animals except intact control group. On the neonatal first day, pups were perfused transcardially and the cerebellums removed were processed for light microscopic and immunohistochemical studies. Normal migration and maturation were determined in the postnatal rat cerebellum in both intact control and anesthesia (ketamine-xylazine) control groups, but the morphological structure of cerebellum in the epilepsy control group corresponded to the early embryonal period. It was found that experimental epilepsy or pinealectomy procedure enhanced nestin immunoreactivity, but exogenous melatonin treatment (30 microg/100 g body weight, i.p.) following pinealectomy inhibited increased nestin expression induced by melatonin deprival in vermis region of newborn rat cerebellum (P < 0.001). Our results confirm that epileptic seizures during pregnancy may impair neurogenesis and neuronal maturation in newborns, which are more dramatic in the presence of melatonin deficiency during pregnancy, explaining more harmful effects of epileptic seizures to embryos of aged mothers. To the best of our knowledge, this is the first study reporting the effects of maternal epilepsy during pregnancy in pinealectomized rats on nestin immunoexpression in the newborn rat cerebellum.  相似文献   
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A 13 year-old boy with Prader-Willi syndrome and steatohepatitis presented with diabetic ketoacidosis 4 weeks after the initiation of growth hormone (GH) treatment. He did not have signs or symptoms of type 2 diabetes mellitus (DM2) before the initiation of GH treatment. Hyperglycemia resolved 2 months after discontinuation of GH. He redeveloped DM2 6 months later associated with excessive weight gain. Diabetic ketoacidosis as a rare complication of GH therapy emphasizes the importance of screening for carbohydrate intolerance before and during GH treatment in patients with Prader-Willi syndrome. Steatohepatitis may be the only manifestation of insulin resistance and warrants further evaluation.  相似文献   
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HYPOTHESIS: This study was conducted to compare the effectiveness of two anti-adhesive barriers (Seprafilm and Interceed) for reducing adhesions after thyroidectomy in a rat model. The anti-adhesive barriers are suggested for use in repeated surgeries in general and the gynecologic fields in particular. STUDY DESIGN: Controlled, randomized study. METHODS: Twenty-eight male Wistar Albino rats that underwent right subtotal thyroidectomy were randomly assigned to three groups. One group received Seprafilm (n = 10), and the other received Interceed (n = 10) as anti-adhesive barriers. The third group was the control group (n = 8). At postoperative day 14, the rats were killed under general anesthesia, and the surgical fields were evaluated for the adhesion formation. The extent of the adhesion formation is scored from 0 (no adhesions) to 2 (fibrous adhesions that required sharp dissection). Histopathologically, chronic inflammation, histiocyte, fibroblast, fibrosis, collagen, vascularization, granuloma, giant cell, and fat necrosis were examined. RESULTS: All the subjects in the control group, 7 of 10 in the Interceed group, and 4 of 10 in the Seprafilm group needed to be dissected bluntly or sharply. There was significant difference between the Seprafilm and the control group (P < .05) whereas there was no significant difference between the Interceed group and the control group (P > .05). When examined histopathologically, the criteria showing adhesion, such as fibrosis, fibroblast, and collagen were higher in the control group compared with the Seprafilm and Interceed groups. There was no significant difference between the Seprafilm and Interceed groups, whereas a significant difference was found between these two groups and the control group. CONCLUSION: This study suggests that both Seprafilm and Interceed decrease the incidence of posthyroidectomy adhesions in a rat model. Both agents showed no foreign body reaction.  相似文献   
36.
Measurement of ionized magnesium (IMg) provides an accurate assessment of the free form of Mg, which is the physiologically active form and is most reflective of the biologically active and not easily measurable intracellular Mg fraction. Plasma levels of IMg were measured by ion-selective electrode method in premature newborns with respiratory distress syndrome (RDS), and relationships and correlations between IMg levels and various demographic, prognostic and laboratory characteristics were investigated by comparing the premature newborns with (study group; n = 19) and without RDS (control group; n = 20) in the present study. The values of the postnatal arterial pH and base excess and plasma IMg levels were significantly different between the study and control groups, and the number of newborns with any morbidity was significantly higher in the study group. Within the study group there were significant negative correlations between the plasma IMg levels and the values of the umbilical cord arterial pH (r = -0.621, p = 0.005) and base excess (r = -0.746, p = 0.001), and the value of the postnatal arterial base excess (r = -0.585, p = 0.008). The newborns who died later had higher plasma IMg levels than those who survived (0.89 +/- 0.45 vs. 0.63 +/- 0.24 mmol/l, p = 0.026). These findings suggest that increase of plasma IMg may be due to extracellular movement of Mg, which is a principally intracellular ion, as a result of acidosis, hypoxia and probable cellular injury during the early course of RDS. The exact pathophysiological mechanism responsible for IMg increase, and whether determination of plasma IMg level, including umbilical cord blood IMg measurement, can be used as an early or predictive indicator of RDS in the diagnosis remain to be determined in further large-scale studies.  相似文献   
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Endothelin 1 concentrations in infants with meconium stained amniotic fluid   总被引:3,自引:0,他引:3  
Plasma endothelin 1 concentrations were determined in infants with meconium stained amniotic fluid. Plasma endothelin 1 concentration in the study group (5.23 pg/ml) was statistically higher than that in the control group (1.12 pg/ml). Cord blood pH and base excess values were significantly lower in infants with meconium stained amniotic fluid when compared with the control group. There was no correlation between endothelin 1 concentrations and pH or base excess values. Results suggest that meconium passage is not a physiological event, even if meconium stained infants appear to be clinically healthy.  相似文献   
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Background  Enoxaparin is an important molecule which had been using in prophylaxis and treatment of deep venous thrombosis. Also, it is showed that it prevents postsurgical peritoneal adhesions in rats. It is aimed to evaluate its effects on gastrointestinal wound healing. Methods  Thirty Wistar albino rats were divided into three groups as control, subcutan, and intraperitoneal enoxaparin groups. Left colon anastomoses were performed. On postoperative seventh day, anastomotic healing was evaluated by measuring anastomotic bursting pressure, tissue hydroxyproline levels, and histopathological examination. Results  The anastomotic bursting pressure was highest in subcutan enoxaparin group (p < 0.001), intraperitoneal enoxaparin group (p < 0.01) came the second, and the control group has the worst value. The hydroxyproline results were found nearly similar to the bursting pressure values (subcutan (p < 0.001) > intraperitoneal (p < 0.05) > control). Neovascularization in subcutan group (p < 0.001) has a statistically significant difference to other groups. Conclusion  Enoxaparin did not interfere with colonic anastomotic resistance but improved the intestinal wound healing.  相似文献   
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