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61.
Serum gamma-glutamyltransferase (GGT) activity is a marker of oxidative stress and activity is associated with cardiovascular disease. Carotid intima-media thickness (IMT) is a noninvasive predictor of atherosclerosis. We investigated the association between serum GGT activity and carotid IMT. Fifty-five persons who had normal liver function tests were consecutively enrolled. Carotid IMT was evaluated in the right and left common carotid arteries. The averaged values of carotid IMT and serum GGT activity were compared. Serum GGT activity correlated with carotid IMT (r = .396, P = .003). Serum GGT activities were increased in patients with carotid intimal hyperplasia compared with those without intimal hyperplasia (20.3 ± 11.2 vs 34.3 ± 16.1 U/L; P = .001). Serum GGT activity is associated with carotid IMT. This finding supports the concept that elevated serum GGT activity is a marker of atherosclerosis.  相似文献   
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Legged locomotion on flowing ground (e.g., granular media) is unlike locomotion on hard ground because feet experience both solid- and fluid-like forces during surface penetration. Recent bioinspired legged robots display speed relative to body size on hard ground comparable with high-performing organisms like cockroaches but suffer significant performance loss on flowing materials like sand. In laboratory experiments, we study the performance (speed) of a small (2.3 kg) 6-legged robot, SandBot, as it runs on a bed of granular media (1-mm poppy seeds). For an alternating tripod gait on the granular bed, standard gait control parameters achieve speeds at best 2 orders of magnitude smaller than the 2 body lengths/s (≈60 cm/s) for motion on hard ground. However, empirical adjustment of these control parameters away from the hard ground settings restores good performance, yielding top speeds of 30 cm/s. Robot speed depends sensitively on the packing fraction and the limb frequency ω, and a dramatic transition from rotary walking to slow swimming occurs when becomes small enough and/or ω large enough. We propose a kinematic model of the rotary walking mode based on generic features of penetration and slip of a curved limb in granular media. The model captures the dependence of robot speed on limb frequency and the transition between walking and swimming modes but highlights the need for a deeper understanding of the physics of granular media.  相似文献   
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Cor triatriatum dexter, in which the right atrium (RA) is divided into two chambers by a membrane, is a very rare congenital abnormality. In this abnormality, there is a high incidence of associated congenital abnormalities, particularly of the right heart. We presented two men with cor triatriatum dexter. Echocardiography is discussed as a non-invasive diagnostic tool.  相似文献   
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This study determined whether prolonged QRS duration (QRSd; > or =120 ms) is an independent predictor of low cardiac output syndrome (LCOS) in patients with low left ventricular (LV) ejection fraction (EF) who underwent isolated coronary artery bypass grafting (CABG). Abnormal LV systolic function places patients at greater risk for developing LCOS after isolated CABG. In patients with this form of ventricular function impairment, prolonged QRSd is associated with adverse hemodynamic effects. Clinical, operative, and outcome data from 190 consecutive patients with LVEF <50% who underwent isolated CABG (mean 62 +/- 9 years of age) were retrospectively analyzed. For all patients, preoperative QRSd was determined. LCOS was the primary outcome investigated. Fifty-seven patients (30%) developed LCOS. Compared with the subgroup without LCOS, the subgroup with this syndrome had significantly larger proportions of patients with LVEF <30% and prolonged QRSd. In addition, the group that developed LCOS had a longer mean QRSd (117 +/- 25 vs 102 +/- 17 ms, respectively, p = 0.00003) and a significantly higher frequency of adverse postoperative outcomes. Hospital stay was significantly longer in the subgroup with LCOS than in the subgroup without. Multivariate logistic regression analysis identified prolonged QRSd as the most significant predictor of LCOS. LVEF <30%, diuretic therapy, and preoperative risk score (European System for Cardiac Operative Risk Evaluation) were also identified as independent predictors of LCOS. In conclusion, in patients with impaired LV systolic function, prolonged QRSd is a highly significant predictor of LCOS development after isolated CABG.  相似文献   
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The objective of this study was to investigate the effects of types of dialysis treatments on hepatitis C virus infection and the epidemiologic properties of hepatitis C virus (HCV) infection at three Baskent University hospitals, in Ankara, Adana, and Izmir, Turkey, in 655, 326, and 118 patients with end-stage renal disease, respectively. One hundred thirty patients with HCV viremia among 271 patients with end-stage renal disease seropositive for HCV were included in this cross-sectional study. HCV RNA-positive patients were classified according to the renal replacement therapies (hemodialysis or continuous ambulatory peritoneal dialysis), and viral load, transaminase levels, and distribution of genotypes were compared between these subgroups. In the continuous ambulatory peritoneal dialysis group, 26 of 165 patients (16%) were serum anti-HCV positive, and 11 of 26 patients (42%) were serum HCV RNA positive. Twenty-six percent of the patients undergoing hemodialysis were anti-HCV positive, and 49% were HCV RNA positive. The prevalence of genotype 1b was 68% and 73% for patients in the continuous ambulatory peritoneal dialysis and hemodialysis groups, respectively. No significant differences were found between the genotype 1b and the non-1b groups or between different dialysis types with regard to age and sex and serum aspartate transaminase, alanine aminotransferase, and HCV RNA levels. We conclude that HCV seropositivity may differ between different types of dialysis treatments, although viral load and genotypes may be similar in persons with end-stage renal disease and those without.  相似文献   
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Multinodular hydropic leiomyoma (MHL) of the uterus is one of the rarest variants of uterine leiomyomas and can create some diagnostic problems. Only five cases have been reported previously. We describe an MHL with perinodular hydropic degeneration in a 48-year-old woman. Gross examination revealed a large and predominantly intramural, edematous multinodular uterine tumor and extrauterine, small grape-like nodules overlying the lateral surface of the uterine serosa. Histologically, the tumor was composed of extra-intrauterine benign, small smooth muscle nodules with perinodular hydropic degeneration, prominent intramural dissecting growth pattern, and satellite nodules closely resembling vascular invasion. Immunohistochemically, these cells stained for desmin, smooth muscle actin and vimentin. The patient had no evidence of disease for 18 months after hysterectomy. Multinodular hydropic leiomyoma is a clinically benign tumor and should not be confused with intravenous leiomyomatosis and some other unusual leiomyoma variants.  相似文献   
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