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61.
BACKGROUND: Taurine, a potent antioxidant, has been reported to improve streptozotocin-induced diabetes mellitus, in which the development of diabetes results from an attack by oxygen free radicals on pancreatic beta cells. However, taurine also increases the excretion of cholesterol via conversion to bile acid and would be expected to improve insulin resistance. OBJECTIVE: The effects of taurine on insulin sensitivity were examined in a model rat of insulin resistance and type 2 diabetes-the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. DESIGN: Male OLETF rats were divided into 2 groups at the age of 16 wk: a taurine-supplemented group and an unsupplemented group. As a nondiabetic control, Long-Evans-Tokushima-Otsuka rats were used. An oral-glucose-tolerance test and hyperinsulinemic euglycemic clamp were performed at the ages of 23 and 25 wk. RESULTS: The OLETF rats had hyperglycemia and insulin resistance and they had a greater accumulation of abdominal fat than did control rats. Abdominal fat accumulation, hyperglycemia, and insulin resistance were significantly lower in the taurine-supplemented group than in the unsupplemented group. Serum and liver concentrations of triacylglycerol and cholesterol were significantly higher in the OLETF rats than in the control rats and were significantly lower in the taurine-supplemented group than in the unsupplemented group, presumably because of the increased secretion of cholesterol into bile acid. Taurine-supplemented rats also showed higher nitric oxide secretion, evidenced by increased urinary excretion of nitrite. CONCLUSION: Taurine effectively improves metabolism in OLETF rats by decreasing serum cholesterol and triacylglycerol, presumably via increased secretion of cholesterol into bile acid and decreased production of cholesterol because of increased nitric oxide production.  相似文献   
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In the National Cancer Institute/Children's Cancer Group case-control study of childhood acute lymphoblastic leukemia (1989-1993), living in a home with a high-voltage wire code was not associated with disease risk. To further investigate risk near power lines, the authors analyzed distance to transmission and three-phase primary distribution lines within 40 m of homes and created an exposure index of distance and strength of multiple power lines (408 case-control pairs). Neither distance nor exposure index was related to risk of childhood acute lymphoblastic leukemia, although both were associated with in-home magnetic field measurements. Residence near high-voltage lines did not increase risk.  相似文献   
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用光化学沟通方法确证了从葡萄科植物蘡薁Vitis thunbergii(Vitaceae)中分离得到的( )-cis-ε-viniferin的结构;并纠正了文献核磁共振氢谱(^1H-NMR)数据。  相似文献   
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INTRODUCTION BY THE COLUMN EDITORS: Because the mental health system in Japan has emphasized hospital-based treatment (1), patients with schizophrenia often remain institutionalized for long periods, even after their symptoms have stabilized. In addition, the introduction of modern community-based methods of treatment and rehabilitation was delayed by an antipsychiatry movement in the 1970s and the ascendance of a reductionistic biological approach to services (2). Lack of adequate outpatient services and community residential care in Japan has been a serious obstacle to destigmatization of mental disorders and has contributed to the heavy burden and stress experienced by families of mentally ill persons (3). More than 80 percent of patients discharged from mental hospitals return to live with their families, who are ill prepared to provide the supportive services required for community tenure.Involvement in work activities can facilitate community reentry for people with serious and persistent mental illness because employment displaces symptoms, provides structure and meaning in daily life, offers socialization with peers, and permits workers to earn income for shelter and food. In this issue's Rehab Rounds column, the authors describe an innovative vocational rehabilitation program for patients with schizophrenia that was designed to overcome obstacles to discharge and community adjustment. The program at Yabuki Prefecture Psychiatric Hospital, in the northern prefecture of Fukushima, Japan, has been successful in training patients for competitive work while capitalizing on the importance of work in Japanese culture and its traditionally supportive employer-employee relationships. The program is termed "hybrid" because it combines elements of transitional employment with supported employment (4).  相似文献   
65.
A hydrophobic, fibrillogenic peptide fragment of human prion protein (PrP106-126) had in vitro toxicity to neurons expressing cellular prion protein (PrP(C)). In this study, we proved that primary cultures of mouse cerebral endothelial cells (MCEC) express PrP(C). Incubation of MCEC with PrP106-126 (25-200 microM) caused a dose-dependent toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase release, bis-benzimide staining for nuclear morphology, and trypan blue exclusion test. Pentosan polysulphate (50-100 microg/ml), a drug effective in scrapie prophylaxis, dose-dependently attenuated the injury. MCEC cultures from mice homogenous for the disrupted PrP gene were resistant to the toxicity of PrP106-126. In conclusion, cerebral endothelium expressing PrP(C) may be directly damaged during spongiform encephalopathies.  相似文献   
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Objective

For patients with end-stage renal disease on hemodialysis, the durability of vascular access (VA) is still far from optimal, and access survival after intervention for access failure is an important aspect. Procoagulant status is a leading cause of access failure. Coagulation-fibrinolysis imbalance can occur in hemodialyzed patients, but the influence of the imbalance has not been fully elucidated.

Methods

We prospectively examined coagulation-fibrinolysis balance to assess the risk of access failure after the intervention of revascularization in a cohort of 462 hemodialysis patients. Thrombin-antithrombin complex (TAT) and plasmin-α2-plasmin inhibitor complex (PIC) are markers for coagulation and fibrinolysis. Median follow-up was 243 days. The end point was clinical access failure: revascularization or access revision. The survival curve for VA patency was assessed using the Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression models that allowed adjustment for baseline differences in age, sex, dialysis vintage, diabetes mellitus, and various factors (quantity of blood flow, prothrombin time-international normalized ratio, fibrin degradation products, C-reactive protein, interleukin-6, tumor necrosis factor-α, and pentraxin-3) were used.

Results

The 162 patients who reached an end point had smaller access flow volume and smaller percentage of arteriovenous fistula and higher TAT/PIC ratio. Kaplan-Meier analysis indicated that the patients with elevated TAT/PIC ratio showed poorer outcome (P < .001). On Cox regression modeling, elevated TAT/PIC was an independent risk factor for access failure (hazard ratio, 1.58; P = .03).

Conclusions

Our results suggest that coagulation-fibrinolysis imbalance is a significant risk factor for access failure and may predict VA failure in hemodialyzed patients after access intervention.  相似文献   
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