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PURPOSE: To determine whether (D)-penicillamine is effective in reducing hepatic oxalate production and urinary oxalate excretion. MATERIALS AND METHODS: (D)-Penicillamine was administered orally to rats to determine its effect on urinary oxalate excretion and used in isolated rat hepatocytes to investigate the effect of (D)-penicillamine on oxalate production from glycolate. Studies involving hepatic aminotransferases and hepatocytes isolated from (D)-penicillamine treated rats were used to clarify the discrepancy between the in vitro and in vivo results. RESULTS: In hepatocytes (D)-penicillamine lead to a significant reduction in oxalate production from glycolate. In vivo however. (D)-penicillamine led to a significant increase in urinary oxalate excretion and a decrease in plasma aminotransferase activity. Hepatic aminotransferases are involved in diverting oxalate precursors from oxalate production. In vitro, (D)-penicillamine was shown to inhibit hepatic aminotransferases. Hepatocytes isolated from (D)-penicillamine-treated rats produced significantly more oxalate than controls. CONCLUSIONS: These results indicate that (D)-penicillamine increases hepatic oxalate production and urinary oxalate excretion. (D)-penicillamine therefore has no therapeutic potential for reducing endogenous oxalate production and urinary oxalate excretion. Moreover, in conditions such as Wilson's Disease which is often associated with hypercalcuria, its use may be contraindicated. 相似文献
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DE Anderson G St-Jean DC Richardson RM DeBowes JK Roush SR Lowry PW Toll HM Aberman DC Van Sickle JJ Hoskinson 《Canadian Metallurgical Quarterly》1997,68(6):571-576
The analysis of health state of drivers sent for an extra health examination for the estimation of driving capability for the driving of motor vehicle in alcoholic state was presented. The study included 380 drivers who were found driving drunk by traffic police (studied group) and 180 drivers of control group sent for an extra health examination for some other reason. The disorders in psychomotor sphere were noticed in the drivers of studied group and it was determined that they had caused significantly larger number of traffic accidents in last five-year period compared to the drivers of control group. The alcohol consumption in driving population represents significant medical, social, economic and traffic problem. The control of driver's alcoholism, the sending of alcoholic drivers to an extra health examination for the repeated estimation of driving capability and including in therapeutic and health-educational program can present significant measure of the primary prevention of road traffic traumatism which is on the constant increase. 相似文献
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JB Kotch DC Browne CL Ringwalt V Dufort E Ruina PW Stewart JW Jung 《Canadian Metallurgical Quarterly》1997,21(11):1025-1037
OBJECTIVE: The purpose of this research was to determine whether risk factors for a maltreatment report in the first year of life, especially the interaction of life event stress and social support, persist into the second and third years of life. METHOD: Predominantly low income mothers who had been interviewed shortly after the birth of infants in a longitudinal cohort were re-interviewed around the infants' first birthdays, and reports to North Carolina's Central Registry of Child Abuse and Neglect were tracked for substantiated maltreatment reports. RESULTS: Variables significantly associated with a substantiated maltreatment report in the second or third year of life (p < .01) were first year maltreatment reports and participation in Medicaid. Three interactions between a stressful life event indicator variable and a social support indicator variable were significant predictors of substantiated second or third year reports (p < .05). CONCLUSIONS: Even in the presence of significant risk factors from the first year of life, life event stress can increase the risk of a substantiated maltreatment report in the second or third years of life, but social support may moderate the effect of life events. 相似文献
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BACKGROUND: The danger of coronary reoperations is mainly hidden in the reopening of the sternum and in the manipulation of the heart and the old grafts. Therefore, the minimally invasive direct coronary artery bypass procedure seems an ideal technique for coronary reoperations if only the left anterior descending coronary artery needs to be revascularized and the left internal mammary artery has not been used previously. METHOD: From January 1995 until May 1996 we performed 81 minimally invasive direct coronary artery bypass procedures through a small anterolateral thoracotomy in the fifth intercostal space, anastomosing the left internal mammary artery to the left anterior descending coronary artery. Six of these 81 were reoperative minimally invasive direct coronary artery bypass procedures on patients who had previously undergone coronary grafting through a median sternotomy with a vein graft to the left anterior descending coronary artery. RESULTS: Mean operation time was 85.8 +/- 22.2 minutes. Mean length of the mammary pedicles was 13 +/- 2 cm. Mean coronary occlusion time was 9.2 +/- 3.2 minutes. Mean postoperative hospital stay was 5.7 +/- 1.2 days (range, 5 to 8 days). No mortality and no cardiac-related morbidity were recorded. CONCLUSIONS: These results suggest that the technique is safe and promising in selected cases of reoperative coronary operation. 相似文献