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91.
LYSOSOMAL IRON ACCUMULATION AND TUBULAR DAMAGE IN RAT PUROMYCIN NEPHROSIS AND AGEING 总被引:1,自引:0,他引:1
David C. H. Harris Ching Tay Brian J. Nankivell 《Clinical and experimental pharmacology & physiology》1994,21(2):73-81
1. Energy dispersive X-ray spectrometry was used to examine the relationship between proteinuria and increased urinary iron excretion, and structural and functional damage in puromycin nephrosis. 2. After 11–12 days rats treated with puromycin (10 mg/100g, i.v.i.) had greater proteinuria (211.6 ± 35.7 mg/day, mean ± s.e.m.) and urinary iron excretion (15.4 ± 2.2 μg/day) than salinetreated controls (14.5 ± 1.4 mg/day and 1.1 ± 0.2 μg/day, respectively, both P<0.001). 3. On day 13, mean lysosomal iron concentration of proximal tubular cells (306.6 ± 64.5 vs 11.9 ± 8.6 mg%, P<0.001), and proximal tubular cell damage assessed semi-quantitively (1.17 ± 0.10 vs 0.62 ± 0.10, P<0.001) were higher and creatinine clearance (0.15 ± 0.01 vs 0.29 ± 0.02 mL/min perg kidney weight, P<0.001) lower than in control rats. 4. At days 35, 60 and 360 there were no differences in any of the measured parameters between rats treated with puromycin or saline, and in both groups proteinuria, tissue damage and lysosomal iron concentration increased with time. 5. Lysosomal iron accumulation was the only independent predictor of both functional and structural damage. 6. In conclusion, the apparent association between proteinuria and tubulo-interstitial damage in puromycin nephrosis, and with ageing, is best explained by factors associated with accumulation of iron within lysosomes of proximal tubule cells. 相似文献
92.
汽车驾驶员心电多相频谱分析 总被引:2,自引:0,他引:2
对117例汽车司机应用HBD-1心电多信息诊断仪进行心电多相频谱分析,其功率谱,传递相移,幅度直方图等五项指标总分阳性率明显高于对照组,随着驾车年限的增加,总分阳性率有升高趋势,心电频谱分析对230例冠心病病人阳性检出率84.78%。研究认为汽车司机是易发高血压,冠心病的危险人群,该方法在冠心病的环境流行病学研究中具有重要的临床,亚临床意义。 相似文献
93.
E M Mathus-Vliegen K van de Voorde A M Kok A M Res 《Journal of internal medicine》1992,232(2):119-127
Dexenfluramine, an effective and safe serotoninergic drug with anorectic and possible food-selection-tuning properties, was investigated in a placebo-controlled study of 1 year's duration in severe and refractory obesity. The aim of the study was to assess weight loss, and changes in cardiovascular risk factors, food intake and eating behaviour. Dexfenfluramine- and placebo-treated patients achieved a similar weight loss (greater than 10% of initial weight, by 39.5 and 30.0%, greater than 20% of initial overweight by 42.1% and 32.5% and greater than 10 kg by 41.4 and 33.3%, respectively, of the initial cohorts). Furthermore, the decreases in weight (10.7 vs. 8.0 kg), in body mass index (3.9 vs. 2.9 kg m2) and in waist/hip ratio (0.04 vs. 0.02) were not significantly different. After discontinuation of the drug, the increase in weight (2.8 vs. 1.0 kg) was significantly higher in the dexfenfluramine-treated group. Except for a borderline better effect on glucose of dexfenfluramine, both groups showed similar beneficial changes in food intake and cardiovascular risk factors. Eating behaviour in response to emotional and external stimuli was comparable in the two groups, but placebo-treated patients had to restrain their eating more in order to achieve the same weight loss. Notwithstanding the fact that weight losses and an associated amelioration of health-risk factors were of similar magnitude in dexfenfluramine- and placebo-treated patients, dexfenfluramine might have a useful role in promoting a less stressed adherence to prolonged restriction of energy intake in the severe and refractory obese subject. 相似文献
94.
Marc Ziegler Alexandre Castro-Caldas Susanna Del Signore Olivier Rascol 《Movement disorders》2003,18(4):418-425
Piribedil is a non-ergot D2/D3 agonist with a significant antagonist action on alpha2A and alpha2C adrenergic receptor subtypes. This double-blind placebo-controlled study was undertaken to confirm the efficacy of 150 mg/day piribedil po in improving motor symptoms of idiopathic Parkinson's disease (PD) in nonfluctuating patients insufficiently controlled by a stable daily dose of levodopa (L-dopa). Efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) III score as primary criterion over 4 months. A second comparison was planned at 6 months, after possible adjustment of L-dopa. At 4 months, the rate of response, defined as a 30% decrease from baseline on UPDRS III score, was significantly greater with piribedil compared with placebo (56.4% vs. 37.7%; P = 0.040). At 6 months, the better efficacy of piribedil was maintained (61.8% of responders vs. 39.6% on placebo; P = 0.020). The difference between groups on UPDRS III change from baseline reached statistical significance only at 6 months: -10.0 points in the piribedil group vs. -6.7 points in the placebo group (P = 0.037). Secondary end-points were not significantly different. The most frequently reported adverse events were gastrointestinal symptoms (27 of 61 patients in the piribedil group vs. 13 of 54 patients in the placebo group). In conclusion, a 6-month oral administration of 150 mg/day piribedil in combination with L-dopa is well tolerated, except for minor gastrointestinal symptoms at the beginning of the treatment and significantly improves motor symptoms compared with placebo in PD nonfluctuating patients. 相似文献
95.
Amy J Bastian Valerie E Kelly Fredy J Revilla Joel S Perlmutter Jonathan W Mink 《Movement disorders》2003,18(9):1000-1007
The purpose of this study was to determine the effects of unilateral versus bilateral subthalamic nucleus (STN) stimulation on quantitative measures of walking and reaching in Parkinson's disease (PD). We used kinematic measures and the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale (subscale III) to evaluate the movement of 6 people with PD who had bilateral STN stimulators implanted for at least 6 months and withheld their anti-parkinson medication for at least 8 hours. Subjects were studied with both stimulators off, one on, and both on. Kinematic data were collected as subjects walked, reached to a target, and were rated using the UPDRS motor subscale. STN stimulation improved walking speed and stride length, with the greatest benefit from bilateral stimulation. Reaching speed was improved by unilateral STN stimulation alone, with no additive effect of bilateral stimulation. UPDRS motor subscale ratings paralleled the kinematic findings. STN stimulation did not restore PD subjects' movements to the level of age-matched controls. Overall, these results provide further evidence that the basal ganglia pathways involved in control of walking and reaching may be distinct. We speculate that basal ganglia may influence walking through bilateral pedunculopontine projections and reaching through ipsilateral thalamocortical projections. Our findings also suggest that maximal improvement of walking requires bilateral rather than unilateral STN stimulation. 相似文献
96.
97.
分别采用联合火箭免疫电泳技术和酶法对49例冠心病患者和50例健康人血清载脂蛋白 A_1(apoA_1),载脂蛋白 B_(100)(apoB_(100)),以及血清总胆固醇(TC)、甘油三酯(TG),高密度脂蛋白胆固醇(HDL—ch)的含量进行了测定。结果冠心病患者血清 apoB_(100)(0.99±0.26g/L)明显高于健康人(0.62±0.18g/L);而apoA_1/apoB_(100)比值(1.22±0.35)则明显低于健康人(2.12±0.49);TC,TG,HDL-ch 的含量亦有统计学意义。提示,在预示冠心病危险因素的各种脂类及脂蛋白中,以 apoB_(100)增高 apoA_1/apoB_(100)比值降低最为灵敏,最为准确,且高于单纯测定TC,TG 和 HDL-ch。 相似文献
98.
T. Faillot J. -P. Sichez J. -L. Brault L. Capelle M. Kujas L. Bordi M. Boukobza 《Acta neurochirurgica》1990,105(1-2):44-49
Summary The authors report the third published case of a Lhermitte-Duclos disease diagnosed preoperatively with the help of MRI, stressing its possible extension beyond the limits of the posterior fossa. The pertinent literature is reviewed concerning the clinical and radiological picture of this disease, as well as the different pathogenic hypothesis. 相似文献
99.
The progressive degeneration of the brain seen in dementia is often accompanied by behavioural disturbances. Aggressive behaviour is one of the most serious of these disturbances and is a common cause for psychiatric referral, admission to hospital and drug treatment. In this article, we discuss the conceptual issues associated with defining aggressive behaviour in cognitively impaired patients. We then review the aetiology, epidemiology, methods of assessment, and management of aggressive behaviour in elderly people with dementia. 相似文献
100.
P. Praamstra A. R. Cools D. F. Stegeman M. W. I. M. Horstink 《Journal of the neurological sciences》1996,140(1-2):67-74
Movement-related potentials were recorded preceding self-paced voluntary movements in patients with Parkinson's disease and in healthy subjects of the same age group. We compared the Readiness Potential preceding joystick movements in a fixed direction and preceding joystick movements in freely selected directions. In normal subjects the Readiness Potential amplitude was higher preceding freely selected movements than preceding movements in a fixed direction. The Readiness Potential in Parkinson patients failed to be modified by the different modes of movement selection. The modulation of the Readiness Potential by different ways of preparing for movement might be due to the supplementary motor area (SMA) being more strongly engaged by tasks requiring internal control of movements than by tasks that are externally structured. The results suggest that this task-dependent variation of SMA activity is reduced in Parkinson's disease. A failing capacity to adapt SMA activity to different task demands has previously been suggested by evidence from positron emission tomography studies using similar tasks. 相似文献