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71.
Tarek Sadek Hakim Mazouz Hedi Bahloul Roxana Oprisiu Najeh El Esper Isabelle El Esper Francis Boitte Michel Brazier Philippe Moriniere Albert Fournier 《Nephrology, dialysis, transplantation》2003,18(3):582-588
BACKGROUND: Sevelamer hydrochloride was recently proposed as a phosphate binder to prevent hypercalcaemia in place of calcium alkaline salts in dialysis patients. So far, it has been evaluated only in patients receiving calcitriol, without comparison with CaCO(3) alone, although the latter was found to be as effective as the combination of calcitriol and Al(OH)(3) in suppressing parathyroid hormone (PTH) without inducing hypercalcaemia and to have a better lowering effect on serum phosphate. Moreover, this bile salt binder may decrease serum 25-OH vitamin D. Therefore, we compared for 5 months two strategies for controlling moderate hyperparathyroidism: CaCO(3) alone vs sevelamer in conjunction with measures to increase calcium balance. METHODS: Forty-two patients were randomized: 21 continued their treatment with 4.8 g/day CaCO(3) and 21 were switched to sevelamer (initial dose: 2.4 g/day, increased to 4.4 g/day). Each month, when serum-corrected calcium decreased below 2.30 mmol/l, dialysate calcium was increased or alphacalcidol was given at each dialysis session, according to serum PO(4) levels. The following parameters were monitored: serum Ca, PO(4), bicarbonate and protein, weekly; and serum PTH, 25-OH vitamin D and total, LDL and HDL cholesterol monthly. RESULTS: Except for higher serum phosphate at month 1, lower serum bicarbonate at month 2 and lower LDL cholesterol at month 5 in the sevelamer group, no difference was found between the two groups. Compared with baseline levels, PTH increased and 25-OH vitamin D decreased significantly in both groups, these two parameters being inversely correlated. CONCLUSIONS: Given comparable control of plasma calcium, phosphate and 25-OH vitamin D, PTH control is comparable in both strategies. Sevelamer does not induce greater vitamin D depletion than CaCO(3). The transient decrease of serum bicarbonate after discontinuation of CaCO(3) in the sevelamer group suggests a less optimal prevention of acidosis. The sevelamer-induced decrease in LDL cholesterol gives this drug a potential advantage in cardiovascular prevention. 相似文献
72.
将Wistar大鼠随机分成氧化胆固醇组(Och)、纯胆固醇组(Pch)和对照组,分别用氧化胆固醇混合物(250mg/kg bw/d)、纯胆固醇(250mg/kg bw/d)以及悬浮固醇用的明胶液体给大鼠灌胃,连续二天。于第二次灌胃后18小时,从大鼠尾静脉注射伊文思兰溶液,并于注射后2小时处死;取出主动脉用荧光显微分光光度术测定主动脉内膜的通透性。此外,另一部分动物在第二次灌胃后24小时处死,取出主动脉作扫描电镜的内膜观察。结果表明,Och大鼠主动脉内膜的通透性显著高于Pch组与对照组大鼠(P<0.01),而Pch组大鼠主动脉内膜的通透性和对照组无显著差异(P>0.05)。 相似文献
73.
用Brevibacterium sp.DGCDC-82在7L发酵罐中分批培养.分别对添加剂吐温-80、培养温度、培养基的pH、通风量和搅拌速度在胆固醇氧化酶的生产中的影响进行了研究.结果显示以上条件均对产酶有影响.在不同的发酵阶段改变发酵操作条件,发酵20 h最高酶活可达1203U/L,生产强度可达60 U/(L·h).既有效地提高了胆固醇氧化酶的产量,又防止了发酵过程中的泡沫外溢. 相似文献
74.
Modic changes following lumbar disc herniation 总被引:4,自引:3,他引:1
Only a small proportion (20%) of patients with LBP can be diagnosed based on a patho-anatomical entity. Therefore, the identification
of relevant subgroups, preferably on a patoanatomical basis, is strongly needed. Modic changes have been described by several
authors as being closely linked with LBP. The aims of this study were to describe the prevalence of Modic changes, their development
as well as their association to LBP, previous disc contour, and surgery in patients with previous severe sciatica. This is
a longitudinal cohort study where the patients were recruited from an RCT comparing two active conservative treatments, the
181 patients, who at baseline had radicular pain in or below the knee; all underwent a physical examination and MRI. MRI’s,
pain history and physical examination of 166 patients were obtained at follow-up 14 months later. The prevalence of Modic
changes type 1 increased from 9% at baseline to 29% at follow-up. At that time, a strong association between Modic changes
and non-specific LBP was noted. Apparently, Modic changes type 1 was more strongly associated with non-specific lumbar pain
than Modic changes type 2. The development of new Modic changes was closely related to the level of a previous disc herniation.
A lumbar disc herniation is a strong risk factor for developing Modic changes (especially type 1) during the following year.
Furthermore, Modic changes are strongly associated with LBP. 相似文献
75.
通过平板初筛和摇瓶复筛,从371株菌中筛得一株有工业生产价值的胆固醇酯酶产生菌,并对它进行了发酵条件的研究。用所获得的胆固醇酯酶配制的三酶试剂具有良好的稳定性,适用于临床检测。 相似文献
76.
Abstract. Objectives. To evaluate lipids and lipoproteins as risk factors for coronary heart disease (CHD) in older men with non-insulin-dependent diabetes (NIDDM) or abnormal glucose tolerance compared with normoglycaemic men. Design. A prospective, population-based cohort study based on the lipoprotein examination (1970–72) of the Honolulu Heart Program. Follow-up was through to December 1988. Setting. Honolulu, Hawaii. Subjects. Japanese-American men, ages 51–72 at baseline: 2042 with 1 h glucose < 12.5 mmol l?1 (normal group); 376 on oral hypoglycaemic agents or with 1 h glucose ≥ 12.5 mmol l?1 after 50 g oral glucose challenge (abnormal glucose tolerance group). None had prevalent coronary heart disease (CHD) or stroke at baseline. Main outcome measures. Incident CHD: definite nonfatal myocardial infarction (MI) or fatal CHD. Results. There were 221 incident cases in the normal group, and 65 in the abnormal glucose tolerance group. Total and high-density lipoprotein (HDL) cholesterol were significant predictors of incident CHD in men with NIDDM or abnormal glucose tolerance after controlling for age, body-mass index, systolic blood pressure, pack-years of cigarettes and alcohol consumption (P < 0.05). Total, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterol were significant predictors in normal men, and HDL cholesterol was of borderline significance. Conclusions. Abnormal lipids and lipoproteins are significant, independent predictors of CHD in subjects with NIDDM or abnormal glucose tolerance. Attention to lipid and lipoproteins as CHD risk factors should be part of clinical management of these patients. 相似文献
77.
薄层扫描法测定食物中胆固醇的含量 总被引:1,自引:0,他引:1
本文探讨食物中胆固醇的薄层光密度法的测定。用硅胶G与0.3%CMC-Na按1:2.2比例制成薄层板,石油醚-乙醚--冰醋酸(7:3:0.1)为展开剂,5%磷钼酸乙醇溶液显色,日本岛津CS-910型薄层扫描仪定量扫描,测得精神异系数(RDS%)为2.92。稳定性变异系数(RSD%)为2.35,加嘏率在87.95-94.29%范围内。与气相色谱法(其回收率在92-103%范围)比较,结果相接近,该法简 相似文献
78.
L. J. Dowie J. E. Smith A. J. MacGilchrist R. Fraser J. W. Honour J. L. Reid C. J. Kenyon 《European journal of clinical pharmacology》1988,35(6):625-629
Summary The site of omeprazole inhibition of adrenal steroidogenesis has been sought in vivo by analyzing the patterns of urinary steroid metabolite excretion after 6 days of treatment with placebo/omeprazole.Excretion rates of androsterone, aetiocholanolone, dehydroepiandrosterone, 11 hydroxyandrosterone, tetrahydrocortisone, tetrahydrocortisol and cortolone were reduced, indicating a block at an early step in steroidogenesis, possibly cholesterol side-chain cleavage. In vitro studies have confirmed this finding by measuring conversion of added precursors to cortisol in isolated bovine adrenocortical cells. Cortisol synthesis from added 20 hydroxycholesterol was inhibited by 83% in the presence of 100 µg omeprazole/ml. Conversion from pregnenolone and progesterone and their 17 hydroxylated derivatives was inhibited by 20–40% whereas cortisol production from added 11 deoxycortisol was not affected.These data suggest that omeprazole primarily inhibits cholesterol cleavage and does not inhibit 3 hydroxysteroid dehydrogenase, 17 hydroxylase or 11 hydroxylation; 21 hydroxylase activity may be marginally attenuated. 相似文献
79.
背景 随着代谢性疾病发病率的上升,代谢综合征(MS)的预防与控制引起广泛的关注。而脂质比值是重要的筛查指标之一,与MS之间的关系成为热点研究话题。目的 基于贵州省多阶段横断面研究人群分析三酰甘油/高密度脂蛋白胆固醇(TG/HDL-C)、总胆固醇/HDL-C(TC/HDL-C)、低密度脂蛋白胆固醇/HDL-C(LDL-C/HDL-C)及非高密度脂蛋白胆固醇(non-HDL-C)与MS发病风险的关联及预测价值评价。方法 回顾性选取贵州省参与2010年全国疾病监测地区慢性病及危险因素调查、2013年中国慢性病及其危险因素监测、2015年中国成人慢性病与营养监测和2018年中国成人慢性病与营养监测的21 727例自然人群为研究对象,收集研究对象的基线资料,根据是否患有MS将研究对象分为MS组(n=4 981)和非MS组(n=16 746)。绘制受试者工作特征曲线(ROC曲线)分别评价男性和女性TG/HDL-C、TC/HDL-C、LDL-C/HDL-C和non-HDL-C对MS的预测价值。通过Delong检验比较脂质比值预测MS发生的ROC曲线下面积(AUC)的差异。采用多因素Logistic回... 相似文献
80.
The role of dietary factors in patients with type 1 (insulin-dependent) diabetes is reviewed by examining three different aspects: the effect of an acute protein load, the effect of dietary protein restriction on the progression of nephropathy and the metabolic effects of low-protein diets. After an acute protein load some impairment of the renal functional reserve may be observed only in patients with type 1 diabetes and overt nephropathy. However, the renal functional reserve is not able to give useful indications of the extent of renal damage and the prognosis of the disease. Both short-term and long-term dietary protein restriction are followed by a significant decrease in glomerular filtration rate (GFR) and albuminuria in type 1 diabetics with incipient nephropathy. In patients with overt nephropathy the long-term administration of a low-protein diet is followed by significant reductions in the rate of decline of GFR and in urinary protein excretion only when started at GFR values higher than 45 ml/min. The rate of functional deterioration when dietary treatment is prescribed seems critical in modulating the effects of a low-protein diet. In addition, low-protein diets may exert important metabolic and clinical effects beyond their supposed effect on progression. Clearly, an adequate dietary regimen is only part of the medical treatment in patients with diabetic nephropathy. 相似文献