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排序方式: 共有1411条查询结果,搜索用时 31 毫秒
11.
Preeclampsia is a pregnancy specific disorder and is thought to be associated with generalized endothelial dysfunction. P-selectin, an adhesion molecule, mediates the interaction of monocytes, platelets, and endothelial cells. Increased P-selectin levels and altered lipid and lipoprotein metabolism were reported in preeclampsia and during pregnancy. In order to investigate the relationship between serum P-selectin and lipoprotein(a), and other lipid parameters, 28 preeclampsia [13 severe (group I) and 15 mild preeclampsia (group II), 15 healthy pregnant (group III) and 20 non-pregnant (group IV)] women were investigated. Serum P-selectin, lipoprotein(a), total cholesterol, triglyceride, and high density lipoprotein cholesterol were measured and low-density lipoprotein cholesterol was derived. Serum P-selectin concentrations were consistently and significantly higher in the severe preeclampsia group than in the mild preeclampsia, healthy pregnancy, and non-pregnant control groups (P<0.0001, for all). The mild preeclampsia group also had increased serum P-selectin concentrations compared with the healthy pregnancy group and non-pregnant controls (P<0.05 and P<0.0001, respectively). Serum P-selectin and lipoprotein(a) levels revealed a significant and linear increase with the severity of preeclampsia. There were also significant (in groups I and II) and borderline (in groups III and IV) correlations between P-selectin and total cholesterol. The present study suggests that P-selectin may be an additional risk marker for preeclampsia, and may be useful in distinguishing women with mild and severe preeclampsia and normal pregnancy. Received: 9 November 2001 / Accepted: 6 February 2002  相似文献   
12.
Human hepatic lipase mutations and polymorphisms.   总被引:2,自引:0,他引:2  
Human hepatic lipase (HL) is a 477 residue glycoprotein that hydrolyzes triglycerides from plasma lipoproteins. Familial HL deficiency is a rare recessive disorder that is characterized by premature atherosclerosis and abnormal circulating lipoproteins. While studying the HL gene from the world's index family with HL deficiency, we identified four coding sequence variants of HL, one in each of exons 4, 5, 6, and 8. In this report we present the genetic basis for two new HL gene variants, one in each of exons 3 and 5. All six HL DNA variants are single base pair changes. Two variants (at codons 133 and 202) are diallelic DNA polymorphisms that are silent at the amino acid level. One variant (V73M) is an allele that defines an uncommon HL isoprotein. One variant (N193S) has two alleles of approximately equal frequency in the population that specify two common HL isoproteins. Two variants (S267F and T383M) are rare mutations found to date only in HL deficient subjects and their relatives. Of the six HL variants described to date, only S267F and T383M are associated with hyperlipidemia.  相似文献   
13.
Lennart  Iselius 《Clinical genetics》1979,15(4):300-306
A path analysis of published reports on family resemblance reveals an important role for genetic factors in all lipids and lipoproteins, with no evidence of a discrepancy between twins and other relatives (which might be due to dominance or epistasis) nor between studies which used environmental indices and those which did not. Family environment within population is less important and is significantly greater for twins than for other relatives.  相似文献   
14.
Pancreatic lipase (EC 3.1.1.3) is an exocrine secretion that hydrolyzes dietary triglycerides in the small intestine. We developed genomic amplification primers to sequence the 13 exons of PNLIP, which encodes pancreatic lipase, in order to screen for possible mutations in cell lines of four children with pancreatic lipase deficiency (OMIM 246600). We found no missense or nonsense mutations in these samples, but we found three silent single-nucleotide polymorphisms (SNPs), namely, 96A/C in exon 3, 486C/T in exon 6, and 1359C/T in exon 13. In 50 normolipidemic Caucasians, the PNLIP 96C and 486T alleles had frequencies of 0.083 and 0.150, respectively. The PNLIP 1359T allele was absent from Caucasian, Chinese, South Asian, and North American aboriginal samples, but had a frequency of 0.085 in an African sample, suggesting that it is a population-specific variant. In an association analysis of 185 African neonates, the PNLIP 1359C/T SNP genotype was significantly associated with concentrations of plasma lipoproteins. These associations were most likely due to linkage disequilibrium with another functional variant at or near PNLIP. Thus, we report three new SNPs for the PNLIP, which may serve as markers for association analyses and for pharmacogenetic studies of pancreatic lipase inhibitors. Received: January 18, 2001 / Accepted: February 19, 2001  相似文献   
15.
The objective of this study was to examine the relationship between lipid peroxidation and aging in the male housefly. Metabolic rate of flies is known to be higher and life span shorter at elevated ambient temperature. Evolution of n-pentane and level of thiobarbituric acid (TBA) reactive material were used as indicators of lipid peroxidation. n-Pentane accumulated by houseflies in vivo and by whole body homogenates of houseflies, in response to tert-butyl hydroperoxide (1 mM), increased with age. n-Pentane accumulation in vivo was markedly higher at higher ambient temperature. Furthermore, n-pentane generated by flies in vivo and by fly homogenates in vitro tended to be lower in flies raised at a lower ambient temperature. TBA-reactive material, elicited by tert-butyl hydroperoxide, was augmented in older flies, but no significant difference was found between flies aged at different ambient temperatures. Analysis of fatty acids in housefly homogenates indicated an age-associated increase in the ratio of polyunsaturated to saturated fatty acids.  相似文献   
16.
以21例Ⅱ期高血压患者、21例Ⅱ期高血压病高胰岛素血症患者及20例正常人为研究对象,以全血比粘度、全血还原比粘度、血浆比粘度、红细胞压积及血浆甘油三酯、总胆固醇、高密度脂蛋白为指标;结果表明Ⅱ期高血压病患者全血比粘度、全血还原比粘度较正常人高,Ⅱ期高血压病高胰岛素血症患者亦较单纯高血压病患者进一步增高,同时其血浆甘油三酯较单纯高血压病患者增高,高密度脂蛋白降低.而血浆比粘度、红细胞压积、总胆固醇三组间无显著性差异。单纯高血压病患者与正常人组比较血脂无差异。因而认为高血压病患者的高胰岛素血症可使高血压病患者增高的血粘度进一步增高,且血粘度的增高主要是红细胞机能、代谢的改变所致。单纯高血压病患者血脂改变不明显,高血压病患者血脂的改变主要是由高胰岛素血症所致。  相似文献   
17.
Summary Rats have been fed diets containing 24.2% coconut or corn oil or an equal mixture of each for 14–18 weeks. Half of the animals in each dietary group were exercised by running in motor-driven work wheels throughout the entire experimental period. During the final 10–14 weeks, these exercised animals ran continuously for 60 min at 1.0 mph or faster each day. Comparisons between sedentary groups revealed that hepatic cholesterol and excretion of digitonin precipitated sterols in the feces increased (P < 0.01) as the per cent of unsaturated fat (corn oil) in the ingested food increased. In contrast, total liver lipid decreased (P < 0.01) as the consumption of corn oil increased. No change in plasma cholesterol occurred in the sedentary rats in response to the three diets. Hepatic cholesterol of the exercised groups was significantly less (P < 0.05–P < 0.01) than that of their respective control groups (same diet). However, the group fed the corn oil diet had a significantly higher (P < 0.01) liver cholesterol after exercise than did the exercised group fed the coconut oil diet. Liver lipid was reduced (P < 0.01) by exercise in the corn oil and mixed corn-coconut oil fed groups. Plasma cholesterol and sterol excretion were unchanged by the exercise program.This investigation supported by Research Grant HE 08262 from the National Heart Institute, National Institutes of Health, U.S. Public Health Service.  相似文献   
18.
Objective: To determine the effects of tibolone, a synthetic steroid used to alleviate climacteric symptoms and prevent osteoporosis, on lipoprotein metabolism, with particular reference to lipoprotein(a) levels and HDL subfraction profiles.Design: Thirty nine postmenopausal women were treated with tibolone (Livial) 2.5 mg/day for 6 months and fasting serum lipoprotein levels were estimated at 0, 2, 4 and 6 months. Results: Lipoprotein(a) levels were reduced significantly over the 6 months from a median level of 245 (range <60–780) mg/I to 152 (range <60–530) mg/l, a reduction of 39% in the median level. A decrease was observed in approximately two thirds of the women. Reductions were noted in all 6 subjects whose pretreatment levels were high, although concentrations remained at a level associated with increased risk in all but one. There were significant decreases in triglycerides and VLDL cholesterol and no significant change in LDL cholesterol. There was a significant reduction of 18% in HDL cholesterol and a 26% reduction in the HDL2:HDL3 ratio. Conclusion: The reduction in lipoprotein(a) levels may have a beneficial effect on cardiovascular risk, which could go some way towards balancing the potentially adverse effect on the cardiovascular system caused by the reduction in HDL cholesterol.  相似文献   
19.
目的:研究老年单纯收缩期高血压(ISH)患者血浆同型半胱氨酸(Hcy)与胆固醇(Tc),甘油三脂(Tg)水平的变化及其相关性。方法:运用高效液相色谱仪及氧化酶法分别测定35例ISH患者,31例单纯期高血压患者,34例原发性高血压患者及30例健康对照组血浆Hcy,Tc,Tg水平,结果:(1)单纯收缩期高血压患者,舒张期高血压患者,原发性高血压患者的Tc,Tg水平均高于健康对照组,差异有显著性意义(P<0.01),而Hcy水平只有单纯收缩期高血压和原发性高血压患者高于健康对照组,差异有显著性意义(P<0.01);舒张期高血压患者的Hcy水平与健康对照组相比无显著性差异(P>0.05),(2)单纯收缩期高血压患者的Tc,Tg水平与舒张期高血压患者,原发性高血压患者的Tc,Tg水平相比没有显著性差异(P>0.05),但单纯收缩期高血压患者和原发性高血压患者,原Hcy水平却高于舒张期高血压患者,差异有显著性意义(P<0.01),(3)Hcy与Tc,Tg均呈正相关,相关系数分别为0.355(P<0.01),0.389(P<0.01)。结论:老年ISH患者和原发性高血压患者血浆Hcy水平较舒张期高血压患者和健康正常对照组均明显增高,且血浆Hcy和Tc,Tg间有一定的相关性。  相似文献   
20.
梯度胶电泳法测定冠心病患者血浆小密低密度脂蛋白   总被引:1,自引:0,他引:1  
目的 建立实用的小密低密度脂蛋白(sdLDL)测定方法, 观察冠心病患者血浆中sdLDL和脂类成分的变化及相互关系。方法 采用2%~16%非变性聚丙烯酰胺梯度胶电泳和凝胶成象分析系统, 测定了105名冠心病患者和90名健康对照者血浆sdLDL、 血脂。结果 sdLDL>50%的检出率, 冠心病组为38.1%, 对照组为11.1%(P<0.01);sdLDL增多患者的甘油三酯水平(2.43±1.22) mmol/L明显高于sdLDL正常者(1.46±0.64) mmol/L, P<0.01。结论 sdLDL与冠心病发生发展有关, 且与甘油三酯关系密切;sdLDL测定可作为预测冠心病危险性的指标之一。  相似文献   
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