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41.
目的了解延边地区警察人群的血脂水平。方法将382例(男350例,女32例;朝鲜族165例,汉族217例)延边少数民族自治州公安局职工作为观察组,将100例健康人群作为对照组,应用日立7600生化分析仪分别测定甘油三酯(TG)、总胆固醇(CHO)、高密度脂蛋白胆固醇(HDL—C)、低密度脂蛋白胆固醇(LDL—C),并进行对比分析。结果观察组检出血脂异常者220例,占58.9%;对照组28例,占28%,两者差异有统计学意义(Х^2=27.78,P〈0.01),观察组明显高于对照组。此外,观察组中朝鲜族与汉族的血脂异常率差异无统计学意义(P〉0.05),但男女差异显著(P〈0.01)。结论延边地区警察人群的血脂代谢异常率明显高于普通人群,无民族差异,提示该人群应及早加强健康教育和其他预防措施。  相似文献   
42.
Low density lipoprotein (LDL) has been found to represent a suitable carrier for cytotoxic drugs that may target them to cancer. This study investigated whether very low density lipoprotein (VLDL), LDL and high density lipoprotein (HDL) can be used to effectively incorporate four cytotoxic drugs, 5-fluorouracil (5-FU), 5-iododeoxyuridine (IUdR), doxorubicin (Dox) and vindesine; characterized the complexes; and examined the effect of incorporation on drug cytotoxicity against HeLa cervical and MCF-7 breast carcinoma cells. Significant drug loading was achieved into all three classes of lipoproteins, consistent with the sizes and hydrophobicity of the drugs. The relative loading efficiency was found to be vindesine>IUdR>Dox>5-FU for all three classes of lipoproteins. As shown by electron microscopy (EM), drug incorporation did not affect the size or morphology of the lipoproteins. Differential scanning calorimetry (DSC) showed that drug loading did not significantly change the thermal transition temperature of core lipids in the lipoproteins. The transition enthalpy was changed only for LDL–Dox and LDL–vindesine. The drugs remained stable in the lipoproteins as determined by high performance liquid chromatography (HPLC). EM, DSC and HPLC data suggest that drugs were incorporated into lipoproteins without disrupting their integrity and drugs remained in their stable forms inside lipoproteins. Compared with free drugs in cytotoxicity assays, the IC50 values of LDL– and HDL–drug complexes were significantly lower (2.4- to 8.6-fold for LDL complexes and 2.5- to 23-fold for HDL complexes). All free or lipoprotein-bound drug formulations were comparably more cytotoxic against MCF-7 than HeLa cells. Upregulating the lipoprotein receptors enhanced, and downregulating them inhibited, the cytotoxicity, indicating the mechanistic involvement of lipoprotein receptor pathways. Complexes of all four drugs with VLDL, in contrast to LDL and HDL, had the same cytotoxicity as the four corresponding free drugs. Our results suggest that further studies are required of the potential of HDL to be a cancer targeting drug carrier.  相似文献   
43.
Objective. To evaluate the impact of chronic inflammation on lipoprotein lipase (LPL) levels and triglyceride metabolism in patients with rheumatoid arthritis (RA). Design. Plasma levels of LPL activity and mass before and after heparin were determined in post-menopausal women with active RA and in controls. The results were related to lipid levels and inflammatory variables. The LPL activity and mass together with triglyceride levels were also measured before and 6 h after an oral fat load. Setting. The study was performed on in- and out-patients at a University Rheumatology clinic. The controls came from the same reference area. Subjects. Altogether 17 consecutive post-menopausal female patients with RA and 16 age and sex matched controls were enrolled for the initial determination of LPL. Fifteen of the patients and 15 of the controls agreed to take part in the fat load. Of these, one patient and one control were excluded. Main outcome measures. LPL determination: basal levels and post-heparin levels of LPL activity and mass. Correlations between LPL and blood lipids (cholesterol, triglycerides), lipoprotein levels (high density lipoprotein, HDL; low density lipoprotein, LDL), erythrocyte sedimentation rate (ESR) acute phase proteins (orosomucoid, haptoglobin, fibrinogen mass) and cytokines (tumour necrosis factor α, TNF-α; interleukin 1β, IL-1β; and interleukin-6, IL-6). Fat tolerance test: LPL activity, mass and triglyceride levels before and 6 h after a per oral fat load. Results. Pre-heparin LPL mass (P<0.01) and activity (P<0.01) were significantly lower in the rheumatoid patients. Pre-heparin LPL mass showed no correlation to the lipid levels, but an inverse correlation to several inflammatory parameters; it was significant for orosomucoid (rs=?0.63, P<0.05) and C-reactive protein (CRP) (rs=?0.54, P<0.05) and close to significant for haptoglobin (rs=?0.48, P=0.087) and IL-6 (rs=?0.52, P=0.061). Six hours after a lipid load the LPL activity and mass were significantly lower in RA (P<0.05 and P<0.01, respectively) but the triglyceride level was not significantly different compared to controls. Conclusion. An inverse relationship exists between inflammatory status and pre-heparin LPL mass. Pre-heparin LPL mass reflects mainly the inactive monomeric fraction of LPL. This has been shown to hinder the uptake of remnant lipoprotein particles through competition with lipoprotein bound dimeric LPL for the LDL receptor-related protein (LRP receptor) on hepatocytes and macrophages in culture. A decrease of the level of monomeric LPL in plasma may thus be beneficial for remnant catabolism. The same mechanism may on the other hand increase macrophage uptake of lipids. This may not affect global lipid metabolism but may be important in driving the atherosclerotic process in the vessel wall.  相似文献   
44.
本文报导了1983~1984年北京市城区(宣武区),近郊区(西红门)和远郊区(大皮营)母乳脂质成分的测定结果,并结合乳母营养状况给予评价。 共测定了207例母乳比重,平均范围在1.018~1.023之间;测定了216例母乳的脂肪含量(g/100g乳),城区平均值为3.78,近郊区为3.31,远郊区为3.08,城区的显著较高;测定了194例母乳胆固醇含量,初乳的最高(23.4mg/100g乳),以后逐渐减低,到第三个月后达稳定水平(约10mg/100g乳),三个调查点的情况相同,测定了221例母乳的脂肪酸组成,其主要成分为油酸(29~37%),棕榈酸(17~25%)和亚油酸(12~25%),远郊区母乳中所含的必需脂肪酸显著较高。 统计分析证明三个地区的乳脂含量(%)与乳胆固醇含量(mg/100g乳)间有显著性相关(P<0.01);188例乳母的膳食脂肪摄入量(g/日或%kcal)与乳脂含量间也有显著性相关(P<0.05),此结果表明,北京城乡母乳的乳脂含量可能受膳食脂质与量的影响,其脂肪酸组成的特点是亚油酸含量高,反映了我国人民以素食为主的饮食习惯。乳中的必需脂肪酸供给量可满足婴儿所需,胆固醇供给量为70~85mg/d,可作为同龄婴儿自母乳摄入量的参考。  相似文献   
45.
Consecutive survivors of a myocardial infarction from the Southern Hospital, below 70 years of age, were randomized into a Control group (n=276) and a Treatment group (n=279). The latter was openly prescribed the combination of clofibrate and nicotinic acid for serum lipid lowering. Each patient should remain in the study for 5 years and be seen regularly every 4 months at a special IHD outpatient clinic within the hospital. The concentration of serum cholesterol and triglyceride was lowered by 13% and 19%, respectively, in the Treatment group compared to the Control group. Total mortality was 82 cases in the Control group and 61 in the Treatment group, a 26% reduction (p<0.05). For patients above 60 years of age in the Treatment group the reduction in mortality was 28% (p<0.05). IHD mortality was reduced by 36% (p<0.01)in the Treatment group compared to the Control group. The beneficial effect of the serum lipid lowering treatment was related to the serum triglyceride concentration in two ways. First, it only occurred in patients with a triglyceride level >1.5 mmol/l (n=216). Secondly, it was most pronounced in the 44% of the treated patients who had a lowering of the serum triglyceride concentration by 30% or more, and in this subgroup the reduction of IHD mortality was 60% (p<0.01). For serum cholesterol there were no such relations. The difference between serum triglycerides and cholesterol concerning these relations to the treatment outcome may be due to the fact that hypertriglyceridaemia was the most common hyperlipidaemia among our patients, occurring in 50%, while hypercholesterolaemia only occurred in 13 %. Caution should be exercised in the interpretation of the results as the trial was not blind. However, the fact that the decrease in IHD deaths was directly related to the degree of serum triglyceride lowering indicates that it was the drug effect on serum lipids that was reponsible for the beneficial effect of the treatment.  相似文献   
46.
Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2–10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the acqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.Abbreviations HMG-CoA hydroxy-methylglutarylcoenzyme A - 4S Scandinavian Simvastatin Survival Study - LOM lens opacity meter  相似文献   
47.
BACKGROUND: Atherosclerosis begins early in life. Infections might contribute to the pathogenesis of atherosclerosis. In this study, we investigated whether acute infections in children could alter the carotid wall morphology and the lipid profile. METHODS: Mean carotid intima-media thickness (IMT) was measured by high-resolution ultrasound in 28 hospitalised children (mean age: 5+/-2 years), who fulfilled the diagnostic criteria of acute infections (body temperature, >38 degrees C; C-reactive protein, >15mg/ml, and clinical), and in 20 age- and gender-matched controls. Antibodies against oxidised low-density lipoprotein (anti-oxLDL antibodies), as well as total and high-density lipoprotein cholesterol (HDL-C) were analysed in all children. The infection group was investigated both during the acute illness and 3 months after clinical recovery (post-infection). RESULTS: During the acute illness, the infection group had elevated anti-oxLDL antibodies and decreased HDL-C, as compared to those obtained at 3 months and in controls (p<0.05). These changes in the infection group were followed, at 3 months, by thickening of carotid intima-media. Those who received antibiotics during their acute illness had less carotid thickening than those who were not treated with antibiotics (p<0.05). CONCLUSION: Acute infections in children seem to be accompanied by enhanced oxidative modification of LDL and by decrease in HDL-C. These lipid changes may be followed by thickening of carotid artery intima-media. These findings suggest that, in childhood, acute infections could be associated with increased risk of atherosclerosis, and warrant further studies on this topic.  相似文献   
48.
张曹进  陈富荣 《循证医学》2006,6(3):143-146
4 背景 强化降脂使低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)低于指南推荐的水平将使急性冠脉综合征患者获益。但强化降脂使稳定性冠心病患者的LDL-C低于100mg/dL是否安全和有效尚不清楚。  相似文献   
49.
Objective To determine the concentrations of cholesterol sulfate ( CS) in human sera and pla-cental villi during the course of pregnancy. And to analyze its inhibitory activity on thrombin and further characterize the functional significance of CS. Methods The concentrations of CS were determined by thin-layer chromatog-raphy (TLC) on 60 cases of normal pregnant women and 30 cases of normal placental villi. The effect of CS in human sera on the activity of thrombin was analyzed. Results The concentrations of CS in human sera gradually increased from the first to third trimester of gestation with a correlation coefficient of 0. 69, and a correlation between the concentration of CS and weeks of gestation (P <0. 01). CS was also contained in the placental villi, and its concentrations at the second and third trimester of gestations were 4. 7 and 6. 2-fold of that at the first trimester of gestation. CS inhibited the activity of thrombin. Conclusion Placental CS is one of the sources of CS in the serum , pr  相似文献   
50.
BACKGROUND: The increase in allergic diseases is still unexplained. It was hypothesized that the intake of unsaturated fatty acids is a contributing cause of this development. We investigated the relationship between serum cholesterol levels, intake of polyunsaturated fatty acids (PUFA) and manifestations of atopy in a population-based setting. METHODS: A nested case-control study was performed within the population of the 3rd MONICA survey in Augsburg (Germany). The serum levels of total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol of 1537 adults (aged 28-78 years, response 61.4%) and the estimated intake of PUFA in a subset of 139 men were compared with the frequency of a doctor's diagnosis of asthma, allergic rhinoconjunctivitis (AR), atopic eczema (AE) and allergic sensitization as measured by skin prick and Radio Allergo Sorbent Test. FINDINGS: In bivariate analyses, we obtained a negative linear association between total and LDL cholesterol levels and the frequency of AR and sensitization, which was no longer significant after adjustment for important confounders. In contrast, positive linear associations were found between HDL cholesterol levels and AR and AE and, furthermore, between the intake of PUFA and allergic sensitization in men (P<0.01). After adjustment, an increasing risk for atopic diseases with increasing levels of HDL cholesterol and an increasing risk for allergic sensitization with increasing intakes of PUFA remained statistically significant. INTERPRETATION: There is indication that HDL cholesterol also plays a role in the complex interaction of fat intake, metabolism and the manifestation of atopy in adults. These findings may contribute to the understanding of time trends and regional differences of allergies.  相似文献   
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