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1.
载药脂质超声微泡造影剂的制备及应用研究   总被引:14,自引:1,他引:13       下载免费PDF全文
载药脂质微泡是近年来国内外研究的热点之一,目前已制备出微米级及纳米级载药脂质微泡,本文就载药脂质超声微泡造影剂的特点、制备、应用、现存的问题及发展前景做一综述。  相似文献
2.
瘦素、胆囊收缩素、血脂与胆石类型关系探讨   总被引:5,自引:0,他引:5  
目的探讨瘦素(leptin)、缩胆囊肽(CCK)、血脂、胆固醇与Gs和HS两类胆石病关系。方法比较检测339例胆囊结石(Gs),67例肝胆管结石(HS)病员,20例正常对照者血清leptin、CCK、胰岛素、肝功能、血脂、脂蛋白等,评价各检测指标间关系。结果GS组leptin、CCK、BMI、胆固醇、甘油三酯、白蛋白、GGT、APO-a显著高于HS组(P〈0.05);GS组内leptin与CCK、BMI、胰岛素、转氨酶、胆红素、胆固醇呈正相关(P〈0.05);HS组内leptin与CCK、BMI、胰岛素、转氨酶、胆红素呈正相关(P〈0.01),与白蛋白、APO-a呈负相关(P〈0.05)。结论Leptin参与调控脂质代谢,两类胆石Leptin、血脂等存在明显差别,从调控脂质代谢角度探讨Leptin在两类胆石中的作用可能对阐明胆石成因具有价值。  相似文献
3.
不同脂肪乳剂对肝移植大鼠脂代谢及氮平衡的影响   总被引:5,自引:0,他引:5  
目的研究含不同脂肪乳剂(fatemulsion,FE)的肠外营养(parenteralnutrition,PN)对肝移植大鼠脂代谢及氮平衡影响。方法建立肝移植大鼠模型,随机分为葡萄糖组(GLU组,不使用FE)、结构脂肪乳剂组(STG组)、长链脂肪乳剂组(LCT组)、中长链脂肪乳剂组(MCT/LCT组)4组,于术后6h开始给予单糖或单糖与不同类型FE联合供能的PN,同时设立假手术对照组(SO组)。于PN后1、4、7d收集标本,检测氮平衡、血脂、肝组织脂类的变化。结果与3种脂肪乳剂组相比,GLU组7d内TG和LDL-C逐渐升高,HDL-C持续降低,7d时呈负氮平衡,7d动物死亡率为50%。7d内3种脂肪乳剂组血清TG、TC、LDL-C恢复正常水平,与SO组比较差异无统计学意义;HDL-C水平持续升高,7d内均达到正氮平衡;3种脂肪乳剂组均无PN所致死亡。4d时STG组先于LCT、MCT/LCT两组转为正氮平衡,7d内STG组氮平衡显著高于LCT、MCT/LCT两组,MCT/LCT组氮平衡高于LCT组。结论单糖PN显著影响受体脂代谢,导致大鼠死亡率增高;单糖不宜作为PN的惟一能源;而含FE的PN不会导致肝脏的脂肪沉积,对受体脂代谢没有明显影响。相反,能改善肝移植受体的氮平衡,有利于动物的长期存活,可用于肝移植后的营养支持。STG的作用优于MCT/LCT和LCT。  相似文献
4.
BACKGROUND: Chronic renal failure (CRF) is associated with an increased risk of ischaemic heart disease (IHD), but the mechanisms responsible are controversial. We investigated the relationship of two sets of candidate mechanisms-indices of LDL oxidation and markers of inflammatory activity-with vascular endothelial dysfunction (VED). METHODS: We carried out cross-sectional analysis of 23 dialysed and 16 non-dialysed CRF patients, 28 healthy controls, and 20 patients with stable angina and normal renal function. The following were determined: (i) LDL oxidation by Cu(2+) and ultraviolet light, serum autoantibodies to oxidized LDL (oxLDL); (ii) forearm flow-mediated vasodilatation, plasma concentrations of adhesion molecules, and von Willebrand factor (vWF); and (iii) circulating levels of TNF-alpha and IL-6, C-reactive protein (CRP), and fibrinogen. RESULTS: Endothelium-dependent vasodilatation (EDV) was lower in angina, pre-dialysis, and dialysis CRF patients than in controls (all P<0.005). Compared with controls, vWf (P<0.005) and adhesion molecules (vCAM-1, P<0.005; iCAM-1, P=0.01; E-selectin, P=0.05) were raised in dialysis, and vCAM-1 (P=0.01) in pre-dialysis CRF patients. Dialysed patients had lower HDL cholesterol (P=0.01) and higher triglyceride (P=0.05) than controls, but LDL-oxidation was similar in all groups. Autoantibodies to oxLDL were raised in angina (P<0.005) and pre-dialysis (P=0.006), but were absent in most dialysed patients. Concentrations of IL-6, TNF-alpha, CRP and fibrinogen were elevated in CRF compared with control and angina patients (P<0.005). In the whole population, IL-6 and TNF-alpha correlated negatively with EDV, HDL cholesterol, and positively with triglyceride, blood pressure, vWf, iCAM-1, vCAM-1 and E-selectin (r=-0.43 to +0.70, all P<0.05). CONCLUSIONS: Endothelial dysfunction is unrelated to LDL oxidation, suggesting that LDL oxidation might not be a major cause of VED in CRF. In contrast VED was more severe in CRF than in angina patients and is associated with increased acute-phase proteins and plasma cytokines, demonstrating a chronic inflammatory state. These observations may explain the VED and increased IHD risk of patients with CRF.  相似文献
5.
Our objective was to evaluate the oxidative stress and renal tubular cell damage in patients who have renal stones compared to normal subjects. The patients were re-evaluated after 1-months supplementation with potassium citrate. We recruited 30 patients (11 males and 19 females) diagnosed with kidney stones and scheduled for surgical stone removal the following month, and 30 healthy non-stone formers (14 males and 16 females). Two 24-h urine samples and one heparinized blood sample were collected from each subject. Plasma was separated from the erythrocytes and assayed for creatinine, potassium, sodium, calcium, magnesium, phosphate, malondialdehyde (MDA, a lipid peroxidation product) (P-MDA), protein thiol as an indicator of protein oxidation, and vitamin E. Erythrocytes were analysed for MDA (E-MDA), reduced glutathione (GSH) and cellular glutathione peroxidase (cGPx) activity. The urine was analyzed for pH, creatinine, potassium, sodium, calcium, magnesium, phosphate, oxalate, citrate, MDA (U-MDA), total protein (U-protein) and N-acetyl--glucosaminidase (NAG) activity. For the stone patients, urine and blood samples were re-evaluated after supplementation with potassium citrate (60 mEq/day) for 1 month. Renal stone patients had higher plasma creatinine and lower plasma potassium, urinary pH, potassium, magnesium, phosphate and citrate than the controls. The patients had higher P-MDA, E-MDA, U-MDA, U-protein and NAG activity, but lower GSH, cGPx activity, protein thiol and vitamin E, when compared with controls. After potassium citrate supplementation, P-MDA and E-MDA decreased while plasma vitamin E, urinary NAG activity and citrate increased. Renal stone disease is associated with high oxidative stress and damage to renal tubular cells. These abnormalities are coincident with an increase in blood lipid peroxidation products and a decrease in antioxidant status. Although supplementation with potassium citrate improved urinary citrate levels and oxidative stress, it neither reduced urinary lipid peroxidation products nor remedied the damage to renal tubular cells, probably due to the existence of kidney stones.  相似文献
6.
Background: Bariatric operations promote weight loss and improve glucose homeostasis. Glucagon-like peptide-1 (GLP-1) is considered as a possible mediator of the antidiabetic effects of such operations. Methods: The present study aimed to gain information on the time course for changes in glucose tolerance, as well as insulin, glucagon and GLP-1 secretion, during an oral glucose tolerance test (OGTT), in 31 obese patients examined 1, 3 and 6 months after Larrad's biliopancreatic diversion (BPD) or 6 months after vertical banded gastroplasty (VBG). Results: A time-related progressive decrease in body weight coincided with lowering of plasma triglycerides, decrease of basal plasma glucose and its incremental area during OGTT, and reduction of basal plasma insulin together with an increase of its incremental area. The time-related decrease of plasma glucagon during OGTT was comparable before and after surgery. Both the basal plasma GLP-1 concentration and its incremental area during the OGTT increased strikingly after surgery, a steady-state situation being reached 3 months after surgery. The most striking differences between the somewhat older and less glucose-tolerant subjects of VBG compared to BPD after surgery, consisted in a decrease in cholesterol and LDL only observed in BPD and a much more pronounced increase in basal and incremental plasma GLP-1 in BPD. GLP-1, like glucagon, increased lipolysis, but failed to duplicate the lipogenetic action of insulin in isolated adipocytes obtained at the time of surgery. Conclusion: These findings support the postulated role of GLP-1, secreted by the hindgut, as a key mediator of the antidiabetic effects of bariatric operations.  相似文献
7.
雌性激素及脂质代谢异常在胆囊结石发病中的作用   总被引:4,自引:0,他引:4  
目的 探讨雌性激素及脂质代谢异常在胆囊结石发病中的作用.方法 测定比较胆囊结石及胆囊息肉患者血清雌激素(E2)和孕激素(P)水平,血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)和载脂蛋白A(APoA1)水平.采用免疫组化检测胆囊组织中雌激素受体(ER)及孕激素受体(PR)的表达.结果 胆囊结石患者血清E2和P水平明显高于胆囊息肉患者,胆囊结石组血清TC、TG、LDL-C水平高于胆囊息肉组,而HDL-C和APOA1水平在两组间差异无统计学意义.胆囊结石患者胆囊组织中ER及PR的阳性率明显高于胆囊息肉组.结论 E2和P通过作用于相应受体.使调控胆囊肌肉收缩的信号分子表达降低,导致胆囊收缩运动受损,胆囊胆汁淤积,同时雌激素可通过对肝脏脂质代谢的影响,使胆汁中胆固醇的饱和度增加,胆汁成石指数提高,可能在促进胆囊结石的形成中具有重要作用.  相似文献
8.
Amino acid and carnitine supplementation in haemodialysed children   总被引:3,自引:3,他引:0  
Plasma carnitine, amino acids and lipids levels were studied in ten uraemic children treated with haemodialysis and given amino acid supplementation with and without carnitine. As carnitine is synthesised from lysine and methionine and has a significant influence on lipid metabolism, the relationship between these was examined. Amino acid supplementation (0.25 g/kg body weight) was started with the intention of improving the plasma amino acid pattern in these children and increasing the concentration of lysine, which is the substrate for carnitine synthesis. Amino acids were administered i. v. during dialysis and carnitine (25 mg/kg body weight i. v.) was administered after dialysis three times a week. Concentrations of most essential amino acids were decreased in these patients. The first period of amino acid supplementation did not increase plasma levels of the essential amino acids, with the exception of tyrosine (P<0.01). After the second period of supplementation, methionine was increased (P<0.01), isoleucine was decreased (P<0.01), but tyrosine normalised and was significantly lower than after the first period (P<0.05). Thus overall amino acid supplementation did not improve amino acid levels; it was inconsistently associated with a further decrease in highdensity lipoprotein-cholesterol and an increase in total protein levels. Lysine concentrations after amino acid supplementation remained low. Paradoxically, before carnitine supplementation a positive correlation between free carnitine and triglycerides was observed. The plasma carnitine concentration, initially very low, was excessively high after carnitine supplementation. After carnitine administration no amelioration of any of the other biochemical indices was observed. Carnitine supplementation was associated with a significant reduction of total protein levels (P<0.01). In children with end-stage renal disease on haemodialysis, neither amino acid nor carnitine supplementation appear to result in significant improvements in plasma levels of essential amino acids or lipids.  相似文献
9.
补肾健骨汤对膝关节病患者氧自由基代谢的影响   总被引:3,自引:3,他引:21  
对58例膝关节病患者用补肾健汤治疗前后的红细胞超氧化物歧化酶及血清脂质过氧化物含量进行了动态检测。结果:患者治疗前SOD活性低于正常,LPO含量高于正常。经治疗病情好转者其氧自由基代谢指标相应改善,显效者恢复正常,无效者仍异常。  相似文献
10.
BACKGROUND: Low-molecular-weight heparin (LMWH) has been suggested as providing safe, efficient, convenient and possibly more cost-effective anticoagulation for haemodialysis (HD) than unfractionated heparin, with fewer side-effects and possible benefits on uraemic dyslipidaemia. METHODS: In this prospective, randomized, cross-over study we compared the safety, clinical efficacy and cost effectiveness of Clexane (enoxaparin sodium; Rh?ne-Poulenc Rorer) with unfractionated heparin in 36 chronic HD patients. They were randomly assigned to either Clexane (1 mg/kg body weight, equivalent to 100 IU) or standard heparin, and followed prospectively for 12 weeks (36 dialyses) before crossing over to the alternate therapy for a further 12 weeks. Heparin anticoagulation was monitored using activated coagulation times. RESULTS: Dialysis with Clexane resulted in less frequent minor fibrin/clot formation in the dialyser and lines than with heparin (P<0.001), but was accompanied by increased frequency of minor haemorrhage between dialyses (P<0.001). Clexane dose reduction (to a mean of 0.69 mg/kg) eliminated excess minor haemorrhage without increasing clotting frequencies. Mean vascular compression times were similar in both groups. Over 24 weeks, no changes in standard serum lipid profiles were observed. CONCLUSIONS: This study suggests that a single-dose protocol of Clexane is an effective and very convenient alternative to sodium heparin, but currently direct costs are about 16% more. We recommend an initial dose of 0.70 mg/kg.  相似文献
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