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131.
目的观察不同剂量阿托伐他汀对急性冠脉综合征(ACS)患者外周血中总胆固醇(TC)、高敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)、血栓素B2(TXB2)、血小板颗粒膜蛋白-140(GMP-140)、血浆纤溶酶原激活剂抑制物-1(PAI-1)水平及血浆组织型纤溶酶原激活剂(t-PA)活性的影响。探讨阿托伐他汀对ACS防治的可能机制及不同剂量阿托伐他汀的安全性。方法ACS患者65例,在拜阿斯匹林、氯吡格雷等基础治疗外随机分为三组,分别给予阿托伐他汀10mg/d、20mg/d、40mg/d睡前服用。入院第1天、第14天分别抽取空腹静脉血16ml。测定hs-CRP、IL-6、TXB2、GMP-140、t-PA、PAI-1及TC、天冬氨酸转氨酶(AST)、丙氨酸转氨酶(ALT)、肌酸激酶(CK)。采用SPSS13.0统计软件对检测结果的组间及治疗前后进行比较。结果三组TC、hs-CRP、IL-6、TXB2、GMP-140、PAI-1治疗后均有下降、t-PA活性上升,治疗后三组间比较亦有差异;而三组治疗前后CK、ALT、AST组间无显著差异,治疗后无显著上升,以上结果均有统计学意义。结论阿托伐他汀对ACS患者血脂及炎症反应、血小板活性、纤溶活性有积极作用,并在一定范围内随着剂量的增加而加强,同时具有良好的安全性。  相似文献   
132.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, N o 3, pp. 244–245, March, 1993  相似文献   
133.
Aim: Hormone‐sensitive lipase (HSL) has been proposed to regulate triacylglycerol (TG) breakdown in skeletal muscle. In muscles with different fibre type compositions the influence on HSL of two major stimuli causing TG mobilization was studied. Methods: Incubated soleus and extensor digitorum longus (EDL) muscles from 70 g rats were stimulated by adrenaline (5.5 μm , 6 min) or contractions (200 ms tetani, 1 Hz, 1 min) in maximally effective doses or by both adrenaline and contractions. Results: Hormone‐sensitive lipase activity was increased significantly by adrenaline as well as contractions, and the highest activity (P < 0.05) was seen with combined stimulation [Soleus: 0.40 ± 0.03 (SE) m‐unit mg protein?1 (basal), 0.65 ± 0.02 (adrenaline), 0.65 ± 0.03 (contractions), 0.78 ± 0.03 (adrenaline and contractions); EDL: 0.18 ± 0.01, 0.30 ± 0.02, 0.26 ± 0.02, 0.32 ± 0.01]. Glycogen phosphorylase activity was always increased more by adrenaline compared with contractions [Soleus: 60 ± 4 (a/a + b)% vs. 46 ± 3 (P < 0.05); EDL: 60 ± 5 vs. 39 ± 6 (P < 0.05)]. After combined stimulation glycogen phosphorylase activity in soleus [59 ± 3 (a/a + b)%] was identical to and in EDL [45 ± 4 (a/a + b)%] smaller (P < 0.05) than the activity after adrenaline only. Conclusions: In slow‐twitch oxidative as well as in fast‐twitch glycolytic muscle HSL is activated by both adrenaline and contractions. These stimuli are partially additive indicating at least partly different mechanisms of action. Contractions may impair the enhancing effect of adrenaline on glycogen phosphorylase activity in muscle.  相似文献   
134.
Biopsies from the common bile ducts from seven patients undergoing surgery for biliary obstruction due to stones or malignancy were studied histochemically and electron microscopically. The surface of the bile duct is lined by a tall epithelium which extends into diverticula. Apically, they contain some neutral and sialated mucosubstances. Fucosyl residues were found in the Golgi apparatus and along the apical cell membrane. The latter is lined by microvilli. There was a well-developed rough endoplasmic reticulum and Golgi apparatus and a small number of apical secretory droplets. Large numbers of lipid droplets were present basally in some cells. Lipid-containing macrophages were also seen intra-epithelially and in the lamina propria. This suggests a possible pathway for lipid transport. The glands were lined by cuboidal cells, some containing much mucus--sulphated, sialated, and neutral with a basal nucleus. A well-developed endoplasmic reticulum and Golgi apparatus were found with abundant secretory droplets. The glandular epithelium contained lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin. These may play a protective role. The lamina propria contained scattered smooth muscle cells amongst the fibroblasts and inflammatory cells.  相似文献   
135.
There is now considerable evidence suggesting that the plasma membrane of mammalian cells is compartmentalized by functional lipid raft microdomains. These structures are assemblies of specialized lipids and proteins and have been implicated in diverse biological functions. Analysis of their protein content using proteomics and other methods revealed enrichment of signalling proteins, suggesting a role for these domains in intracellular signalling. In T lymphocytes, structure/function experiments and complementary pharmacological studies have shown that raft microdomains control the localization and function of proteins which are components of signalling pathways regulated by the T-cell antigen receptor (TCR). Based on these studies, a model for TCR phosphorylation in lipid rafts is presented. However, despite substantial progress in the field, critical questions remain. For example, it is unclear if membrane rafts represent a homogeneous population and if their structure is modified upon TCR stimulation. In the future, proteomics and the parallel development of complementary analytical methods will undoubtedly contribute in further delineating the role of lipid rafts in signal transduction mechanisms.  相似文献   
136.
目的:探讨Graves’病患者血清瘦素(leptin)与血脂水平变化的临床意义。方法:对29例初诊的Graves’病患者治疗前后及30例健康体检者血清leptin与血脂含量进行测定。结果:29例Graves’病患者治疗前血清leptin、三酰甘油及总胆固醇含量均较对照组明显降低;经治疗T3、T4水平恢复正常后,血清leptin、三酰甘油及总胆固醇含量较治疗前明显升高;与对照组比较差异无显著性。结论:血清leptin与血脂含量的变化可作为判断Graves’病的病情和疗效的指标之一。  相似文献   
137.
138.
139.
Summary Results of comparative studies on stimulation of the rates of cofactor consumption, superoxide generation and hydrogen peroxide production by mitoxantrone (Novantrone®; dihydroxyanthracenedione; MXN), ametantrone (AM), doxorubicin (DOX) and daunorubicin (DNR) in the presence of NADPH-cytochrome P-450 reductase, NADH dehydrogenase, or rabbit hepatic microsomes have been reported. MXN and AM were substantially less effective in stimulating the rate of cofactor oxidation, superoxide formation or hydrogen peroxide production relative to the anthracyclines. In the presence of P-450 reductase, the rate of NADPH oxidation or superoxide generation produced by 100 M MXN or AM was only 15% and 2% respectively of that produced by 100 M anthracycline.The effects of MXN and AM on lipid peroxidation in hepatic microsomes, cardiac sarcosomes and cardiac mitochondria were determined and compared with those produced by ADM. MXN and AM at 50 M inhibited the basal rate of NADPH-dependent rabbit liver microsomal lipid peroxidation by 50%; in contrast, DOX enhanced the rate of hepatic microsomal lipid peroxidation by 2-and 2.5-fold at 100 and 200 M, respectively. Rabbit cardiac sarcosomal NADPH-dependent lipid peroxidation was inhibited completely at 100 M anthracenedione. NADH-dependent lipid peroxidation in cardiac mitochondria was diminished by 50 M MXN and AM, whereas 50 M DOX produced a 2-fold stimulation in lipid peroxidation. The anthracenediones also effectively inhibited DOX-stimulated lipid peroxidation with 50% inhibition occurring at 4 M (MXN) and 6 M (AM). Moreover, both MXN and AM potently inhibited iron (100 M)-stimulated lipid peroxidation in rabbit hepatic microsomes with 80% inhibition produced by 15 M anthracenedione.These results are consistent with the diminished cardiotoxicity of mitoxantrone and ametantrone relative to DOX or DNR and may require a reassessment of the role of lipid peroxidation in the mechanism(s) of quinone antineoplastic agent-mediated cardiotoxicity.  相似文献   
140.
目的 研究人体测量指标对儿童肥胖伴非酒精性脂肪肝的预测作用,探讨不同指标筛查非酒精性脂肪肝的切点值。方法 选取自2018年6月—2019年12月在西安交通大学第二附属医院小儿内分泌门诊就诊的94例肥胖儿童为研究对象,进一步分为肥胖伴非酒精性脂肪肝组与肥胖不伴非酒精性脂肪肝组,52例正常儿童为对照组。测量身高(H)、体重(W)、腰围(WC)、臀围(HC)和血甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C);行肝脏B超的检查。计算体质指数(BMI)、腰臀比(WHR)、腰高比(WHtR)、腹部体积指数(AVI)、脂质蓄积指数(LAP)和内脏脂肪指数(VAI)等指标。通过绘制人体测量指标的受试者工作特征曲线(ROC曲线)评估人体测量指标与肥胖儿童非酒精性脂肪肝的相关性,并比较各项人体测量指标的曲线下面积(AUC)确定切点值。结果 肥胖组BMI、WC、WHR、WHtR、AVI、LAP、VAI及TG均高于对照组(t=23.090、21.068、12.547、22.855、17.578、8.159、5.394、6.183,P<0.001)。肥胖伴非酒精性脂肪肝组BMI、WC、AVI、LAP、VAI均高于肥胖不伴非酒精性脂肪肝组(t=2.180、2.389、2.362、3.643、2.839,P<0.05)。人体测量指标的ROC曲线下面积按从大到小的顺序依次为 LAP、VAI、 WC、 AVI、 BMI。对肥胖伴非酒精性脂肪肝的联合诊断指标进行筛查效能分析结果显示,LAP+AVI 曲线下面积为0.706(95%CI:0.595~0.817,P<0.001);AVI+VAI 曲线下面积为0.685(95%CI:0.570~0.800,P<0.01);BMI+WC 曲线下面积为0.652(95%CI:0.537~0.768,P<0.05)。联合指标的ROC曲线下面积从大到小为LAP+AVI、AVI+VAI、BMI+WC。结论 LAP联合AVI对儿童肥胖伴非酒精性脂肪肝具有较好的筛查作用。  相似文献   
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