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81.
16只成年杂种犬复制心肌缺血再灌模型。分为地奥心血康治疗组(DAXXKG)和生理盐水对照组(NSCG)。差速离心分离心肌细胞质膜,无机磷法测定心肌细胞膜Na ̄+,K ̄+-ATP酶活性,荧光法测定心肌细胞膜与血清脂质过氧化物(LPO)含量。结果表明:(1)DAXXKGNa ̄+,K ̄+-ATP酶活性明显高于NSCG(P<0.01);(2)血清LPO含量,随着再灌时间延长,NSCG呈上升趋势,DAXXKG略下降,再灌240min两组比较差异显著(P<0.01);心肌细胞膜LPO含量,DAXXKG低于NSCG(P<0.05);(3)心肌细胞膜Na ̄+,K ̄+-ATP酶活性与LPO含量呈明显负相关(r=-0.83,P<0.01)。这些结果提示DAXXK可通过抗脂质过氧化而实现其保护心肌细胞膜的效应。  相似文献   
82.
The ultrastructure of the skin of four cetacean species, bottlenose dolphin (Tursiops truncatus) long-finned pilot whale (Globicephala melaena), humpback whale (Megaptera novaeangliae), and fin whale (Balaenoptera physalus) was investigated with particular reference to epidermal lipid. It has already been established that massive lipid reservoirs exist in whales, that the biochemical structures of cetacean lipids are unique, and that unusual intracellular lipid droplets appear in the epidermis. We report here some novel findings on scanning electron microscopic morphology of epidermal lipid, and on its ultrastructural morphology in general and specialized integumentary sites, including species not previously investigated. The intracellular epidermal lipid droplets were more extensive than lamellar body-derived intercellular lipid which is within the interstices of stratum externum cells. The intracellular droplets were spherical, highly variable in size ranging from 0.24 m to 3.0 m in diameter, appeared singly or were aggregated in cytoplasmic cavitations, and often were closely associated with epidermal cell nuclei. Evidence for exocytosis of the intracellular droplets was not observed. Significant numbers of intracellular lipid droplets are not observed in the epidermis of terrestrial mammals, so their presence is one of several aquatic specializations of the cetacean integument. Its full significance remains obscure, but it is more probably associated with epidermal cell metabolism than with secretion of lipid.  相似文献   
83.
Restoration of bile flow after 9-day cholestasis in rat liver normalized the content of lipid peroxidation products. The removal of the cholestatic factor after 12-day cholestasis was not followed by recovery of these parameters. We showed that measurement of serum concentration of lipid peroxidation products in patients with cholelithiasis during the preoperative period holds promise for selection of the optimum time for surgical treatment and prediction of the risk of postoperative complications. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 1, pp. 39–42, January, 2008  相似文献   
84.
The objective of these studies was to examine the mechanism by which the specific activity of heart sarcolemma 5'-nucleotidase decreases as function of age. We examined the kinetic properties and the lipid composition of the sarcolemma from animals with different ages. The age groups used were 1 month, 6-8 months and 13-15 months. It was found that the Km of this enzyme increases as the animal develops from 1 month to 6-15 months. The opposite was true with 5'-nucleotidase Vmax. There was no significant difference between the middle age and the older age groups in those parameters. The results of these experiments suggest that the increase in Km in sarcolemma 5'-nucleotidase could be due to the reduction of the sarcolemmal polyunsaturated fatty acid concentration, the only lipid alteration observed.  相似文献   
85.
86.
目的:从能量代谢的角度探讨肠组织与心肌、骨骼肌等肠外组织在失血性休克及复苏后组织损伤的差异性。方法:采用大鼠失血性休克复苏模型,高效液相色谱法测定三磷酸腺苷(ATP)、二磷酸腺苷(ADP)和一磷酸腺苷(AMP)含量;生化及比色法测定黄嘌呤氧化酶(XO)、丙二醛(MDA)和超氧化物歧化酶(SOD)水平。结果:失血性休克后肠组织、心肌和骨骼肌ATP含量明显低于对照组,分别为对照的26.3%、30.7%和62.8%;复苏后,心肌、骨骼肌ATP含量明显高于休克组;失血性休克及复苏后,肠组织XO活化及MDA含量均明显高于对照组,SOD活力则明显低于对照组,其脂质过氧化程度较心肌和骨骼肌严重。结论:失血性休克及复苏后不同组织能量代谢变化及组织损伤程度存在差异性,肠组织能量代谢障碍及损伤程度重于心肌、骨骼肌等肠外组织。  相似文献   
87.
88.
Smoking induces oxidative stress inside the Graafian follicle   总被引:6,自引:0,他引:6  
BACKGROUND: A growing body of evidence indicates that pro-oxidant/antioxidant balance inside ovarian follicles plays an important role in folliculogenesis. Over 20% of women of reproductive age in Europe and the USA regularly smoke cigarettes. The impact of tobacco smoking on the intrafollicular markers of oxidative stress has not been fully elucidated. The objective of the present study was to test the hypothesis that cigarette smoking affects the intrafollicular redox milieu. METHODS: In follicular fluid samples originating from 108 IVF patients, lipid peroxidation was assessed by the thiobarbituric reactive substances method and total antioxidative capacity was quantified by the luminol enhanced chemiluminescence method. The level of patients' exposure to the cigarette smoke was evaluated by measuring the follicular fluid cotinine concentration by means of radioimmunoassay. RESULTS: Intrafollicular exposure to cigarette smoke metabolites was associated with a significant increase in follicular lipid peroxidation intensity (P < 0.001), which was accompanied by a significant decrease in the local antioxidative potential (P = 0.004). CONCLUSION: The results indicate that active smoking affects the pro-oxidant/antioxidant balance inside the pre-ovulatory ovarian follicle by inducing intrafollicular oxidative stress. This provides another possible explanation for impaired folliculogenesis in female smokers.  相似文献   
89.
目的:观察脂质过氧化对培养的人内皮细胞血管细胞粘附分子-1表达的影响。方法:培养的人脐静脉内皮细胞随机分为实验组和对照组。实验组与不同浓度联胺(1μmol/L、5μmol/L、10μmol/L)作用8h, 对照组不加联胺。细胞原位杂交和细胞酶联免疫吸附法分别测定内皮细胞血管细胞粘附分子-1mRNA和蛋白表达。结果:细胞原位杂交结果图像分析表明, 实验组平均吸光度值分别为0.147±0.013、0.292±0.020和0.396±0.022, 是对照组(0.077±0.011)的1.91倍、3.79倍和5.14倍。方差分析表明, 各组间两两比较有显著差异(P<0.01)。细胞酶联免疫吸附测定结果, 实验组平均吸光度值分别是0.158±0.008、0.220±0.017和0.321±0.023, 为对照组(0.104±0.016)的1.53倍、2.12倍和3.09倍。各组间两两比较有显著差异(P<0.01)。结论:人脐静脉内皮细胞脂质过氧化增加血管细胞粘附分子-1mRNA和蛋白表达, 这可能促进单核细胞粘附血管内皮, 在动脉粥样硬化发生发展中起重要作用。  相似文献   
90.
Lateral association of sphingolipids and cholesterol is considered to form membrane microdomains such as “lipid rafts” obtainable as a detergent-resistant membrane microdomain (DRM) fraction after solubilization with a non-ionic detergent and density gradient centrifugation. Since not only sphinogolipids and cholesterol, but also functional lipids such as phosphatidylinositol 4,5-bisphosphate (PIP2) are reported to be localized in DRM prepared from several cultured cells, this domain is considered to be a platform mediating lipid-signaling. Although PIP2 is considered to have pivotal roles in the nervous system, little information is available on the localization of PIP2 in the DRM within the synaptic plasma membrane (SPM) obtained from matured rat brains. In this study, in order to know the localization of PIP2 in SPM-derived DRM, we measured the amount of PIP2 in SPM and SPM-derived DRM, by the thin-layer chromatography blotting method, using a GST-fusion protein of the pleckstrin-homology domain of phospholipase Cδ1 as a PIP2 binding probe. About 10% of the PIP2 in SPM was recovered in DRM. In contrast, over 40% recovery was observed for the membrane cholesterol and sphingomyelin, and about 30% recovery was observed for phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine in the DRM were detected using the thin-layer chromatography method. Since the recovery of proteins in DRM was about 10%, the result indicates that there occurs no enrichment of PIP2 in DRM prepared from SPM.  相似文献   
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