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71.
Summary The fine structure of intracellular and extracellular lipids in the atherosclerotic aorta of Watanabe-heritable hyperlipidemic (WHHL) rabbits was demonstrated by a quick-freeze etching technique. Many lipid droplets, with and without a membrane, were observed in the foam cells. Membrane-free droplets were observed as onionlike structure with a concentric lamellar structure surrounded by 10 nm filaments. Droplets surrounded by a limited membrane probably correspond to lipid-laden lysosomes.In the extracellular connective tissue space, marked accumulation of lipids with a vesicular structure was seen among collagen fibers. The appearance of these lipids was similar to that of lipids in lysosomes of foam cells.  相似文献   
72.
检测体外培养和体内发育过程中,胎鼠胸腺处于不同发育阶段时Toll样受体(TLR)的表达,阐明TLR表达量与胸腺细胞发育相关性,为TLR和胸腺细胞发育分化相关研究提供基础数据。无菌取15d胎龄胎鼠胸腺进行体外培养(FTOC),在培养不同时间点(2d,4d,6d),检测处于不同发育期胸腺TLR的表达;同时在孕期不同天数(15~19d),分别取胎鼠胸腺,检测在体内发育过程中胸腺TLR的表达;在FTOC中加入二脱氧鸟苷培养6d以制备胸腺基质细胞,检测基质细胞与胸腺细胞TLR表达情况。结果:小鼠胸腺中检测到多种TLR。FTOC培养中:培养第2天(F2)开始检测到各种TLR,到培养第6天(F6),TLR1,TLR3,TLR6,TLR7,TLR8明显上调,而TLR4,TLR5保持低水平,TLR4在培养第6天又下降;体内发育过程中:TLR6表达量随胎龄增加有较明显上调,TLR1,TLR3-8保持低水平表达;TLR2,TLR9体内体外都未检测到明显表达。在对胸腺细胞与基质细胞TLR表达比较中发现TLR1,TLR5,TLR6,TLR7高表达于胸腺细胞。胎鼠胸腺表达某些TLR,并且在发育不同阶段表达量有所改变,提示TLR可能参与胸腺细胞的发育过程。  相似文献   
73.
徐存拴  蔺芳  秦少伟 《解剖学报》2008,39(3):302-309
目的在基因转录水平了解脂类代谢和运输相关基因在大鼠肝再生(LR)中的表达变化和模式。方法用搜集网站资料和查阅相关论文等方法获得参与脂类代谢和运输基因,用大鼠基因组230 2.0芯片检测它们在大鼠再生肝中的表达情况,用比较手术和假手术中基因表达的差异性确定肝再生相关基因。结果初步证实上述基因中193个基因与肝再生相关。肝再生早期[部分肝切除(PH)后0.5~4h]、前期(PH后6~12h)、中期(PH后12~66h)、后期(PH后72~168h)等4个阶段起始表达的基因数为113、20、66和1;基因的总表达次数为250、205、796和293。共上调852次,下调630次,分为27种表达方式。肝再生早期和前期胆汁酸代谢相关基因转录减弱;早期和后期糖皮质激素分解相关基因转录增强;前期和中期磷脂合成相关基因转录增强,磷脂分解相关基因转录减弱;中期脂肪酸、白三烯和鞘糖脂合成相关基因转录增强,甘油三酯和磷脂酰肌醇代谢相关基因转录增强,鞘糖脂分解相关基因转录减弱;中期和后期前列腺素合成和脂肪酸分解相关基因转录增强;几乎在整个肝再生中性激素、糖皮质激素和孕酮合成相关基因转录增强,鞘磷脂代谢相关基因转录增强,脂类运输相关基因转录增强,胆固醇代谢相关基因转录减弱。结论肝再生中脂类代谢和运输变化较大,与肝再生密切相关。  相似文献   
74.
肾阳虚证患者红细胞LPO、SOD和ATP酶活性的变化   总被引:6,自引:0,他引:6  
目的 :探讨肾阳虚证患者红细胞LPO、SOD和ATP酶活性的特点及其意义。方法 :观察 19例肾阳虚证患者和 2 1例正常人红细胞LPO、SOD和红细胞膜Na+ K+ ATP酶、Mg2 + ATP酶、Ca2 + ATP酶、Ca2 + Mg2 + ATP酶活性的变化。结果 :与对照组比较 ,肾阳虚证患者红细胞LPO含量升高 (P <0 .0 1) ,红细胞SOD活性降低 (P <0 .0 1) ;红细胞膜Na+ K+ ATP酶活性显著升高 (P <0 .0 1) ,而Mg2 + ATP酶活性变化无显著性差异 ,Ca2 + ATP酶活性升高 (P <0 .0 1) ,Ca2 + Mg2 + ATP酶活性也显著升高 (P <0 .0 1)。结论 :肾阳虚证患者红细胞内脂质过氧化反应增强 ,而抗氧化能力降低 ,红细胞膜Na+ K+ ATP酶、Ca2 + ATP酶和Ca2 + Mg2 + ATP酶活性升高 ;本研究为理解肾阳虚证的病理生理基础提供了初步实验依据  相似文献   
75.
Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals.  相似文献   
76.
Metabolic pathways leading to lipid biosynthesis in four different developmental stages of Schistosoma mansoni were explored and quantified by incubation in the presence of labeled precursors in a chemically defined medium. At the schistosomulum stage and in male, female, or paired worms, glycerol and oleate incorporation into neutral lipids, mainly in the form of triacylglycerols, was greater than into phospholipids, whereas in 11-and 15-day-old worms, synthesis mainly led to phospholipids. Incorporation into phospholipids was recovered largely in phosphatidylcholine, and distribution into other phospholipids depended on the developmental stage. Incorporation of choline and ethanolamine into their respective phospholipids represented up to 15% of the parasitic phospholipid content. The formation of phosphatidylcholine by phosphatidylethanolamine methylation occurred mainly in the immature parasitic stages. Inositol incorporation was also measurable, whereas [14C]serine incorporation was low or undetectable. Addition of 1-palmitoyl-2-[14C]oleyl phosphatidylcholine revealed a very high uptake of this phospholipid by the immature stages but further metabolism was not detectable. In contrast, adult S. mansoni were completely unable to take up or absorb this exogenous phospholipid. The most striking aspect of this study was the relatively high metabolic activity in 11-day-old worms and the lower but sustained activity on day 15 and at the schistosomulum stage. By comparison, biosynthetic activity in adult S. mansoni, on which research studies have been focused until now, was very low. We also discuss the participation of lipid metabolism in the constant renewal of the membrane complex which is essential to parasitism by S. mansoni.  相似文献   
77.
山莨菪碱对家兔动脉粥样硬化的抑制作用   总被引:1,自引:0,他引:1  
用65只日本兔喂高脂饲料,观察山莨菪碱对动脉粥样硬化形成的作用及其有关检测指标的影响。结果表明,山莨菪碱组主动脉内膜粥样硬化斑块面积、胆固醇含量、内膜通透性及血液TC、LDL-C、TG、LPO、TXA_2、5-HT、Pt聚集力,血液流变学等,均显著降低;PGI_2及SOD增高;组织光镜及电镜改变减轻。说明山茛菪碱对动脉粥样硬化的形成有显著抑制作用。  相似文献   
78.
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   
79.
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   
80.
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   
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