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1.
观察17β-雌二醇(17β-estradioI,E2)对去卵巢大鼠下丘脑5-HT1A和5-HT2A受体mRNA表达的影响的时间效应。实验动物分为假去卵巢对照组(OVX+S组)和去卵巢组(OVX)。去卵巢组大鼠又分为雌激素处理组(OVX+E+组)和无雌激素处理组(OVX+E-组),分别在处理后3、6、9和12 d时,采用反转录-聚合酶链式反应(RT-PCR)方法观察5-HT1A和5-HT2A受体mR-NA在大鼠下丘脑的表达。结果显示:5-HT1A和5-HT2A受体mRNA在所有大鼠下丘脑均有表达;5-HT1A受体mRNA在3、6和9 d的OVX+E-组大鼠下丘脑的表达水平明显高于同时间点的OVX-E+组,而5-HT2A受体mRNA在6、9和12 d的OVX+E-组下丘脑的表达量也显著高于同时间点的OVX+E+组。本文结果表明去卵巢后大鼠下丘脑5-HT1A和5-HT2A受体亚型mRNA表达水平升高,17β-雌二醇可下调两种受体的表达。  相似文献   

2.
目的观察大豆异黄酮减轻反式脂肪酸诱导的大鼠动脉粥样硬化的作用。方法将大鼠随机分为普通饲料组、反式脂肪酸组、大豆异黄酮组和反式脂肪酸+大豆异黄酮组,用试剂盒分别测量血中TG、HDL、LDL、IL-6和TNF-α的含量;培养牛主动脉内皮细胞,分为对照组、反式脂肪酸组和反式脂肪酸+大豆异黄酮组,Western blot法检测牛主动脉内皮细胞内NF-κB的磷酸化,同时检测细胞间黏附因子-1(ICAM-1)与血管细胞黏附因子(VCAM-1)蛋白表达。结果与普通饲料组比较,反式脂肪酸组血TG、LDL、IL-6和TNF-α明显升高(P0.05),HDL显著降低(P0.05)。大豆异黄酮干预后,血中TG、LDL、IL-6和TNF-α均降低(P0.01),HDL显著升高(P0.01)。大豆异黄酮能降低反式脂肪酸诱导的NF-κB磷酸化(P0.01);与对照组比较,大豆异黄酮能使反式脂肪酸诱导的ICAM-1和VCAM-1的表达降低(P0.01)。结论大豆异黄酮可减轻反式脂肪酸诱导的大鼠动脉粥样硬化作用。  相似文献   

3.
17βE2对切除卵巢兔动脉粥样硬化与血液流变学的作用   总被引:5,自引:1,他引:5  
目的: 探讨17βE2对卵巢切除(OVX)兔的AS斑块、血脂代谢及血液流变学的影响。方法: 34只成熟未孕雌兔分为4组:A为NC;B为Sham+CHO;C为OVX+CHO;D为OVX+CHO+17βE2。喂养12周,喂养前与12周后测定血脂TC、TG、HDL-C、LDL-C、ApoA1、ApoB;测定全血粘度、血浆粘度、AIRC及纤维蛋白原。喂养12周后处死,测定AS斑块面积与主动脉总面积百分比。结果: ①AS斑块面积与主动脉总面积之比,A、B、C、D组分别为0.02±0.00、0.42±0.15、0.67±0.23、0.12±0.11,B组小于C组(P<0.05)、D组明显小于C组(P<0.01)。②血脂TC、TG、LDL-C、ApoB,B、D组明显小于C组(P<0.01)。③血液流变学:全血粘度、血浆粘度AIRC与纤维蛋白原D组明显低于C组(P<0.01)。结论: 17βE2能抑制脂质斑块沉积,改善血脂代谢,减轻高脂血症,改善血液流变学。这可能是雌激素抑制AS形成的部份机理。  相似文献   

4.
背景:目前对去卵巢大鼠的研究较多,而对不同时间点大鼠骨量、骨转换指标、雌激素水平的变化规律及各因素的相关性研究报道较少。 目的:分析去卵巢大鼠不同时期骨量、骨转换指标、雌激素水平的变化规律并探讨其相关性。 方法:34只3月龄雌性SD大鼠,随机分为基线组、假手术组和去卵巢组。实验开始先将基线组处死,假手术组及去卵巢组于术后第4,8,12周分次处死。双能X射线吸收法(DXA)测定L1-3及股骨不同分区(头颈部R1区、转子部R2区、股骨干R3区、股骨整体R4区)的骨矿含量、骨密度、骨面积;酶联免疫吸附法(ELISA)检测血清Ⅰ型前胶原氨基端原肽、Ⅰ型胶原羧基端肽及雌激素水平。对大鼠体质量、离体骨密度、Ⅰ型前胶原氨基端原肽、Ⅰ型胶原羧基端肽、雌激素水平、月龄间的相关性进行分析。 结果与结论:①去卵巢后4周去卵巢组离体腰椎及股骨骨矿含量、骨密度均较基线组、假手术组明显降低(P < 0.05),第8,12周时均显著改善(P < 0.05),腰椎、股骨各区域骨量丢失幅度最大的为L1及股骨转子区。       ②去卵巢后4周去卵巢组血清Ⅰ型前胶原氨基端原肽、Ⅰ型胶原羧基端肽水平较基线组、假手术组均显著升高(P < 0.05),第8,12周差异无显著性意义。③去卵巢组第8,12周血清雌激素较假手术组及基线组明显降低(P < 0.01,P < 0.05)。④月龄与大鼠体质量、腰椎及股骨骨密度呈正相关,Ⅰ型前胶原氨基端原肽、Ⅰ型胶原羧基端肽与腰椎及股骨骨密度呈负相关(P < 0.01)。提示去卵巢后大鼠腰椎、股骨骨量变化呈先快速降低、再缓慢回升的趋势,其中L1及股骨转子部受影响最大;骨转换指标在去卵巢后显著加快、后期逐渐回归正常;雌激素水平变化规律为第1个月先升高、后期快速降低;体质量、骨转换指标及雌激素水平与骨量密切相关。  中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接:  相似文献   

5.
探讨糖尿病大鼠血管组织糖基化终产物(AGEs)含量与其受体(RAGE)和细胞间粘附因子-1(ICAM-1)表达的关系。复制糖尿病大鼠模型,采用荧光法、RT-PCR及原位杂交方法检测主动脉及心肌组织的AGEs含量以及RAGE和ICAM-1基因的表达。发现糖尿病大鼠主动脉和心肌组织AGEs含量升高(P<0.01);RAGE和ICAM-1基因表达增强(P<0.05-0.05);AGEs含量与RAGE及ICAM-1呈明显正相关(P<0.01);氨基胍治疗可缓解上述指标的变化。提示 AGEs可诱导RAGE和ICAM-1的表达。推测AGEs-RAGE相互作用是引起糖尿病血管内皮细胞功能紊乱和损伤的关键环节。  相似文献   

6.
目的:探讨代谢综合征(MS)患者血糖、血脂对血浆高密度脂蛋白(HDL)亚类组成及含量的影响。方法:收集MS患者组220例和对照组86例的血浆,采用全自动生化分析仪测定血脂及载脂蛋白的浓度,双向电泳-免疫印记检测法测定受试者HDL亚类的相对含量。结果:(1)与对照组相比,MS患者空腹血糖(FPG)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、LDL-C/高密度脂蛋白胆固醇(HDL-C)、载脂蛋白B100(apo B100)、apo B100/载脂蛋白A-I(apo A-I)、收缩压(SBP)、体重指数(BMI)与HDL3b含量均增加(P0.05),而HDLC、apo A-I、preβ2-HDL、HDL2a和HDL2b含量均减少(P0.01)。(2)随着血糖浓度的升高,血浆中HDL2a与HDL2b含量减少(P0.05),preβ1-HDL增加(P0.05)。(3)MS患者随着HDL-C含量的降低,HDL2b含量减少(P0.01),preβ1-HDL增加(P0.01)。(4)MS患者随着TG水平的增加和HDL-C水平的降低,血浆中小颗粒的preβ1-HDL有增加的趋势,而大颗粒的HDL2b有减少趋势,HDL成熟代谢受阻。(5)相关性分析发现FPG与大颗粒的HDL2a和HDL2b呈负相关;HDL-C与HDL2b呈正相关,而与preβ1-HDL呈负相关;TG含量与preβ1-HDL、HDL3b呈正相关。结论:MS患者随着血糖、TG含量的增加及HDL-C含量的减少,大颗粒的HDL2a和HDL2b含量减少,而小颗粒的preβ1-HDL含量增加,HDL颗粒有变小的趋势,HDL颗粒的成熟代谢受阻。  相似文献   

7.
目的建立去卵巢联合糖皮质激素致兔骨质疏松模型,探讨去卵巢联合糖皮质激素对兔骨代谢的影响。方法将18只新西兰雌兔随机分为3组:假手术组(SHAM,生理盐水5 ml·kg-1·d-1);去卵巢组(OVX,生理盐水5 ml/kg/d);去卵巢联合糖皮质激素组(OVX+GC,地塞米松1 mg·kg-1·d-1)。实验第0、3和6周,检测各组大白兔腰椎(3~6)和右侧股骨的骨密度。实验结束时,取右侧股骨进行生物力学检测;取第3腰椎进行骨组织形态计量学检测。结果与SHAM组相比,OVX+GC组大白兔骨密度、骨生物力学性能(最大载荷、断裂载荷等)、骨小梁面积百分数、骨小梁厚度和骨小梁数量均显著降低(P<0.05),骨小梁分离度显著升高(P<0.05),而OVX组大白兔的均无显著差异。结论去卵巢联合糖皮质激素法建立兔骨质疏松模型切实可行,而且效果优于单纯去卵巢兔骨质疏松模型。  相似文献   

8.
目的 观察大鼠母体孕期高脂高糖饮食对子代成年期动脉粥样硬化的影响。方法 20只雌性大鼠分成普食组(P组)和高脂高糖组(G组),孕期分别喂养两种饲料,G组子代雄性鼠分为高脂高糖组(G—G组)和普通饲料组(G—P组),P组子代雄性鼠仍普通饲料喂养(P—P组),子代大鼠12周末检测其血清氧化型低密度脂蛋白(OX—LDL),总甘油三脂(TG),总胆固醇(TC),高密度脂蛋白-C(HDL—C)及低密度脂蛋白-C(LDL—C)的浓度,同时利用HE染色切片观察子代成年大鼠主动脉的脂质沉积情况。结果 ①成年子代血清OX—LDL,TC和LDL—C浓度:在子代高营养组(P—G,G—G组)较子代普食组(P—P组)明显增高(P〈0.01);在母亲高营养子代高营养组(G—G)较母亲高营养子代普食组(G—P)明显增高(P〈0.05)。②血清TG和HDL—C浓度在各组无显著差异性(P〈0.05。③母体孕期高营养的子代主动脉脂纹发生率在G—G组最高,G—P组次之,P—P组最低。结论 母体孕期高营养饮食对子代成年期动脉粥样硬化有着重要的影响,子代在生长过程中普通饮食有利于延缓或防止动脉粥样硬化的发生。  相似文献   

9.
以假手术大鼠(Sham)作为对照组,切除大鼠双侧卵巢(OVX)后,血浆17β-雌二醇(17β-E2)水平下降48%。体重增加17%(P<0.001),血清总胆固醇(TC)含量升高约50%(P<0.001),甘油三酯(TG)含量降低30%(P<0.01)。OVX后进行雌激素替代疗法(ERT)各组(ERT1-3)的TC和TG的含量分别下降(P>0.05)到和升高(P<0.01)至高于对照组的水平。给于雌激素受体拮抗剂──它莫西芬(TAM)的各组(TAM,OVX+TAM,ERT3+TAM)中,血清TC和TG含量均低于对照组(P<0.01~P<0.001)。此外,OVX组血浆降钙素基因相关肽(CGRP)和内皮素水平也分别降低为对照组的69%和89%(P<0.05)。提示卵巢激素主要是雌激素通过其受体介导参与大鼠脂代谢和体重的调节,ERT和TAM对OVX大鼠血清TC浓度及体重的调节产生有利影响。OVX大鼠血浆CGRP和内皮素水平的调节可能与雌激素水平变化有关。  相似文献   

10.
目的:研究内源性高甘油三酯血症(HTG)患血浆极低密度脂蛋白(VLDL)、低密度脂蛋白(LDL)及高密度脂蛋白(HDL)是否发生了氧化修饰及其对血凝的影响。方法:对2l例内源性高甘油三酯血症患与2l例年龄性别相近的正常人的血脂、脂质过氧化物进行了分析。用一次性密度梯度超速离心法分离血浆VLDL、LDL及HDL,测定这三种脂蛋白的234nm光吸收、相对电泳迁移率(REM)和硫代巴比妥酸反应物质(TBARS),分别将这三种脂蛋白加入由正常人新鲜混合血浆构成的反应系统中,按试剂盒分别测定凝血酶原时间(PT)及活化部分凝血酶原时间(APIT)。结果:内源性HTG患血浆TG含量平均升高2.73倍,HDLC下降l.7l倍,同时LPO升高1.22倍;HTG组VLDL、LDL及HDL的REM、234nm光吸收值、TBARS含量均较对照组显增加(P<0.01),表明内源性HTG患血浆VLDL、LDL及LDL均发生了氧化修饰生成Ox—VLDL、Ox-LDL.PT及APTT在分别加入HTG组的VLDL、LDL及HDL后均比加入相应正常组脂蛋白明显缩短(P均<0.05)。相关分析表明,HTG组血浆VLDL及HDL相对电泳迁移率(REM)与PT呈负相关(P<0.01)。结论:HTG患血浆VLDL、LDL及HDL发生了氧化修饰,并使PT及APTT明显缩短。  相似文献   

11.
The theta-behaviour of poly(p-tert-butylstyrene)-block-poly(dimethylsiloxane)-block-poly(p-tert-butylstyrene) ABA type triblock copolymers containing ca. 28% by weight tert-butylstyrene was studied in the selective solvents 1-nitropropane and 2-butanone using the phase separation method. The theta-temperatures in these solvents were found to be 157°C and 31°C, respectively. The intrinsic viscosities of the copolymers in 2-butanone (MEK) were obtained at different temperatures. The Mark-Houwink-Sakurada exponent α in MEK at 31°C is greater than 0,5, suggesting that the theta-behaviour of block copolymers is different from that of the homopolymers due to the presence of repulsive interactions between incompatible blocks.  相似文献   

12.
窄手蚋 (Simulium (Simulium) omorii)是Takahasi(1942)发表的新种,当时放在短蚋属(Omiadag),该蚋标本是采自我国黑龙江省.Takahasi 仅描述了两性成虫和蛹,缺幼虫,况前者也不甚详细 1983年,虞以新和安继尧在我国黑龙江省饶河县珍宝岛地区,采到窄手蚋的两性成虫、幼虫和蛹,描述于后供同道者参考.窄手蚋与Rubzov(1956)描述的S. (S.) tenuimanus Enderlein, 1920很近似,不同的是:1. 足色:雌虫,窄手蚋前、中足股节黑色,后足股节基段1/5棕黄色.tenuimanus蚋,前、中、后足股节巧克力棕黑色,仅基部有点黄色.雄虫,窄手蚋后足转节、股节基端部、胫节基端部和中足基节1/2棕黄色,而tenuimanus 除前足基节和后足胫节基部褐色外,余部黑色.2. 窄手蚋中骨圆形或弹头形,前端圆形,后端凹入呈八字形 tenuimanu 中骨箭形,末端尖.标本保存于军事医学科学院医学昆虫标本馆.  相似文献   

13.
Loo JS  Ooi CP  Boey FY 《Biomaterials》2005,26(12):1359-1367
This paper seeks to examine the effects of electron beam (e-beam) radiation on biodegradable polymers (PLGA and PLLA), and to understand their radiation-induced degradation mechanisms. PLGA (80:20) and PLLA polymer films were e-beam irradiated at doses from 2.5 to 50 Mrad and the degradation of these films were studied by measuring the changes in their molecular weights, FTIR spectra, thermal and morphological properties. The dominant effect of e-beam irradiation on both PLGA and PLLA is chain scission. Chain scission occurs first through scission of the polymer main chain, followed by hydrogen abstraction. Chain scission, though responsible for the reduction in the average molecular weight, Tc, Tg and Tm of both polymers, encourages crystallization in PLGA. PLLA also undergoes chain scission upon irradiation but to a lesser degree compared to PLGA. The higher crystallinity of PLLA is the key factor in its greater stability to e-beam radiation compared to PLGA. A linear relationship is also established between the decrease in molecular weight with respect to radiation dose.  相似文献   

14.
We report on a 5-month-old girl with widely spaced nipples, redundant nuchal skin, coarctation of the aorta, anal atresia with distal fistula, postnatal growth retardation, hypotonia, and sparse scalp hair. Initial clinical assessment suggested the diagnosis of Ullrich-Turner syndrome. Chromosome analysis showed a 46,XX,del(2)(q37) karyotype in peripheral lymphocytes. We compare her findings to those of other reported patients with terminal deletions of 2q. © 1994 Wiley-Liss, Inc.  相似文献   

15.
在研究可溶性gp130(sgp130)分子对IL 6/IL 6R作用的基础上,继续研究了sgp130对IL 6家族细胞因子白血病抑制因子(LIF)和制瘤素(OM)的生物学作用。结果显示,sgp130对LIF和OM刺激的人多发性骨髓瘤(MM)细胞株XG4 CNTF的增殖有抑制作用。此外,sgp130对LIF和OM刺激表达LIF受体的新鲜MM细胞的增殖也有抑制作用,提示sgp130也可为LIF和OM的拮抗剂。  相似文献   

16.
17.
Two series of triblock copolymers of poly(ethylene glycol) (PEG, number-average molecular weight M n = 6000) and poly(L -lactide) (PLLA) or poly(D -lactide) (PDLA) were prepared by ring-opening polymerization of lactide initiated by PEG end groups using stannous octoate as a catalyst, either in refluxing toluene or in the melt at 175°C. The weight percentage of PLA in the polymers varied between 15 and 75 wt.-%. Blends of polymers containing blocks of opposite chirality were prepared by co-precipitation from homogeneous solutions. The melting temperatures of the crystalline PEG and PLA phases strongly depended on the composition of the polymers. The melting temperature of the PLA phase in the blends was approximately 40°C higher than that of the single block copolymers. Stereocomplex formation between blocks of enantiomeric poly(lactides) in PEG/PLA block copolymers was established for the first time. Water uptake of polymeric films prepared by solution casting was solely determined by the PEG content of the film.  相似文献   

18.
Four novel analogues of (E)-5-(2-bromovinyl)-2'-deoxyuridine [(E)-BrVUdR]--the (E)- and (Z)-isomer of 5-(2-fluorovinyl)-UdR (FVUdR), (Z)-5-(2-carboxy-2-fluorovinyl)-UdR [(Z)-COOH-FVUdR], and (E)-5-(2-ethoxyvinyl)-UdR [(E)-EOVUdR] were compared with the reference compounds (E)-BrVUdR and 5-vinyl-UdR (VUdR) for their inhibitory effects on plaque formation of herpes simplex virus type 1 (HSV-1 strain 77) and type 2 (HSV-2 strain 82) in human embryonic lung fibroblast (HELF) cell cultures. (Z)-FVUdR and (Z)-COOH-FVUdR were completely inactive against HSV-1 and HSV-2 (ID50 greater than 500 microM). For the other analogues the following order of decreasing potency was found: (E)-BrVUdR greater than VUdR greater than (E)-FVUdR much greater than (E)-EOVUdR (against HSV-1) and VUdR much greater than (E)-BrVUdR greater than (E)-FVUdR much greater than (E)-EOVUdR (against HSV-2).  相似文献   

19.
20.
The reaction of a living poly(tetrahydrofuran) (poly(THF)), prepared with methyl trifluoromethanesulfonate as an initiator, with 3-sodiopropoxydimethylvinylsilane was carried out to produce a uniform poly(THF) macromonomer with a vinylsilane end-group. Poly(vinyl acetate)-graft-poly(THF) of controlled graft segment length was then synthesized through radical copolymerization of this poly(THF) macromonomer with vinyl acetate. The subsequent saponification with NaOH in methanol provided poly(vinyl alcohol)-graft-poly(THF).  相似文献   

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