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1.
利用酶联亲和组织化学法和ABC免疫组织化学法进行88例胃肠肿瘤的雌激素受体(ER)、孕激素受体(PR)和癌胚抗原(CEA)的检测.结果表明:ER、PR、CEA的阳性率分别为37.5%(33/88)、27.3(24/88)、88.64(78/88)。ER、PR的阳性率与肿瘤的组织学分类及病理分级有关。CEA仅与病理分级有关。且与性激素受体水平呈负相关。因此,性激素受体与CEA的表达提供了肿瘤组织不同的生物学特征,同时检则ER、PR及CEA水平对内分泌治疗及判断预后更有价值。  相似文献   

2.
ERβ--一种新型的雌激素受体   总被引:3,自引:0,他引:3  
黄朝晖  王金福 《生命科学》2000,12(3):126-129
介绍了一种新型的雌激素受体ERβ,对其基因及蛋白结构、分布、作用机制方面的研究进展作了综述,并将其与的雌激素受体ERα作了比较。  相似文献   

3.
利用体外翻译系统,翻译了能与雌激素效应元件(ERE)结合的全长的人雌激素受体(hER)。制备了切除卵巢的雌性大鼠子宫核抽提物,在雌激素存在下,此核抽提物能增强hER与ERE的结合。此核抽提物在50℃保温15min后,明显减弱了增强hER-ERE结合的作用。提示了核抽提物中存在着能增强hER-ERE结合的雌激素依赖的热敏感性的辅助因子。在大肠杆菌中表达了谷胱甘肽转硫酶(GST)融合的雌激素受体的DN  相似文献   

4.
电针对大鼠脑内雌激素受体蛋白及其mRNA表达的影响   总被引:24,自引:1,他引:23  
Chen BY  Cheng LH  Gao H  Ji SZ 《生理学报》1998,50(5):495-500
本文应用放射免疫分析(RIA)、RNA点杂交和Northern blot、单克隆抗体免疫组织化学和计算机图像处理技术研究电针对切除卵巢大鼠脑内雌激素受体(ER)蛋白和mRNA表达的影响。以探讨针刺作用的分子生物学机理。结果表明,切除卵巢可导致血雌二醇(E2)水平降低,动物脑内ER蛋白和mRNA的表达增强;电针实验穴位后,去卵巢大鼠血的E2含量明显增加,脑内ER蛋白和mRNA表达受到明显抑制。正常大  相似文献   

5.
中期孕鼠在他莫昔芬作用下,其颌下腺,血清中EGF含量下降,胎盘中EGF受体结合位点数下降以及它的mRNA表达受到抑制,再次证实了他莫昔芬抑制雌激素诱导EGF受体mRNA的表达。从而使EGF受体结合位点数减少,因此,他莫昔芬对孕鼠胚胎生长发育有不可忽视的影响。  相似文献   

6.
本文应用凝集素亲和细胞化学的方法,通过荧光标记的麦胚凝集素(FITC-WGA)对培养的大鼠脑微血管内皮细胞进行染色,观察了WGA凝集素受体在缺氧-再给氧后脑微血管内皮细胞上的表达。通过图像分析定量细胞表面的荧光强度,发现脑微血管内皮细胞单纯缺氧6小时后凝集素受体表达与正常对照组相比无明显变化;其显著改变发生于再给氧1小时后,WGA的结合位点明显增加,荧光强度达峰值;再给氧3小时及6小时后有所下降,但与正常对照组相比仍具有显著性差异。上述结果与我们以往的动物在体实验,即大鼠脑缺血-再灌注后内皮细胞WGA受体的表达趋势相吻合。说明脑微血管内皮细胞凝集素受体在细胞损伤后发生改变,并显示了在单纯缺血损伤和再灌注损伤的表达有所不同,它与其它内皮损伤后的变化,如细胞因子及其受体、粘附分子等的关系有待于深入研究  相似文献   

7.
中期孕鼠在他莫昔芬作用下,其颌下腺,血清中EGF含量下降,胎盘中EGF受体结合位点数下降以及它的mRNA表达受到抑制,再次证实了他莫昔芬抑制雌激素诱导EGF受体mRNA的表达,从而使EGF受体结合位点数减少,因素,他莫昔芬对孕鼠胚胎生长发育有不可忽视的影响。  相似文献   

8.
建立了测定人乳腺癌胞浆cAMP结合蛋白(cAMPb.p.)方法。综合研究了其温度、保温时间、配体浓度、稳定性等条件。cAMPb.p.的K_D值为2.90×10~(-8)mol/L.并测定了60例雌激素受体(ER)Fu性乳腺癌标本的cAMPb.p.含量。此组病人术后均接受系统的内分泌治疗,ER/cAMPbp,比值范围为7.7~362×10~(-3),ER/cAMPb.p.比值≥40×10~(-3)的五年生存率明显高于比值<40×10~(-3)组,(p<0.005).表明测定ER/cAMPb.p.比值对预测患者内分泌治疗疗效,优于单独测定ER.  相似文献   

9.
在大鼠动情前期促黄体生成激素峰形成前后测定了血清雌、孕激素水平变化、下丘脑正中隆起促黄体生成激素释放激素含量及弓状核区雌、孕激素受体密度改变和弓状核前阿黑皮素mRNA水平变化。结果表明:动情前期14小时时血清雌激素水平开始升高(P<005),于16小时时达高峰。此时弓状核雌激素受体密度降低(P<005),孕激素受体密度增加(P<005),前阿黑皮素mRNA水平减少(P<005)。前阿黑皮素mRNA水平与血清雌激素及正中隆起的促性腺激素释放激素水平呈负相关(P值分别小于001及005),与弓状核雌激素受体密度变化呈正相关(P<001)。提示弓状核的前阿黑皮素mRNA水平在此过程中可能受雌激素及其受体调控,下丘脑β内啡肽合成减少可能参与了排卵前促性腺激素释放激素/促黄体生成激素峰的形成。  相似文献   

10.
为了鉴定人血管紧张肽原(AGT)基因的雌激素调控元件,在AGT基因转录起始点和TATA框之间的一段核苷酸序列与雌激素应答元件共有寡核苷酸序列高度同源,通过电泳迁移率变动分析,证明该DNA序列为雌激素应答元件(HAG ERE)。将带有HAGERE的AGT基因核心启动子同氯霉素乙酰转移酶(CAT)报道基因融合,或将多拷贝HAG ERE同TK核心启动子连接,再与CAT基因融合,构成表达载体,与人雌激素  相似文献   

11.
Preparations, XPS and electronic spectroscopy, and magnetism of seven new one-dimensional cyano-bridged coordination polymers, chiral [Cu(RR-chxn)2][Pd(CN)4] · 2H2O (1), [Cu(trans-chxn)2][M(CN)4] · 2H2O (2, 4, and 6 for M = Pd, Ni, and Pt), and [Cu(cis-chxn)2][M(CN)4] · 2H2O (3, 5, and 7 for M = Pd, Ni, and Pt) (RR-chxn = cyclohexane-(1R,2R)-diamine, trans-chxn = racemic trans-cyclohexane-(1,2)-diamine, and cis-chxn = racemic cis-cyclohexane-(1,2)-diamine) have been reported in view of tuning of their electronic properties by stereochemistry of chxn ligands and metal-substitution. Comparison of Cu 2p1/2 and 2p3/2 peaks of XPS and broad d-d bands around 18 000 cm−1 of electronic spectra are described systematically for 1-7. Variable-temperature magnetic measurement shows that complexes 1-7 indicate weak antiferromagnetic interactions via cyano-bridges. Because of semi-coordination coupled with pseudo Jahn-Teller elongation and electrostatic interaction for 1, the axial Cu-N coordination bond distances of 2.330(7) and 3.092(8) Å are considerably longer than those of equatorial ones in the range from 2.016(6) to 2.030(6) Å. The former bond distances of 1 are intermediate values among the related Ni (2.324(6) and 3.120(8) Å) and Pt (2.34(1) and 3.09(1) Å) complexes.  相似文献   

12.
Over the past 10 years, Ghusel VDC, Lalitpur District has moved from primarily subsistence agriculture into the wider cash economy aided by the Small Farmers' Development Program (SFDP), which provides credit to farmers mainly for the purchase of buffalo for milk production, and by the National Dairy Corporation, which supports local dairy cooperatives. Analysis reveals that buffalo-keeping and milk sales are increasing the well-being of many households, while at the same time creating new inequalities in gender roles and responsibilities, greater inequities between Brahmin and Tamang residents in Ghusel, and placing pressures on the ecosystem for increased supplies of fodder and fuelwood. Evidence suggests that there is critical, need for attention to the social, and particularly gender-based, implications of maintaining livestock for milk sales and to the ecological underpinnings of this livelihood system.  相似文献   

13.
Structure and function of S-adenosylhomocysteine hydrolase   总被引:6,自引:0,他引:6  
In mammals, S-adenosylhomocysteine hydrolase (AdoHcyase) is the only known enzyme to catalyze the breakdown of S-adenosylhomocysteine (AdoHcy) to homocysteine and adenosine. AdoHcy is the product of all adenosylmethionine (AdoMet)-dependent biological transmethylations. These reactions have a wide range of products, and are common in all facets of biometabolism. As a product inhibitor, elevated levels of AdoHcy suppress AdoMet-dependent transmethylations. Thus, AdoHcyase is a regulator of biological transmethylation in general. The three-dimensional structure of AdoHcyase complexed with reduced nicotinamide adenine dinucleotide phosphate (NADH) and the inhibitor (1′R, 2′S, 3′R)-9-(2′,3′-dihyroxycyclopenten-1-yl)adenine (DHCeA) was solved by a combination of the crystallographic direct methods program, SnB, to determine the selenium atom substructure and by treating the multiwavelength anomalous diffraction data as a special case of multiple isomorphous replacement. The enzyme architecture resembles that observed for NAD-dependent dehydrogenases, with the catalytic domain and the cofactor binding domain each containing a modified Rossmann fold. The two domains form a deep active site cleft containing the cofactor and bound inhibitor molecule. A comparison of the inhibitor complex of the human enzyme and the structure of the rat enzyme, solved without inhibitor, suggests that a 17° rigid body movement of the catalytic domain occurs upon inhibitor/substrate binding.  相似文献   

14.
Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G‐type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical‐scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(–) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(–) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. Chirality 26:817–824, 2014. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc.  相似文献   

15.
The aim of the study has been to determine and compare the influence upon the kidney antioxidative system, exercised by administration of vitamin E, and vitamin E in combination with methionine, under conditions of oxidative stress induced by sodium fluoride. The experiment was carried out on Wistar FL rats (adult males) that, for 35 days, were administered water, NaF, NaF with vitamin E, or vitamin E with methionine (doses: 10 mg NaF/kg of body mass/24 h, 3 mg vitamin E per 10 μl per rat for 24 h, 2 mg methionine per rat for 24 h). The influence of administered sodium fluoride and antioxidants upon the antioxidative system in kidney was examined by analyzing the concentration of malondialdehyde (MDA) and the activity of the most important antioxidative enzymes (SOD, total and both its isoenzymes, GPX, GST, GR, and CAT). The studies carried out confirmed the disadvantageous effect of the administered dose of NaF upon the antixodiative system in rats (increase in the concentration MDA, decrease activity of all antioxidative enzymes). The administration of vitamin E increased the activity of studied enzymes with the exception of glutathione reductase GR; it also reduced the procesess of lipid peroxidation. It has been found that combined doses of vitamin E and methionine were most effective in inhibiting lipid peroxidation processes. The results confirmed the antioxidative properties of methionine.  相似文献   

16.
Auxin-mediated elongation growth of isolated subapical coleoptile segments of maize (Zea mays L.) is controlled by the extensibility of the outer cell wall of the outer epidermis (Kutschera et al., 1987). Here we investigate the hypothesis that auxin controls the extensibility of this wall by changing the orientation of newly deposited microfibrils through a corresponding change in the orientation of cortical microtubules. On the basis of electron micrographs it is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface. Conversely, reinduction of growth by exogenous auxin is correlated with a relative increase of transversely orientated microfibrils and microtubules at the inner wall surface. These changes can be detected 30–60 min after the removal and addition of auxin, respectively. The functional significance of directional changes of newly desposited wall microfibrils for the control of elongation growth is discussed.  相似文献   

17.
Mycobacterium tuberculosis (M.tb.), the causative agent of tuberculosis (TB), cannot synthesize GSH, but synthesizes two major low molecular weight thiols namely mycothiol (MSH) and ergothioneine (ERG). Gamma-glutamylcysteine (GGC), an intermediate in GSH synthesis, has been implicated in the protection of lactic acid bacteria from oxidative stress in the absence of GSH. In mycobacteria, GGC is an intermediate in ERG biosynthesis, and its formation is catalysed by EgtA (GshA). GGC is subsequently used by EgtB in the formation of hercynine-sulphoxide-GGC. In this study, M.tb. mutants harbouring unmarked, in-frame deletions in each of the fives genes involved in ERG biosynthesis (egtA, egtB, egtC, egtD and egtE) or a marked deletion of the mshA gene (required for MSH biosynthesis) were generated. Liquid chromatography tandem mass spectrometry analyses (LC-MS) revealed that the production of GGC was elevated in the MSH-deficient and the ERG-deficient mutants. The ERG-deficient ΔegtB mutant which accumulated GGC was more resistant to oxidative and nitrosative stress than the ERG-deficient, GGC-deficient ΔegtA mutant. This implicates GGC in the detoxification of reactive oxygen and nitrogen species in M.tb.  相似文献   

18.
The mitogenic responses of separated rabbit lymphocyte populations functionally analogous to mouse T and B cells have been tested in vitro. Purified T cells were prepared by passage over nylon wool (NW) and purified B cells prepared by treatment with antithymocyte serum and complement (ATS + C). ATS + C kills 70% of peripheral blood lymphocytes (PBL's) and 50% of the spleen cells while passage over NW yields 40% of the applied PBL's and 5–23% of the applied spleen cells. NW-purified T cells from the spleen or PBL's respond fully to concanavalin A (Con A) but have a reduced response to phytohemaglutinin (PHA) and little or no response to goat anti-rabbit immunoglobulin (anti-Ig). PBL's that survive ATS + C (B cells) are stimulated by anti-Ig but not by Con A or PHA. B cells purified from spleen do not respond to Con A or PHA but will respond to anti-Ig under appropriate conditions. A full spleen B-cell response to anti-Ig required removal of Ig produced by the cultures that blocked anti-Ig stimulation. It is concluded that, for rabbit lymphocytes, Con A and PHA are primarily T-cell mitogens and that anti-Ig is primarily a B-cell mitogen. However, the mitogen response of unfractionated PBL or spleen cell populations indicates an overlap in reactivity. This could be due to cells sharing T and B properties, alteration of cell populations by the fractionation procedures used, or recruitment of one population in the presence of a mitogenic response of the other population.  相似文献   

19.
八种脑-肠肽侧脑室内注射对大鼠基础胃酸分泌的影响   总被引:1,自引:0,他引:1  
用乌拉坦麻醉大鼠作急性实验,采用连续灌流胃并收集流出液的方法,观察向侧脑室内注射微量脑-肠肽对大鼠基础胃酸分泌的影响。实验结果如下:(1)雨蛙肽、八肽胆囊收缩素、促甲状腺素释放激素及四肽胃泌素均使总酸排出量增加;(2)生长抑素、胰多肽、P 物质、胰高血糖素则使总酸排出量减少;(3)上述肽类用侧脑室注射的剂量作肌肉注射,除四肽胃泌素也产生明显的刺激胃酸分泌作用外,对胃酸分泌均无明显影响。以上结果提示,脑内的一些肽类可能以神经递质或调制物的方式,参与中枢对胃酸分泌的调节。  相似文献   

20.
In this paper, a kind of Typhaceae plant species, Typha angustifolia L, with a high tolerance to Cr is described. Experiments were carried out to examine its ability to tolerant Cr and its physiological response. The results showed that there was no difference in growth, plant height, and biomass response to external Cr (VI) between the plants exposed to 100 microM Cr (VI) and control (0 microM), while increasing Cr levels to 200-800 microM induced a significant decrease in plant height and biomass, but no significant injury was detected, even for the plants exposed to 800 microM Cr. Chromium induced significant increases in superoxide dismutase (SOD) and peroxidase (POD) activities. Meanwhile, a significantly positive correlation was found between Cr and Mn or Cu in leaves and roots, respectively. The Cr tolerance of the plant appeared to be associated with the enhancement of SOD and POD activities and the improvement in uptake and translocation of the essential microelements.  相似文献   

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