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111.
The brain and the thoracic ganglion of a crustacean can synthesize and secrete gonad-stimulating hormone (GSH) which stimulates the maturation of gonad. In the previous experiments, sex steroid hormones (estradiol, testosterone, progesterone, etc.) have been detected from the crustacean. However, the feedback regulation of sex steroid hormones on the brain and the thoracic ganglion of the crustacean has not been reported so far. In the present experiment, monoclonal antibodies were applied to investigate the immunorecognition of estrogen receptor (ER) and androgen receptor (AR) in the brain and the thoracic ganglion mass of Scylla paramamosain. The results showed that the distribution of the immunopositive substances of ER and AR was extremely similar. They distributed in the protocerebrum, deutocerebrum and tritocerebrum of the brain, and mainly in protocerebrum. In the thoracic ganglion mass, immunopositive substances distributed in the subesophageal ganglion, thoracic ganglion and abdominal ganglion, and mostly in subesophageal ganglion. Immunopositive substances of ER and AR mostly existed in the cytoplasm of neurons. The present study will provide morphological evidence for the origin and the evolution of ER and AR. In addition, the immunoreactivities of ER and AR suggested that the estrogen and androgen may be involved in the feedback regulation of crustacean neuroendocrine.  相似文献   
112.
A 1063 bp cDNA clone encoding a putative 37 kDa laminin receptor precursor (37 kDa LRP) is isolated from the mantle tissue of pearl oyster, Pinctadafucata. The amino acid sequence predicted from the cDNA sequence is 301 residues long, with a calculated molecular mass of 33.5 kDa. RT-PCR analysis shows that 37 kDa LRP mRNA is especially highly expressed in the mantle while widely expressed in several tissues. In situ hybridization analysis reveals that 37 kDa LRP is expressed in the outer epithelial ceils of the mantle edge, suggesting its involvement in cell proliferation and secretion in P. fucata. The identification and characterization of 37 kDa LRP in the pearl oyster will help us to further understand the signal transduction in the processes of mantle epithelial cell proliferation and tissue formation.  相似文献   
113.
目的:研究人类β2肾上腺素能受体(ADRβ2)基因C659G变异与新疆哈萨克族甘油三酯水平间的关系.方法:采用多聚酶链式反应法及限制性内切酶片段长度多态性技术(PCR—RFLP),对435例新疆哈萨克族人进行ADR&基因C659G多态性检测,观察基因型和等位基因的分布频率及其与血清甘油三酯水平的关系.结果:435例哈萨克族人ADRβ2基因C659G基因型频率分别为CC85.747%、CG13.793%、GG0.64%,等位基因频率分别为C7.356%、G92.644%,分布符合Hardy—Weinberg定律.按照年龄分组后通过协方差分析扣除体重指数、平均动脉压对血清TG的影响后,可以看到各年龄分组中CG+GG组与CC组血清TG水平均无统计学意义.结论:新疆哈萨克族人β2AR基因C659G多态性与血清甘油三酯水平无关.  相似文献   
114.
在一种仿G蛋白耦合型信号转导的人工超分子系统中引入一类偶氮苯结构的化合物,用来模拟跨膜受体。以苯胺为原料,合成几种人工受体中间体-偶氮苯化合物,选取其中4,4’-二羧基偶氮苯与谷氨酸甲酯(GluOMe)进行连接,得到一种氨基酸甲酯偶氮苯衍生物(Azo-AAOMe),并对其1H NMR谱进行了研究。核磁谱图显示,所合成的化合物正是预期产物。  相似文献   
115.
Liu  DaZhen  Yin  CaiHua  Zhang  YingMei  Tian  LinJie  Li  Ting  Li  Dan  Ma  DaLong  Guo  YingLu  Wang  Ying 《科学通报(英文版)》2009,54(6):1050-1057
CKLF (chemokine-like factor)-like MARVEL (MAL and related proteins for vesicle trafficking and membrane link domain) transmembrane domain containing (CMTM) is a novel gene family. One member of this family, CMTM2, also named chemokine-like factor superfamily 2 (CKLFSF2), is expressed highly in the testis and moderately in the prostate, marrow and peripheral blood cells. However, the function of human CMTM2 remains unknown. Here, we found that CMTM2 was upregulated in 5α-dihydrotestosterone (DHT)-treated LNCaP cells. We investigated the relationship between CMTM2 and the androgen receptor. Our results showed that CMTM2 enhanced DHT-mediated androgen receptor (AR) transactivation and the expression of prostate specific antigen (PSA). We also observed that CMTM2 enhanced the AR protein level, which was reversed by silencing endogenous CMTM2 expression, which suggested that CMTM2 might play an important role in maintaining the AR protein level. We also found that CMTM2 suppressed Akt activation. A previous study showed that Akt could phosphorylate AR at Ser210 and Ser790 and lead to AR ubiquitylation and degradation as well as suppression of AR activity. Taken together, suppressing Akt activation and increasing the AR protein level might be one of the mechanisms for the CMTM2-mediated enhancement of AR transactivation. Supported by National High Technology Research and Development Program of China (Grant Nos. 2006AA02A305 and 2002BA711A01) and National Natural Science Foundation of China (Grant Nos. 30271203 and 30671907)  相似文献   
116.
117.
对近年来视黄素受体介导视黄素抗癌作用机理的研究进展作一综述,主要有:1)视黄素受体;2)视黄素受体与细胞生长;3)视黄素受体与孤生受体的的相关性;4)视黄素受体对AP-1活性的抑制作用;5)视黄素受体介导的信号转导途径。通过研究,对于探讨视黄素受体的功能、阐明视黄素的抗癌机理、合成更多的受体选择性视黄素具有重要的现实意义。  相似文献   
118.
利用分光光谱滴定法考察了以脱氧胆酸做spacer的钳形体1~4的识别性能,结果表明,该类分子钳可识别酚类化合物。  相似文献   
119.
IntroductionGonadotropin- releasing hormone ( Gn RH) ,whichis synthesized in the brain and secreted into theanterior pituitary,plays a central role in thecontrol of mammalian reproduction[1,2 ] .Gn RH andGn RH m RNA have been reported to exist in non-hypothalamic tissues such as ovary[3,4 ] ,breast[5] ,testes,and placenta[6] .The Gn RH binding siteand its m RNA have also been found inextrapituitary tissues,including gonads andplacenta[7] .These findings indicate the biologicalsignifican…  相似文献   
120.
In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of muscarinic receptor (muscarine) could induce stomatal opening, while the antagonists (atropine) could block stomatal opening induced by acetylcholine. Their effects can only be realized in medium containing Ca2+, but not in medium containing K+. The results tend to reveal that the muscarinic receptor is involved in acetylcholine-induced stomatal movement.  相似文献   
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