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1α,2 5-双羟维生素 D3 [1 α,2 5(OH) 2 D3 ]作用于靶细胞后产生 2种不同的信号传导系统 :基因效应和非基因效应。前者是指 1α,2 5(OH) 2 D3 与维生素 D核受体 (n VDR)结合 ,n VDR再与视黄酸 X受体 (RXR)发生异二聚化反应 ,在转录因子 (TF)的作用下 ,促使靶基因转录。后者是指 1 α,2 5(OH) 2 D3 与维生素 D膜受体 (m VDR)结合 ,随之引发一系列信号传导 ,促使细胞膜上的 Ca2 -通道迅速打开。探讨 1α,2 5(OH) 2 D3 的作用机制有利于开发治疗维生素 D内分泌系统疾病的新药。本文就目前有关 1 α,2 5(OH) 2 D3 作用于靶细胞的机制的研究成果进行综述。 相似文献
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中国对虾酸性和碱性磷酸酶的特性研究 总被引：18，自引：1，他引：18
磷酸酶,又称正磷酸单酯水解酶,是一种能催化各种含磷化合物水解的酶类,根据它们起催化作用的最适pH特性,又可分为酸性磷酸酶(EC 3.1.32)和碱性磷酸酶(EC3.1.31)两类。磷酸酶具有非常重要的生理功能,它广泛存在于各种动物体内,是动物体内重要的解毒体系,并且在动物机体的骨化过程及在磷化物和其它一些营养物质的消化、吸收和转运过程中都起着重要作用。此外,通过催化磷蛋白的水解,磷酸酶在细胞调节过程中也具有一定作用。尽管磷酸酶的研究有很久的历史,但绝大多数的研究几乎都集中在陆生的高等脊椎动物哺乳类身上。在无脊椎动物体中这方面研究的很少,而有关甲壳类动物磷酸酶的研究文献几乎没有。 相似文献
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细胞核的雌激素受体(ER)是参与调节脊椎动物发育和繁殖的转录因子,哺乳动物具有两种类型的ER(ER-α和ER-β),它们一旦与配体结合就能够形成二聚体,和其他转录激活因子相互作用,参与靶基因调节[1].目前,在鱼类中发现3种ER类型,即ER-α,ER-β和ER-γ[2~4],这说明鱼类ER生理功能比高等动物复杂,但对每种ER的功能研究较少.雄激素在脊椎动物(包括鱼类)的性别分化和性腺发育过程中起着十分重要的作用,一般认为这种作用是通过雄激素受体(AR)介导的[5].AR属于配体活性转录因子,是核受体家族的一员[6]. 相似文献
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目的：观察补肾活血中药联合维生素D对多囊卵巢综合征（PCOS）不孕患者内分泌及抗氧化的作用。方法：选取PCOS不孕患者90 例作为研究对象,以随机数字表法分为中西医结合组、中药组、西药组,每组各30 例。中西医结合组给予补肾活血中药联合维生素D辅助干预治疗,中药组仅予补肾活血中药治疗,西药组给予克罗米芬治疗。将3个月经周期定为1个疗程。治疗1～2个疗程后比较3组患者排卵率、妊娠率、性激素［包括雌二醇（E2）、促卵泡生成素（FSH）、促黄体生成素（LH）、雄激素（T）］和25-羟维生素D（25OHD）、丙二醛（MDA）、超氧化物歧化酶（SOD）水平。结果：中西医结合组及中药组均可有效提高E22及25OHD水平,降低T及MDA水平,对FSH、LH有调节性作用,可进一步提高妊娠率,且在调节内分泌方面中西医结合组较中药组、西药组疗效更佳（P＜0.05）。结论：补肾活血中药联合维生素D辅助治疗PCOS不孕患者,可以明显改善内分泌代谢及氧化应激状态,提高临床妊娠率。 相似文献
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胰岛素(Insulin, Ins)作为动物体内最保守的小分子蛋白,是调控血糖、脂肪和蛋白质代谢的重要激素,同时也对卵生动物的卵黄合成发挥着重要作用,但在鱼类中研究相对较少。为探讨银鲳胰岛素对卵黄合成的影响,从转录组数据中获得了银鲳3个胰岛素insulin(ins)、insulin-like(ins-like)和insulin-2(ins-2)基因全长cDNA序列。序列分析表明,银鲳3个胰岛素基因的氨基酸序列具有胰岛素基因的典型特征,包含NH-2端分泌的信号肽和由B链、C链和A链组成的IIGF。系统进化树分析表明,哺乳类ins单独为一簇,鱼类ins和ins-2成一簇及鱼类ins-like单独成一簇。组织表达特征分析表明,银鲳胰岛素家族3个基因ins、ins-2和ins-like在各个组织中广泛表达,但是不同组织的3个基因表达水平不相同。对不同发育阶段的银鲳肝脏和卵巢组织中3个胰岛素基因和3个卵黄蛋白原(vitellogenin, vtg)基因的表达量进行了分析,结果显示,所有银鲳ins和vtg基因在肝脏和卵巢中的表达趋势一致,从Ⅱ期至Ⅳ期肝脏和卵巢中逐渐升高,并在Ⅳ期达到最高值,从Ⅳ期至... 相似文献
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荷兰鲱鱼节鲱鱼多生活在北太平洋和北大西洋温带浅水中,春天,它们经常成群地聚集在欧洲和北美洲的海岸附近。鲱鱼是重要的经济鱼类,体内多油,并含有丰富的合成维生素D的原料。 相似文献
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3-(3′-羟基)丁基苯酞是丁苯酞在体内的代谢产物,具有多种药理作用,可以作为一种新的活性成分应用于药物开发中。本文以甘氨酸、甲硫氨酸和亮氨酸为起始原料,经过Boc保护,再与3-(3′-羟基)丁基苯酞进行缩合,脱保护3步反应合成了3-(3′-羟基)丁基苯酞的氨基酸酯。以期提高水溶性和改善药代动力学性质,获得3-(3′-羟基)丁基苯酞的前药。 相似文献
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《海洋湖沼通报》2021,(3)
广东惠州海域是粤港澳大湾区生态安全屏障的关键节点。本文分析了2018年夏季惠州20种海洋鱼类体内Cu、Pb、Cd含量,利用单因子污染指数(SFI)进行了重金属污染水平评价,探讨了栖息水层、食性对鱼类体内重金属富集的影响。结果显示,(1)2018年夏季惠州海域鱼类体内重金属含量大小顺序与春季相同,皆为CuPbCd;夏季鱼类体内Cd含量显著高于春季,其与海水、沉积物重金属的季节变化无明显响应关系。(2)栖息水层方面,中上层鱼类体内Cu、Cd含量平均值高于中下层及底层鱼类,Pb含量反之;鱼类体内Cu含量差异显著,说明生境中重金属生物可利用性和鱼种类对鱼体内重金属富集有重要影响。(3)杂食性鱼类体内Cu和Pb较高,底栖动物食性鱼类容易富集Cd,反映了鱼类选择性吸收重金属元素;方差分析结果显示,摄食行为并未导致鱼类体内Cu、Pb、Cd元素富集。(4)鱼类体内Cu与Pb的Pearson相关分析结果为显著正相关,反映其具有同源性。(5)SFI平均值显示,夏季惠州海洋鱼类体内重金属污染程度高于春季;夏季鱼类体内Cu含量为正常水平,Pb整体为轻度污染,Cd为重度污染。(6)参照《无公害食品水产品中有毒有害物质限量》(NY 5073-2006)和WHO/FAO标准,2018年夏季鱼类体内Cd含量分别超标70%和20%,需引起关注。 相似文献
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在水温11.0～14.0℃条件下,将平均体质量2.29 g的幼刺参(Apostichopus japonicus)随机放入39个容积50 L塑料水槽中,投喂以玉米蛋白为蛋白源,分别添加0、500、1 000、2 000和4 000 mg/kg V_C-2-三聚磷酸酯(L-ascorby1-2-polyphosphate, LAPP)、V_C-棕榈酸酯(L-ascorby1 palmitate, LAP)和V_C -磷酸酯镁(L-ascorby1-2-monophosphate-magnesium, APM)的13种饲料.90 d的饲养情况表明,摄食添加V_C饲料的刺参的生长、蛋白质效率均显著高于摄食未添加V_C的幼参(P＜0.05).摄食添加LAPP饲料幼参的特殊生长率最高(0.21%/d),添加LAP(0.17%/d)的次之,添加APM(0.15%/d)的最低,分别比对照组(0.12%/d)高75.00%、41.67%和25.00%.摄食添加LAPP饲料幼参的平均蛋白质效率最高(12.57%),摄食添加LAP饲料的(7.76%)次之,摄食添加APM(6.86%)的最低,分别比对照组(5.52%)高127.72%、40.58%和24.28%.在3种剂型V_C组中,饲料系数由低到高依次为:LAPP＜LAP＜APM.饲料中LAPP、APM和LAP的添加量为2 000～2 500 mg/kg、1 000～1 500 mg/kg和2 000～3 125 mg/kg时,幼刺参对饲料蛋白的表观消化率最高,生长最快,饲料系数最低. 相似文献
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An extensive trial to examine physiological and biochemical changes in perch (Perca fluviatilis) inhabiting coastal waters polluted by bleached kraft mill effluents has been carried out. The results from this investigation show profound effects of bleached kraft mill effluents on several fundamental biochemical and physiological functions on four different sampling occasions. Typical symptoms in perch from the polluted areas were reduced gonad growth, enlarged liver, and very strong induction of certain cytochrome P-450-dependent activities. Elevated content of ascorbic acid in liver tissue and strongly affected carbohydrate metabolism show that the effluent causes metabolic disorders. Marked effects on the white blood cell pattern indicate a suppressed immune defence. Alterations in the red blood cell status and the ion balance suggest an impaired gill function. This extensive symptom picture is strengthened by the relatively good agreement with the effects previously observed in fish exposed to bleached kraft mill effluents (BKME) in the laboratory.1–3 相似文献
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神经肽是神经系统最大、最多样化的一类信息分子,可调节动物的各种生理过程和行为。相较于脊椎动物和原口无脊椎动物,棘皮动物神经肽的研究起步较晚,而棘皮动物关键的分类地位和独特的生物学特征为其神经肽信号系统功能的研究提供了特殊背景。本文从神经肽分子的自身特性出发,对棘皮动物神经肽的作用方式、鉴定方法、功能调节及受体发掘等相关研究成果进行了综述,并对其未来的研究进行了展望。以期进一步解析神经肽在棘皮动物特殊生理行为调控中的作用机制,为棘皮动物中经济物种的高效绿色增养殖提供理论支撑。 相似文献
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The biotransformation of xenobiotics by microsomal cytochromes P450 is known to be pivotal in the effects of some compounds, and thought to be so for many. A knowledge of CYP gene diversity and CYP function and regulation in aquatic species is pursued, expecting that it will disclose mechanisms, allow predictions regarding species differences in susceptibility, and provide markers for exposure to xenobiotics. As well, it is hoped that such knowledge will provide clues to CYP endogenous functions, and to the origin and functional significance of CYP gene diversity. The knowledge of CYP in marine and other aquatic species is expanding rapidly. The diversity of CYP genes in non-mammalian vertebrates may approximate that in mammals. At present, cloning studies have identified members of gene families 1 to 4 have been cloned from one or more fish species. Where known, the gene structures of fish CYP genes are like those of mammalian homologues. Only one CYP1A gene has been identified in most fish species examined. Fish CYP1As, including multiple forms from recent divergence in some genera, have structural and catalytic properties more like CYP1A1, but also have properties that are 1A2-like, consistent with fish CYP1As representing the CYP ancestral to both CYP1A1 and CYP1A2. A number of genes cloned from several species have been classified in the 3A subfamily. Fish CYP3As catalyze steroid 6β-hydroxylase, and have other properties consistent with mammalian 3As. Recently identified CYP4 genes classify to novel subfamilies but apparently are homologues of mammalian CYP4 genes, and may act on similar substrates. The greatest diversity of fish CYP genes is in family 2; there are now six fish CYP2 subfamilies known. Four of these are novel subfamilies, although cladistic analysis suggests distinct relationships to mammalian CYP2 subfamilies. Heterologous expression and characterization of some of these CYP have identified similar functions among genes in different subfamilies. For example, fish CYP2Ns and CYP2Ps are related to mammalian CYP2Js, and CYP2P3 and CYP2J2 have strikingly similar functions as fatty acid epoxygenases and hydroxylases, with nearly identical regio- and enantioselectivity for metabolism of arachidonic acid. In addition to sequence and catalytic similarities, there also are indications that CYP regulation, tissue and cellular localization are similar between fish and mammals. Yet even in cases where orthology is strongly suggested, e.g. CYP1A, there appear to be taxonomic differences in active site structure suggesting potential differences in involvement of CYP1A in toxicity. In contrast to fish, CYP diversity and functions in aquatic invertebrates are poorly known. Investigators have identified novel gene families and subfamilies in crustaceans (CYP2L; CYP45), molluscs (CYP30, CYP10) and sponges (CYP38). CYP4C genes occur in crustaceans, molluscs and echinoderms, and a new subfamily (CYP4Y) in molluscs. The future? There is no doubt that new CYP will continue to be discovered in non-mammalian vertebrates; some (e.g. CYP51) can be predicted confidently. And, there is no doubt that the numbers known in invertebrates will expand greatly. In insects and C. elegans the numbers are very high, and even slime molds have 18 CYP genes. It is virtually certain that CYP genes with unique functions will be discovered. While the knowledge of CYP genes is increasing, knowledge of CYP function and regulation lag well behind. Technical approaches to speed the aquisition of such knowledge are available. The information will be essential to discern the role that CYP play in the disposition and toxicity of xenobiotics, during development as well as in adults. Yet, when such data are in hand, we may have to face the paucity of information on the diversity, function and regulation other enzymes, notably the glutathione S-transferases, glucuronyl transferases and sulfotransferases, in aquatic species. Discerning orthologous relationships among CYP genes, as well as those for phase II enzymes, could highlight gene lineages associated with conserved and endogenous functions. Understanding CYP endogenous functions, as well as their metabolism of xenobiotics, may reveal fully the ways that chemicals cause toxicity. [Support: Sea Grant NA46RG0470-R/P61, EPA R-829890, NIH ES07381]. 相似文献
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本研究以黄颡鱼(Pelteobagrus fulvidraco)为试验对象,设计两种饲料:鱼粉组和无鱼粉组,在池塘网箱中投喂70 d,研究其生长性能和肝胰脏转录组表达的差异。同鱼粉组相比,无鱼粉组黄颡鱼特定生长率下降了30.25%(P0.05),饲料系数显著增加了83.94%(P0.05),全鱼脂肪含量显著下降(P0.05),血清甘油三酯含量显著下降(P0.05),血清转氨酶活力显著增加(P0.05)。肝胰脏转录组结果显示,总计有12 020个基因差异表达,其中差异表达上调的基因有5 020个、差异表达下调的基因有7 000个。同鱼粉组相比,无鱼粉组分别有1 013个基因表达显著上调、2749基因表达显著下调(P0.05)。将组间具有差异表达的基因进行GO Term、KEGG pathway分类,结果显示:无鱼粉组的肝胰脏细胞组成、细胞生物过程、细胞分子功能等绝大多数基因差异表达下调,提示肝胰脏的细胞组织结构和功能受到很大的影响;KEGG通路富集到15个显著差异代谢通路。本研究结果表明,日粮中鱼粉可能含有某些生理活性物质,这些物质以神经分泌、激素调控、代谢信号通路等为作用靶点,通过对这些代谢信号通路的调节,对鱼的整体生理代谢强度、细胞结构与功能、生理健康状态等产生明显积极促进影响。缺乏这些物质则会造成黄颡鱼生长性能下降、部分器官组织细胞(肝细胞、神经轴突)受到损伤、鱼体抗应激能力和免疫防御能力下降。 相似文献
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麻痹性贝类毒素（paralytic shellfish toxins,PSTs）能够导致贝类、鱼类等海洋生物染毒或死亡,危害海洋生态安全及人类健康。其中,贻贝具有强蓄积性特点,在国外可作为PSTs的指示性生物。近年来,我国因食用贻贝造成多起PSTs中毒事件成为安全关注重点,因此急需弄清其风险形成机理。本文通过综述我国近海贻贝等贝类中PSTs的风险程度、贻贝对不同产毒藻来源的PSTs的蓄积作用,分析环境因子对于蓄积代谢的影响,深入挖掘贻贝蓄积代谢特异性。进而聚焦贻贝代谢阶段的表达调控过程、影响因素、转化作用及方式等。未来应侧重于摸清我国目标区域贻贝等海洋贝类中PSTs基础风险规律和变化过程,并据此建立区域性PSTs风险防控技术,提高我国贻贝中PSTs风险的主动防控能力,对于保障消费者健康和海洋生态安全具有积极意义。 相似文献
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本试验旨在研究饲料维生素C对美国红鱼(Sciaenops ocellatus)组织中的NO含量、NOS活力和NOS基因表达的影响。采用单因子试验设计,将360尾平均体重为(147.28±7.69)g的美国红鱼随机分为6个处理,每个处理设3个重复,每个重复20尾,分别饲喂6种不同维生素C水平(0、49.3、98.9、197.5、396.4和1989.8mg/kg)的等氮等能饲料,进行为期8周的生长试验。结果表明:头肾、肝、肠、胸腺NO含量随着饲料维生素C含量增加有显著增加;脾中各组NO含量无显著性差异;脑中NO含量C0组与其它各组相比有显著性差异。头肾、肝、胸腺NOS活力随着饲料维生素C含量增加有显著增加;脾和肠中各组NOS活力无显著性差异;脑中NOS活力C396.4组与其它各组相比有显著性差异。脑中各组nNOS基因mRNA的表达含量无显著性差异;在饲料维生素C含量达到1989.8mg/kg时,其它各组织内的nNOS基因mRNA的表达量最高。综上所述,饲料中添加适当维生素C对美国红鱼组织中的NO含量、NOS活力和nNOS基因mRNA的表达有显著影响。 相似文献
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Pristane (2,6,10,14 -tetramethylpentadecane) occurs ubiquitously in the marine environment. This hydrocarbon may be of biogenic or petrogenic origin.1 Recently it has been shown that residual amounts of this branched alkane increased in marine organisms after an oil spill.2,3 The lack of data on the fate of pristane in fish, added with the fact that this compound was considered by some authors as a non-metabolisable substance in vertebrates, including man,4 led us to investigate the capability of fish to metabolise pristane. In this study, urinary and fecal excretion, tissue distribution and metabolism of 3H-pristane were analysed in Salmo gairdneri R. after a single intragastric dose. In addition to unchanged hydrocarbon, various labelled compounds have been isolated and identified in liver, bile, faeces, urine and surrounding water, demonstrating that pristane was first oxidised to alcohols (pristanol and pristane-diol) and to acid (pristanic acid). The elimination of these compounds occurred in the form of conjugated products (primarily glucuronides) as well as free metabolites. 相似文献
19.
Marco A. Lardies José Luis Muñoz Kurt A. Paschke Francisco Bozinovic 《Marine Ecology》2011,32(1):42-51
The colonisation of the terrestrial environment by crustaceans is more apparent in tropical latitudes because of the high diversity of semi‐terrestrial and terrestrial crabs. However, in temperate regions there are also great numbers of crustaceans that inhabit ecological niches at the water–air interface. Grapsidae crabs (Decopoda) are especially important in studies of water‐to‐land transition as the family contains species occupying the intertidal and adjacent regions. A way to evaluate the ability of intertidal invertebrates to breathe air is to measure the aerial/aquatic oxygen consumption ratio. The objective of this study was to test the effect of thermal variation on the aquatic and aerial metabolism. We selected as study model the decopoda crab Cyclograpsus cinereus Dana and utilised five populations of the species spread over 2000 km along the Chilean coast. To determine the compensation capacity in respiration with respect to latitude, we evaluated metabolic rate at the same temperature in a common garden design in the laboratory, to examine the extent to which variation in crab physiology is environmentally determined. Whereas in our study, mb (body mass) varied significantly with latitude, the difference in mass‐independent metabolism both in air and water persisted, indicating that observed differences in MR (Metabolic Rate) were not an effect of differences in body size. We demonstrated that C. cinereus is able to breath oxygen from air and water as expected for an amphibious crab. Almost all the studied populations of C. cinereus show a aerial/aquatic metabolism ratio near 1. The pattern found indicates an increase in metabolic rate, both aerial and aquatic, in low latitudes and therefore does not support the latitudinal compensation hypothesis for temperate habitats. Finally, these kinds of studies are required to make the necessary link between ecological physiology and macroecology and to help develop a global understanding of organismal function in marine systems. 相似文献
20.
长江航道水下地形三维可视化研究 总被引：1，自引：1，他引：0
三维地形可视化技术是现代地理信息技术的研究热点，广泛应用于地理信息的各个领域。通过长江中游太平口水道水下地形的三维建模，阐述了三维地形可视化技术在长江航道测绘领域的应用与发展，通过实例介绍了航道三维立体可视化图的制作过程。 相似文献