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1.
铜、汞、镉、六六六和对硫磷对食蚊鱼生长的影响 总被引:2,自引:0,他引:2
对2日龄的食蚊鱼仔鱼的急性毒性,96小时LC是:铜,0.28毫克/升;汞,0.58毫克/升;镉,10.2毫克/升;六六六(丙体),0.53毫克/升;对硫磷,0.3毫克/升。依据20天的生长数据求得的铜、镉和对硫磷的最大允许毒物浓度分别是0.015-0.030,0.005-0.010和0.0015-0.0030毫克/升,相应的应用系数分别为0.01。 相似文献
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芥菜型油菜原生质体再生成植株的研究 总被引:8,自引:1,他引:7
芥菜型油菜子叶和下胚轴原生质体在含0.5毫克/升NAA、0.5毫克/升2,4-D和1毫克/升BA的Nitsch培养基中发育成愈伤组织。“黄辣芥”子叶原生质体来源的愈伤组织在无生长素而含有3毫克/升BA或2毫克/升KIN的MS固体培养基上分化了芽;即使是低水平的生长素(0.05毫克/升NAA)也不利于芽的分化。当芽长到2—3厘米高时,将其从愈伤组织上切下,转移到不含细胞分裂素而有0.01—0.05毫克/升IAA的MS培养基上,很快长出根,从而得到完整的再生植株。 相似文献
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本工作研究了豆科植物紫云英的叶片及叶肉原生质体的培养。叶片培养实验表明,诱导愈伤组织的最适培养基为MS加1.0-2.0毫克/升2,4-D和0.25毫克/升KT;诱导根分化需加1.0—5.0毫克/升NAA和0.5毫克/升BA;而苗分化则以0—0.5毫克/升IAA和0.5毫克/升BA为好。高浓度的NAA有利于根分化而抑制茎芽形成;高浓度的IAA对根和芽分化都有抑制作用。叶肉原生质体分离和培养试验表明,紫云英叶肉原生质体的释放及其培养活力受叶龄、植株生理状态和酶浓度的影响。叶肉原生质体在改良的KM8P培养基中能分裂。用改良KM8细胞培养基定期稀释,可使分裂持续进行而得到细胞团。BA和2,4-D为诱导紫云英叶肉原生质体分裂所必需。其最佳组合激素为BA 0.21毫克/升和2,4-D 1.13毫克/升。葡萄糖作为渗透压稳定剂时,其浓度明显影响原生质体的存活率。弱光条件下培养比黑暗培养有利于叶肉原生质体分裂。由叶肉原生质体形成的愈伤组织能形成瘤状结构和根。 相似文献
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把β-蜕应激素〔1〕加入基本培养基中,观察对菊花叶外植体分化芽和潜伏腋芽生长的影响,发现0.05—0.3毫克/升的β-蜕皮激素以1:10的比例分别与0.5—3.0毫克/升的6-(艹卡)基瞟呤(6-BA)配合,使能叶块组织成愈伤组织并分化出不定芽,但不分化形成根;与α-萘乙酸(NAA0)配合则易形成根而不分化芽:0.5—4.0毫克/升的β-蜕皮激素与6-BA或NAA配合能促进潜伏腋芽萌发;0.25—4.0毫克/升的β-蜕皮激素能使“无根苗”生根形成完整植株。由上可见,β-昆虫蜕皮激素的作用主要和生长素类似。 相似文献
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《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1999,122(2):253-263
The accumulation of cadmium, copper and lead and their effects on aspartate and alanine aminotransferases in digestive gland, gills, foot and soft body in the clam Ruditapes philippinarum were examined. The animals were exposed to different concentrations: Cd (200–600 μg·l−1), Pb (350–700 μg·l−1) and Cu (10–20 μg·l−1) for 7 days. The highest concentrations were found in digestive gland for cadmium and copper, and in gills for lead, and the lowest values were observed in the foot. Aspartate aminotransferase activity (AST), in general, was not inhibited by cadmium, lead or copper during the exposure. Only in clams exposed to cadmium (600 μg·l−1, 7 days) and copper (20 μg·l−1, 5 days) were observed significant differences (P<0.05) in foot and gills, respectively, with respect to control. In the case of alanine aminotransferase activity (ALT), significant differences were observed for cadmium and lead in treated animals with respect to control. With regard to copper, a decrease in ALT was observed in gills and foot exposed to 20 μg·l−1. A significant correlation (P<0.05) was observed between ALT and metal accumulation for cadmium, copper and lead in gills. In the case of soft body, only cadmium and lead showed a significant correlation. In summary, R. philippinarum can be considered a bioindicator species for cadmium and lead accumulation and ALT could be useful as biomarker of sublethal stress for these metals in soft tissues and gills. Only gills can be considered an adequate target tissue for copper. 相似文献
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Postinductive actinomycin D effects on the concentrations of cadmium thionein, zinc thionein, and copper chelatin in rat liver 总被引:3,自引:0,他引:3
The time courses of induction in rat liver of copper chelatin by copper, cadmium thionein by cadmium, and zinc thionein by copper, cadmium, and zinc were monitorg metal were used in order to avoid toxic effects, being 5 mg zinc, 0.5 mg copper, and 0.25 mg cadmium per kg body weight. Peak times of induction and half times of decay observed were: copper chelatin (9 h, 8.6 h), cadmium thionein (18 h, 6.80 days), and zinc thionein (zinc rats, 18 h, 10.1 h; copper rats, 9 h, 18.2 h; cadmium rats, 24 h, 4.53 days). Administration of actinomycin D (1 mg per kg body weight) at the peak times of induction of the various proteins had no effect on the concentrations of chelatin or cadmium thionein observed up to 24 hours later, but in the case of zinc thionein, induced by zinc, copper, or cadmium, elevated concentrations were observed up to 23 h after administration of the drug. Such behavior is reminiscent of superinduction previously seen with other proteins and enzymes. We postulate that the intracellular concentration of free zinc in liver is of fundamental importance in the induction of zinc thionein, and this can be distributed by exogenous copper or cadmium resulting in the induction of synthesis of zinc thionein. 相似文献
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This study reports age-related changes in 7 element (iron, copper, zinc, manganese, mercury, cadmium and lead) concentrations in the liver, kidney and brain of male and female Sprague-Dawley rats from 1 to 364 days of age. Atomic absorption spectrometry was used for the measurements. Copper, mercury and cadmium in the male and female kidneys increased from weaning until 127 days of age, as did iron concentrations in the female liver and kidney. After 127 days, especially, the copper concentration in the female kidney and cadmium concentration in the male and female kidney increased further. Consistent and statistically significant (P less than 0.05) sex differences in element concentrations were found for three elements (iron, copper and zinc). Except for the zinc concentration in the liver from 50 to 72 days, iron (in liver and kidney), zinc (in kidney) and copper (in liver, kidney and brain) concentrations in female rats during the adult stage, were all higher than those of male rats. Isolated differences for other elements (manganese, mercury and cadmium) were also found. The data will be helpful when setting up long-term animal investigations of the biological effect of elements. 相似文献
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Male external genitalia show structural variations among species. Androgenic hormones are essential for the morphological specification of male type copulatory organs, while little is known about the developmental mechanisms of such secondary sexual characters. Western mosquitofish Gambusia affinis may offer a clue to the sexual differentiation researches, because they show a prominent masculine sexual character for appendage development, anal fin to gonopodium (GP) transition, and its formation could be induced in early juvenile fry by exogenously supplied androgens. We show that GP development is promoted by androgen dependent augmentation of sonic hedgehog (Shh) expression. Two AR cDNAs were cloned and identified as ARalpha and ARbeta from western mosquitofish. Both ARs were predominantly expressed in the distal region of outgrowing anal fin rays. Exposure of fry to androgen caused anal fin outgrowth concomitant with the Shh induction in the distal anal fin ray epithelium. When AR signaling was inhibited by its antagonist flutamide in fry, the initial induction of the Shh was suppressed accompanying retarded anal fin outgrowth. Similar suppression of anal fin outgrowth was induced by treatment with cyclopamine, an inhibitor of Shh signaling. These observations indicate that androgen dependent Shh expression is required for anal fin outgrowth leading to the formation of a genital appendage, the GP in teleost fishes. Androgen-induced GP formation may provide insights into the expression mechanism regulating the specification of sexual features in vertebrates. 相似文献
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巨须裂腹鱼(Schizothorax macropogon)隶属裂腹鱼亚科, 裂腹鱼属, 是西藏特有经济鱼类, 因过度捕捞, 其种群数量和分布面积下降, 在2009年中国红色名录评为“濒危”等级。研究通过研究巨须裂腹鱼早期发育特征, 旨在为该鱼的科学养护提供技术支撑。结果表明: 巨须裂腹鱼受精卵直径3.0—3.2 mm, 遇水开始具有微黏性, 随后脱黏, 经过准备卵裂阶段、卵裂阶段、囊胚阶段、原肠胚阶段、神经胚阶段、器官分化阶段、 孵化阶段, 在水温10℃的条件下, 经过460.67h孵化出来。初孵仔鱼体长9.9—1.1 mm, 心率48—50次/min, 鳃盖骨清晰可见, 下颌原基、尾鳍下骨原基可见。第2天鼻凹出现; 第3天肝胰脏原基出现; 第4天鳃耙、肩带原基出现; 第6天仔鱼上下颌开始张合; 第7天心血管分化结束, 仔鱼开始进入混合营养期; 第14天鳔一室和体侧色素带形成; 第26天肋骨原基出现; 第35天鳔二室出现, 卵黄囊耗尽; 第63天背鳍分化结束; 第83天臀鳍分化结束。巨须裂腹鱼胚胎具有独特的发育时序: 体节的出现先于胚孔封闭, 是对高原环境的一种适应和进化。 相似文献
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研究了离心力对间隙水化合物浓度的影响.将腐殖质掺入东湖沉积物样品,按泥:水=1:4(体积)比室温下静置30d,随后掺入铜,泥:水=1:4(体积)比静置10d,得到总有机碳含量在1.47%-.72%、铜含量在120-2700mg/kg(干重)的试验沉积物样品,用离心法制备沉积物中的间隙水.离心参数为3000r/min、200r/min、9000r/min、1000r/min和12000r/min,4 ℃下离心20min.间隙水中化合物浓度分析表明,随离心力升高,间隙水中铜、铁、总有机碳(TOC)含量逐渐降低,钙的含量略有增加,而锰的含量不受离心力变化的影响.根据上述分析结果,确定在腐殖质对沉积物中铜的毒性影响研究中,制备沉积物间隙水的适宜离心条件为:12000r/min、4℃下离心20min.
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应用食蚊鱼(Gambusia affinis)的卵黄蛋白原(VTGa)基因和雌/雄激素受体(ERa/ARa)基因转录水平为指标, 评价广东东莞寒溪河受雌/雄激素物质污染的现状。结果显示, 与对照点从化流溪河(LX)相比, 寒溪河松山湖(SM)、杨屋村(YW)、横沥镇(HL)、樟村污水处理厂上游(ZU)和樟村污水处理厂下游(ZC)各采样点雄性成年食蚊鱼肝脏中的VTG转录水平都具有显著或极显著水平的升高(p0.05和p0.001), 分别为7.67、169.43、148.69、152.01和98.12倍; 而较之对照点, 雄鱼臀鳍的雌激素受体ER转录水平仅HL位点有显著性升高(p0.05), 其余位点则不明显(p0.05)。此外, 寒溪河SM、YW、HL、ZU和ZC各采样点雌鱼臀鳍雄激素受体AR转录水平分别是对照点从化流溪河(LX)的1.21、0.82、0.34、0.41和0.89倍, 但是只有HL和ZU点有显著性减小(p0.05), 其余各点的变化差异不显著(p0.05)。研究结果显示, 生活在东莞寒溪河中的食蚊鱼受雌/雄激素物质干扰明显, 普遍出现显著的雌激素效应, 表明寒溪河水体受雌激素物质污染更严重。此外证明, 鱼类肝脏VTGa基因相对于臀鳍ERa/ARa基因转录水平更适合作为监测水体环境雌/雄激素物质的生物标志物。
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为研究钙对摄食高铜饲料的大黄鱼幼鱼生长性能、抗氧化酶类及脂代谢酶类活性的影响,研究采用22双因子实验设计,配制了4组实验饲料,共包含2个铜水平(4和24 mg/kg)和2个钙水平(0.5%和3%),分别命名为: -Cu-Ca、+Cu-Ca、-Cu+Ca和+Cu+Ca,饲喂大黄鱼幼鱼[(4.050.31) g]10周,每个处理组设置3个重复。结果表明,高铜组(+Cu-Ca和+Cu+Ca)实验鱼的存活率、终末体质量和增重率显著低于低铜组(-Cu-Ca和-Cu+Ca)(P0.05); 高铜组实验鱼肝脏和肌肉中的铜含量显著高于低铜组,而高钙组(-Cu+Ca和+Cu+Ca)实验鱼肌肉中的铜含量却显著低于低钙组(-Cu-Ca和+Cu-Ca)(P0.05); 高铜组实验鱼肝脏中的糖原含量显著低于低铜组(P0.05); 实验鱼肝脏中的超氧化物歧化酶、过氧化物酶、谷胱甘肽过氧化物酶、6-磷酸葡糖酸脱氢酶、异柠檬酸脱氢酶和脂肪酸合成酶活性,高铜组显著低于低铜组,而高钙组却显著高于低钙组,但硫代巴比妥酸反应物含量和脂蛋白脂肪酶活性正好相反(P0.05); 饲料中铜和钙的交互作用显著影响了实验鱼肌肉中的铜含量、硫代巴比妥酸反应物含量、6-磷酸葡糖酸脱氢酶、脂肪酸合成酶和脂蛋白脂肪酶活性(P0.05)。研究表明,钙能够缓解摄食高铜饲料对大黄鱼幼鱼造成的伤害。 相似文献
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Carbonic anhydrase (CA) enzyme was purified from rainbow trout brain by Sepharose-4B-L: -tyrosine-sulfanilamide affinity chromatography. The enzyme was obtained with a specific activity of 2,275 EU mg(-1) and a yield of 22.5%. The sample obtained from the affinity column was used for kinetic properties and inhibition studies. Both optimum and stable pH were found as 9.0 in 1 M Tris-SO(4) at 4 degrees C, respectively. To check the purity and subunit molecular weight of enzyme, sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis was performed, and MW was found as approximately 29.0 kDa. The molecular weight of native enzyme was estimated to be approximately 27.3 kDa by gel filtration chromatography. The purified enzyme had apparent K (m),V (max), and k (cat) as follows: 0.92 mM, 0.207 micromol.min(-1) and 43.6 s(-1) for p-nitrophenylacetate. The inhibitory effects of Co(II), Cu(II), Zn(II), Ag(I), and Cd(II) on CA enzyme activity were determined using the esterase method under in vitro conditions at low concentrations of the corresponding metals. The obtained IC(50) values, which cause 50% inhibition on in vitro enzyme activity, were 0.05, 30, 0.31, 159, and 82.5 mM for cobalt, copper, zinc, silver, and cadmium, respectively. K ( i ) values were also calculated from Linewaever-Burk plots for these substances as 0.014, 27.68, 2.15, 193.86, and 94.18 for cobalt, copper, zinc, silver, and cadmium, respectively; it was determined that cobalt, silver and cadmium inhibited the enzyme competitively, copper inhibited noncompetitively while zinc inhibited the enzyme uncompetitively. 相似文献
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Summary The influence of heavy metal additions on availability and uptake of cadmium, lead, zinc, copper, manganese and iron by oat was studied. The experiments were carried out as pot experiments using sandy loam, sandy soil and organic soil. Selective extractants were used to remove metals held in different soil fractions.Lead and copper were preferently bound by organics and oxides, zinc by oxides and inorganics, and cadmium by inorganics and organics.Addition of cadmium to the soils resulted in higher cadmium concentrations in all plant parts but lower concentrations of lead, zinc, copper, manganese and iron, and the accumulation indexes of these metals were also lower when cadmium was added to the soil.Addition of cadmium plus lead, zinc and copper resulted in higher cadmium concentrations in leaves and straw of plants grown in sandy loam and sandy soil, but lower concentrations when plants were grown in organic soil as compared with the results when cadmium was added separately. The transfer of cadmium, lead, zinc and copper from soil to plant was greatest from sandy soil, and zinc and cadmium were more mobile in the plant than were lead and copper.Cadmium concentrations in leaves correlated significantly with CaCl2 and CH3COOH extractions in sandy loam and sandy soil and with CH3COOH extractions in organic soil.Generally, the total metal uptake was lowest from organic soil. 相似文献