双链RNA病毒诱导的牙鲆胚胎细胞差减cDNA文库的构建

以紫外线灭活的dsRNA病毒草鱼出血病病毒(GCHV)诱导和模拟诱导的牙鲆胚胎细胞为材料,利用抑制性差减杂交(SSH)技术,成功构建了双链RNA病毒诱导的牙鲆胚胎细胞(FEC)差减cDNA文库。以管家基因αtub lin作为差减指标,经检测,该文库差减效率达210倍,表明经病毒诱导后某些差异表达基因也得到了相应倍数的富集。将获得的cDNA片段连接到pGEM T载体,PCR检测显示差减片段在250bp~2 000bp之间。该差减cDNA文库的构建为从分子水平研究牙鲆培养细胞对dsRNA病毒的免疫反应、以及进

稀有鮈鲫与其他模式实验鱼类基因组大小的比较

国家自然科学基金项目 ( 30 2 710 11); 淡水生态与生物技术国家重点实验室开放课题

CO_2浓度对中肋骨条藻的光合无机碳吸收和胞外碳酸酐酶活性的影响

为探讨低光照(30 μmol·m-2·s-1)和高光照(210 μmol·m-2·s-1)条件下海水CO2浓度变化对海产硅藻中肋骨条藻(Skeletonema costatum)的生理影响,对该藻生长及其光合CO2吸收和胞外碳酸酐酶(CAext)活性进行了测定,结果表明,在低光条件下,CO2浓度变化(4～31μmol/L CO2)对该藻的生长和净光合速率的影响比高光条件大.CAext在12和31μmol/L CO2时没有检测出活性;但在4 μmol/L CO2时则有明显活性,且其高光条件下的活性是低光条件

氯氰菊酯对大型溞的毒性研究

研究了农药氯氰菊酯对大型氵蚤的毒性效应 ,结果显示 :氯氰菊酯对大型氵蚤有明显的毒性作用 ,其 2 4h-LC50 为 4.81 mg/L,实验毒性为中级 .同时也研究了国际标准毒物重铬酸钾对大型氵蚤的毒性为 2 4h-LC50 为 0 .3 8mg/L,表明该大型氵蚤对毒物较为敏感 .最后讨论了实验条件对大型氵蚤2 4h-LC50 的影响

S7核糖体蛋白基因序列变异及其在低等鲤科鱼类中的系统发育意义

鲤科是世界鱼类中最大的科,有210余属2010种.为研究其系统发育关系需要筛选合适的DNA标记.将S7核糖体蛋白基因用作遗传标记进行鲤科鱼类的系统发育分析.通过PCR方法,扩增了长度为602bp的胭脂鱼以及长度为655～859bp的16种鲤科鱼类的S7基因内含子1序列.序列排列得到925个排列位点,其中信息位点499个,占全部位点的54％.结果表明,鲤科鱼类S7基因内含子1序列具有丰富的信息位点,并且在亲缘关系不同的物种间存在显著的序列差异.基于S7基因内含子1序列的NJ（neighbor-joining

水体富营养化对大型底栖动物群落结构及多样性的影响

在武汉东湖营养水平不同的四个湖区 ,对大型底栖动物的群落结构和物种多样性进行周年研究。大型底栖动物的物种多样性与营养水平呈相反趋势 ,富营养化导致多样性明显降低。研究还表明 ,霍甫水丝蚓的密度与水体营养水平呈正相关系 ,在超富营养水体中其密度最高 ,年平均 350 2ind ./m2 ,最高可达 1 0 52 4ind ./m2 ,这与其能忍受由于富营养导致的低氧环境有关 ;而在中营养水体中平均密度仅 2 7ind ./m2 。首次讨论了中国长足摇蚊与水体营养水平的关系 ,研究结果显示 ,中国长足摇蚊应属

我国某厂石墨电极废渣中二噁英的指纹特征

研究发现我国氯碱工业中由于采用石墨电极，产生的固体废渣中含有大量二噁英，其总浓度高达 ３７８．８５μｇ／ｋｇ，二噁英各组异构体浓度指纹的特征表现为以四至八氯代的二苯并呋喃（ＰＣＤＦｓ）为主，其中２，３，７，８位氯取代ＰＣＤＦｓ占废渣中总ＰＣＤＦｓ的８０ ％以上，而多氯代二苯并二噁英（ＰＣＤＤｓ）的浓度仅处于０．０１５ μｇ／ｋｇ水平．根据二噁英国际毒性当量因子（Ｉ－ＴＥＦ），计算出该电解废渣的毒性当量（Ｉ－ＴＥＱ）值为 ２１．６５μｇ／ｋｇ，我国电解废渣中二噁英的这种典型的“氯碱指纹”，在该氯碱工业废水排

人工四倍体鲤鲫的产生

在人工诱导的复合三倍体鲤鱼成熟个体中有极个别个体产出的卵既保留了原有的3套染色体,又能与一套外来精核融合产生四倍体。1997年人工产生的8000多尾鲤鲫四倍体鱼经细胞遗传学研究分析鉴定,结果所有的个体都有4套染色体组,染色体数目在185～210之间,众数为200,四倍体比率为100％。这表明人工复合三倍体鲤鱼的生殖方式十分独特,绝大部分个体的成熟卵可借助于外来精子的激动进行自然雌核发育;而有极个别个体的成熟卵能与外来精子融合产生四倍体个体。四倍体鲤鲫的形态特征像鲫鱼。

微型生态系统中浮游动物正磷酸盐排泄率的估算

在考查罗非鱼或鲢、鳙下行影响的微型生态系统实验后期，对其唯一的浮游动物──大型的特定正磷酸盐（PO4－P）排泄率按不同大小级别和培育时间进行了测定，同时估算了该浮游动物种群的PO4－P排泄率。结果表明，大型的特定PO4－P排泄率依其体重的增长呈指数式下降，并且随着培育时间的增加而大大降低。有鱼系统中大型种群的PO4－P排泄率及其与浮游植物PO4－P摄取率的比值都显著地小于无鱼系统，而放养罗非鱼或鳙的系统之二项估算值又明显地比鲢单养系统低。看来，大型种群的磷排泄在鲢单养系统的PO4－P再生中起有一定的作用，

江豚胎儿形态发生及生殖规律的研究

在胚胎发育早期，江豚上颌生有短须：左侧１－３根，右侧２－３根。具有半月形外耳廓。雄性胎儿阴茎露于体外。脐带较短。胎儿运动器官（胸鳍、尾鳍和尾柄）发育较快。随着胚胎的发育，外耳廓消失，阴茎藏于体腔。江豚胚胎发育过程中的这些形态学变化，再现了鲸类祖先在陆上生活的历史，同时也反映了鲸类在二次入水过程中所形成的对水环境的适应。此外。通过对收集的１７头江豚胎儿资料进行统计，结果表明长江江豚胎儿的生长速度约为９．０８ｃｍ／月（Ｏ．３０３ｃｍ／ｄ），妊娠期为９．４个月，交配季节为６－８月份，分娩为３－５月份。

鲮鱼和二代混精鲮鱼低温耐受能力的差异

采用LKB循环冷却装置以程序降温方式比较鲮鱼及二代混精鲮鱼(草鱼混精鲮或多精混精鲮再用草鱼精液进行混精受精所得子代)的耐寒性能。无论是在7.0℃条件下的耐受时间,还是对低温耐受的极限,二代混精鲮鱼均优于鲮鱼,但这种改善是有限的。作者认为,混精受精法不能从根本上解决鲮鱼的不耐寒性能。应该寻求其他更有效的育种途径。

黑龙江流域鲤鱼的繁殖、食性和生长

<正> 黑龙江流域各地区的渔获物中,鲤鱼所占的比例是相当大的。在黑龙江本流,每年夏季捕捞的主要对象是鲤鱼。在冬季生产中,鲤鱼的产量在整个鱼产量中亦占优势。著名的达赖湖的鱼产中,占主要成份的也是鲤鱼,冬季渔获物中鲤鱼约占70%左右,在夏季也占50%左右。鲤鱼在这一地区,除了天然捕捞生产的以外,也是一种主要的饲养鱼类。未来黑龙江水利枢纽建成后所出现的新水体中,鲤鱼可能是一种主要的养殖对象。因此,了解它的主要的生态问题和考虑它在水库中的发展方向以及应采取的措施都是必要的。

In vivo studies on the toxic effects of microcystins on mitochondrial electron transport chain and ion regulation in liver and heart of rabbit

This study examined the toxic effects of microcystins on mitochondria of liver and heart of rabbit in vivo. Rabbits were injected i.p. with extracted microcystins (mainly MC-RR and -LR) at two doses, 12.5 and 50 MCLReq. mu g/kg bw, and the changes in mitochondria of liver and heart were studied at 1, 3,12, 24 and 48 h after injection. MCs induced damage of mitochondrial morphology and lipid peroxidation in both liver and heart. MCs influenced respiratory activity through inhibiting NADH dehydrogenase and enhancing succinate dehydrogenase (SDH). MCs altered Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities of mitochondria and consequently disrupted ionic homeostasis, which might be partly responsible for the loss of mitochondrial membrane potential (MMP). MCs were highly toxic to mitochondria with more serious damage in liver than in heart. Damage of mitochondria showed reduction at 48 h in the low dose group, suggesting that the low dose of MCs might have stimulated a compensatory response in the rabbits. (C) 2008 Elsevier Inc. All rights reserved.

Generation and characterization of monoclonal antibodies against the flounder Paralichthys olivaceus rhabdovirus

Two MAbs (3C7 and 3C9) against flounder Paralichthys olivaceus rhabdovirus (PORV) were generated with hybridoma cell fusion technology and characterized by an indirect enzyme-linked immunosorbent assay, isotype test, Western blot and immunodot analysis and immunofluorescence assay. Isotyping tests demonstrated that both of the two MAbs belonged to IgM subclass. Western blot analysis showed the MAbs reacted with 42, 30, and 22 kDa viral proteins, which were localized within the cytoplasm of PORV-infected grass carp ovary (GCO) cells analyzed by indirect immunofluorescences tests. The MAb 3C7 was also selected at random for detecting virus antigens in the inoculated grass carp tissues by immunohistochemistry assay. Flow cytometry tests showed that at the 36 h postinfection (0.25 PFU/cell), the 23% PORV-infected GCO cells could be distinguished from the uninfected cells with the MAb 3C7. Such MAbs could be useful for diagnosis and potential treatment of viral infection. (C) 2007 Elsevier B.V. All rights reserved.

Sediment sources and the flood record from Wanghu lake, in the middle reaches of the Yangtze River

A sediment core was collected from the centre of Wanghu Lake, in the Middle Reaches of the Yangtze River. The recent part of the core was dated using a combination of Pb-210 and spheroidal carbonaceous particle (SCP) techniques. Extrapolating this chronology dated the laminated section of the core, between 723 and 881 mm, to the first half of the 18th century and this section was selected for detailed study. The thicknesses of the laminae were measured using reflecting and polarizing microscopes whilst geochemistry was determined by an electron probe. The thickness of the dark layers was found to be positively correlated with titanium concentrations, and negatively correlated with aluminium and potassium concentrations. The thickness of the light layers was found to be negatively correlated with the concentrations of titanium. It is concluded that the dark layers were deposited from the Fushui River, a tributary of the Yangtze River, under periods of normal flow whilst the light Layers were mainly deposited from the Yangtze River itself during flood periods. Documentary evidence for floods occurring in the take catchment corresponded with thick laminations of high titanium concentration. Further, two of the three thickest, light laminations with low titanium concentrations were found to be synchronous with recorded flood dates of the main Yangtze River in its Middle Reaches, but one was synchronous with a local drought. These data suggest that the Lake sediment provides an archive of the relative water levels of the Yangtze and Wanghu including floods of both the main Yangtze River and the local hydrological regime. (c) 2006 Elsevier B.V. All rights reserved.