独龙江中下游流域的鱼类区系

独龙江流域位于云南省的西北部,北与青藏高原相连,西与缅甸毗邻.中国科学院昆明动物研究所于2004年10月~11月对该水域鱼类资源进行了具体调查,共计采集到鱼类标本883号,分别属于鲤形目、鲇形目;裂腹鱼亚科、野鲮亚科、鮡科;共2目、3科(亚科)、6属、7种.对独龙江鱼类区系与其相邻水系的鱼类区系进行比较分析,认为独龙江水系的鱼类区系与怒江水系的鱼类区系有着更近的渊缘关系.

三峡水库香溪河库湾底泥中总氮、总磷含量的时空分布

2004年10月—2006年7月,对三峡水库香溪河库湾底泥中总氮(TN)、总磷(TP)含量的时空分布特征及其影响因素进行了分析.结果表明:香溪河库湾底泥中TN、TP含量均表现为"中间高,两头低"的空间分布规律,其中,TN含量最高值为1.08 mg.g-1,出现在库湾中部区域,最低值为0.89 mg.g-1,出现在河口附近区域;TP含量最高值为1.07 mg.g-1,最低值为0.80 mg.g-1,分别出现在库湾中部和库尾.TN含量按秋季、冬季、春季的顺序依次降低,从春季到夏季则大幅上升,夏季达最高值;TP

香港米浦基围塘中有机氯农药和多氯联苯在微型生物群落中的积累

分别在 2 0 0 1年和 2 0 0 2年用国家标准《水质 -微型生物群落监测 -PFU法》在香港米浦自然保护区的基围塘和红树林中监测水质 .在 3个基围塘中共鉴定出 91种原生动物 ,为香港地区的首次记录 .同时在群落级水平上分析了4种生态结构参数和 5种功能参数 .用化学的方法成功地监测出在此 3个基围塘的PFU挤出液中 pp′-DDE和PCB的浓度 ,并且获得两年一致性的结果 .本文化学和生物学结合的研究结果为测定水中超痕量持久性有机污染物 (POPs)的环境暴露与生态毒性提供了一种新的尝试 .图

利用微量热法研究Cd~(2+)和Cu~(2+)对嗜热四膜虫(Tetrahymena thermophila)的毒性效应

利用微量热法研究Cd2 + 和Cu2 + 对嗜热四膜虫BF5(TetrahymenathermophilaBF5)生长代谢毒性效应 ,结果表明 :①低浓度的Cd2 + (0～ 0 .4mgL-1)和Cu2 + (0～ 10mgL-1)对四膜虫的生长有促进作用 ,而高浓度的Cd2 + (0 .8～ 3.2mgL-1)和Cu2 + (2 0～ 2 0 0mgL-1)则产生抑制作用 ;②Cd2 + 和Cu2 + 的半抑制浓度IC50 分别为 2 .0 4mg/L和15 5 .5mg/L ;③联合毒性为协同作用

中国淡水产奥杜藻属的分类研究

对我国淡水产奥杜藻属植物的分类进行了研究总结,共有10种2变种,其中4个种为我国的新记录种,即赫曼奥杜藻Audouinellahermannii(Roth)Duby,大孢奥杜藻A.macrospora(Wood)SheathetBurkholder,优美奥杜藻A.eugenea(Skuja)Jao和矮小奥杜藻A.pygmaea(Kützing)Weber-VanBosse。

围隔中鲢和菹草控藻效果及其生态学意义

在滇池沿岸的池塘中 ,构建了面积为 10 0m2 ,水深为 85cm ,底质均为淤泥的四个围隔 ,其中在三个围隔内分别放养密度为 10 0g/m3 、75g/m3 、5 0g/m3 的鲢。它们均在一定程度上控制浮游植物的生物量并改善水体透明度 ,其中初始放养鲢 75g/m3 的围隔控制效果最明显。放养三种密度的鲢在有效控制微囊藻水华的同时 ,原先水体的优势种类发生质的变化 ,水体中浮游植物的多样性也明显增加。放鱼 2个月后 ,在生物操纵的围隔中同时种入菹草 ,在75g/m3 的鲢控藻的围隔中 ,菹草长势良

利用mtDNA 16S rRNA序列差异鉴定江西青岚湖的河蚌物种

对从青岚湖采集的 10属 14种河蚌的 19个样本进行了 16SrRNA的序列测定 ,并同GenBank中鄱阳湖流域相同物种河蚌的序列比较 ,分析了基于Kimura 2 parameter模型参数得到的遗传距离 ,并构建了它们的UPGMA树。结果显示 ,所有用于比较的河蚌种间遗传距离变化范围在 0 .0 2 74— 0 .2 2 90 ,平均为 0 .132 5 ,种内遗传距离在0 .0 0 34— 0 .0 0 6 8之间 ,平均为 0 .0 0 4 5 ,种间遗传距离远大于种内距离。表明以 16SrR

Characterization of development-related genes for the cestode Bothriocephalus acheilognathi

Differential gene expression of mature and immature Bothriocephalus acheilognathi cestodes was analyzed using the suppression subtractive hybridization technique. Five mature-associated cDNAs were isolated and characterized. Virtual Northern blot and RT-PCR analyses confirmed that four of the five genes were up-regulated in mature parasites. The sequence analysis revealed that one gene encoded the structural protein chorion precursor, and that three encoded functional proteins homologous to yolk ferritin, sodium/hydrogen exchanger and muscin-like protein. Another gene appeared to be specific to B. acheilognathi, encoding a putative metal-bound protein. Although results obtained in the present study are preliminary, the information about the five genes may provide clues for further investigation on the decline in parasite numbers during the maturation of B. acheilognathi.

Status of sturgeon aquaculture and sturgeon trade in China: a review based on two recent nationwide surveys

The authors reviewed the aquacultural history of Acipenseriformes in China, related the legal status and examined the current status of the cultured species or hybrids, origins of seedlings, quantities of production, geographic distribution in farming, and the sustainability for both restocking programmes and human consumption. The census shows that since 2000, the production of cultured sturgeons in China appears to have become the largest in the world. As of 2000, the rapid growth of sturgeon farming in China mainly for commercial purposes has shifted harvests in the Amur River from caviar production to the artificial culture of sturgeon seedlings. This dramatic development has also caused a series of extant and potential problems, including insufficient market availability and the impact of exotic sturgeons on indigenous sturgeon species. Annual preservation of sufficient higher-age sturgeons should be a national priority in order to establish a sustainable sturgeon-culture industry and to preserve a gene pool of critically endangered sturgeon species to prevent their extinction.

Qianlabeo striatus, a new genus and species of Labeoninae from Guizhou Province, China (Teleostei : Cyprinidae)

Qianlabeo striatus gen. et sp. nov. is described from a stream tributary to the Beipan Jiang of the upper Zhu Jiang (Pearl River) drainage in Matou, Anshun County, Guizhou Province, China. This monotypic genus is mainly characterized by its oromadibular morphology, namely an upper lip only present in and fully adnate to the side of the upper jaw, not covered by the pendulous rostral fold; the median portion of the upper jaw lacking an upper lip but bearing a thin, flexible and cornified cutting edge that is fully covered by the pendulous rostral fold; a postlabial groove prolonged, extended anteromedially close to the anteromost point of the midline of the lower lip but not to meet with its counterpart. The type species of this genus, Q. striatus has a longitudinal dark stripe along the side of the body.

Effect of replacement of dietary fish meal by meat and bone meal and poultry by-product meal on growth and feed utilization of gibel carp, Carassius auratus gibelio

Triplicate groups of gibel carp Carassius auratus gibelio (initial body weight: 5.25 +/- 0.02 g) were fed for 8 weeks at 20-25 degreesC on five isonitrogenous (crude protein: 400 g kg(-1)) and isoenergetic diets (gross energy: 17 kJ g(-1)). Meat and bone meal (MBM) or poultry by-product meal (PBM) were used to replace fish meal at different levels of protein. The control diet contained fish meal as the sole protein source. In the other four diets, 150 or 500 g kg(-1) of fish meal protein was substituted by MBM (MBM15, MBM50) or PBM (PBM15, PBM50). The results showed that feeding rate for the MBM50 group was significantly higher than for other groups except the PBM50 group (P < 0.05). Growth rate in the MBM15 group was significantly higher than that in the control (P < 0.05), while there was no significant difference in growth between the control and other groups (P > 0.05). Feed efficiency and protein efficiency ratio in MBM50 was significantly lower while that in MBM15 was significantly higher (P < 0.05). Replacement of fish meal by MBM at 500 g kg(-1) protein significantly decreased apparent dry matter digestibility (ADC(D)) and gross energy (ADC(E)) while apparent protein digestibility (ADC(P)) was significantly decreased by the replacement of MBM or PBM (P < 0.05). The results suggest that MBM and PBM could replace up to 500 g kg(-1) of fish meal protein in diets for gibel carp without negative effects on growth while 150 g kg(-1) replacement by MBM protein improved feed utilization.

Molecular cloning and characterisation of a fish PKR-like gene from cultured CAB cells induced by UV-inactivated virus

The double-stranded-RNA-dependent protein kinase (PKR) is an important component in an antiviral defence pathway that is mediated by interferon (IFN) in vertebrates. Previously, some important IFN system genes had been identified from an IFN-producing CAB (crucian carp Carassius auratus blastulae embryonic) cells after treatment with UV-inactivated GCHV (grass carp haemorrhage virus). Here, a fish PKR-like gene, named CaPKR-like, is cloned and sequenced from the same virally infected CAB cells. It has 2192 base pairs in length with a largest open reading frame (ORF) encoding a protein of 513 amino acid residues. BLAST search reveals that the putative CaPKR-like protein is most homologous to human PKR and also has a high-level homology with all members of a family of eIF2alpha kinases. Structurally, CaPKR-like possesses a conserved C-terminal catalytic domain of eIF2alpha kinase family and the most similarity to mammalian PKRs. Within its N-terminus, there are no dsRNA-binding domains conserved in mammalian PKRs instead of two putative Z-DNA binding domains (Zalpha). Like mammalian PKRs, CaPKR-like had a very low level of constitutive expression in normal CAB cells but was up-regulated in response to active GCHV, UV-inactivated GCHV and CAB IFN, implying that the transcriptional activation of CaPKR-like by viral infection is mediated possibly by newly produced CAB IFN, which was further supported by using cycloheximide, a potent inhibitor of protein synthesis. The results together suggested that CaPKR-like was the first identified fish gene most similar to mammalian PKRs. (C) 2004 Elsevier Ltd. All rights reserved.

Comparative study on the effect of dietary lipid level on growth and feed utilization for gibel carp (Carassius auratus gibelio) and Chinese longsnout catfish (Leiocassis longirostris Gunther)

An 8-week growth trial investigated the effect of dietary lipid level on growth performance of a carnivorous fish, Chinese longsnout catfish (Leiocassis longirostris Gunther) and an omnivorous fish, gibel carp (Carassius auratus gibelio). For each species, seven isonitrogenous semi-purified diets (455 g kg(-1) crude protein for Chinese longsnout catfish and 385 g kg(-1) crude protein for gibel carp) were formulated to contain 30, 60, 90, 120, 150, 180 or 210 g kg(-1) lipid. For Chinese longsnout catfish, feed intake (FI) decreased with increasing dietary lipid and there was no significant difference in feed intake from 90 to 210 g kg(-1) lipid. Specific growth rate (SGR) increased with dietary lipid level (P < 0.05) and the 150 and 180 g kg(-1) groups were the best. Feed conversion efficiency (FCE), protein retention efficiency (PRE) and energy retention efficiency (ERE) were higher at 180 g kg(-1) lipid. For gibel carp, FI decreased with increased dietary lipid and 180 and 210 g kg(-1) lipid groups showed lower values. SGR increased with dietary lipid level and the 150 and 180 g kg(-1) were the best. FCE was higher at 180 g kg(-1) lipid level. PRE increased with dietary lipid level and there was no significant difference in groups from 120 to 210 g kg(-1) dietary lipid. ERE increased with increasing dietary lipid level, and groups fed 120, 150 and 180 g kg(-1) lipid showed the highest values. In Chinese longsnout catfish, increase in dietary lipid level, resulted in increased carcass dry matter, crude protein, crude lipid and gross energy. In gibel carp, dry matter, crude protein, and crude lipid increased with dietary lipid level. Based on regression between SGR and dietary lipid, dietary lipid requirements for Chinese longsnout catfish and gibel carp were 142.6 and 140.5 g kg(-1), respectively.

无破坏性检测高电子迁移率晶体管外延材料性能的方法

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半导体激光器腔面钝化的方法

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