The Chinese sturgeon （Acipenser Sinensis） is one of the unique and important fishery resources in China. Since the construction of the Gezhouba Dam, the traditional migration route of the sturgeon has been blocked; ...The Chinese sturgeon （Acipenser Sinensis） is one of the unique and important fishery resources in China. Since the construction of the Gezhouba Dam, the traditional migration route of the sturgeon has been blocked; consequently, the length of natural spawning sites is reduced from 800 km in the past to less than 5 km at present. As an endangered species, the Chinese sturgeon has become one of the most conserved aquatic species. In this article, the flow field of its spawning states in the downstream of Gezhouba Dam was simulated and analyzed using N-S equations and k-ε turbulence model. Volume Of Fluid （VOF） method with the Finite Volume Method （FVM） was used to simulate the water-air two-phase flow to examine the computed area. On the basis of the ecological-hydraulic characteristics of Chinese sturgeon, the features of the flow field were investigated to provide theoretical support for the proper management of the Three Gorges Reservoir.展开更多
以自然患细菌性败血症的子二代中华鲟(Acipenser sinensis)幼鱼为研究对象,无菌操作从濒死病鲟体内分离到1株致病菌(zhx20120301)。结合传统细菌学鉴定及分子生物学鉴定方法,对其形态、生理生化特性、16S r DNA序列及系统发育分析等方...以自然患细菌性败血症的子二代中华鲟(Acipenser sinensis)幼鱼为研究对象,无菌操作从濒死病鲟体内分离到1株致病菌(zhx20120301)。结合传统细菌学鉴定及分子生物学鉴定方法,对其形态、生理生化特性、16S r DNA序列及系统发育分析等方面进行研究,研究结果显示这株细菌为维氏气单胞菌(Aeromomas veronii)。回归感染试验证实分离菌株具有较强的致病性,能导致健康杂交鲟(西伯利亚鲟Acipenser baerii♂×施氏鲟Acipenser schrenckii♀)死亡,并呈现与自然条件下相似的临床症状,且再分离菌株各种生理生化特性与原分离菌株相同。药敏试验结果表明该菌株对头孢氨苄、头孢唑啉、庆大霉素、四环素、强力霉素、氟苯尼考、多粘霉素B、恩诺沙星、氟哌酸和左氧氟沙星敏感。展开更多
Cystatin, a superfamily of cysteine proteinase inhibitors related to cathepsins and other cysteine proteinases, is widely distributed in animal tissues and body fluids. Although considerable attention has been given t...Cystatin, a superfamily of cysteine proteinase inhibitors related to cathepsins and other cysteine proteinases, is widely distributed in animal tissues and body fluids. Although considerable attention has been given to mammalian and avian cystatins, little data exist on cystatins from other vertebrates. In order to isolate fish cystatin cDNA, total RNAs were isolated from liver tissues of the Chinese sturgeon (Acipenser sinensis) and Amur sturgeon (Acipenser schrenckii), respectively. The cDNAs encoding the mature peptides of cystatin and the 3′ untranslated region of the two species of sturgeon were amplified by reverse transcription polymerase chain reaction (RT PCR) using total RNA as a template. The amplified cDNA fragments were inserted into pGEM T Easy vector and sequenced and the amino acid sequences deduced. Nucleotide sequence analysis showed that both cDNAs encode 112 amino acid residues of the mature cystatin peptide. The similarity of the two sturgeon nucleotide sequence coding regions and the deduced amino acid sequences were 99 4% and 100%, respectively. Analysis of the amino acid sequences indicate that the cloned cystatins were the homolog of the mammalian cystatin C. The amino acid residues of the functional regions are well conserved among different species, but there is considerable divergence in large portions of the coding region of two sturgeon cystatins in a variety of species.展开更多
基金Project supported by the Three Georges Construction Commission and the National Natural Science Foundation of China (Grant No. 30490231).
文摘The Chinese sturgeon （Acipenser Sinensis） is one of the unique and important fishery resources in China. Since the construction of the Gezhouba Dam, the traditional migration route of the sturgeon has been blocked; consequently, the length of natural spawning sites is reduced from 800 km in the past to less than 5 km at present. As an endangered species, the Chinese sturgeon has become one of the most conserved aquatic species. In this article, the flow field of its spawning states in the downstream of Gezhouba Dam was simulated and analyzed using N-S equations and k-ε turbulence model. Volume Of Fluid （VOF） method with the Finite Volume Method （FVM） was used to simulate the water-air two-phase flow to examine the computed area. On the basis of the ecological-hydraulic characteristics of Chinese sturgeon, the features of the flow field were investigated to provide theoretical support for the proper management of the Three Gorges Reservoir.
文摘Cystatin, a superfamily of cysteine proteinase inhibitors related to cathepsins and other cysteine proteinases, is widely distributed in animal tissues and body fluids. Although considerable attention has been given to mammalian and avian cystatins, little data exist on cystatins from other vertebrates. In order to isolate fish cystatin cDNA, total RNAs were isolated from liver tissues of the Chinese sturgeon (Acipenser sinensis) and Amur sturgeon (Acipenser schrenckii), respectively. The cDNAs encoding the mature peptides of cystatin and the 3′ untranslated region of the two species of sturgeon were amplified by reverse transcription polymerase chain reaction (RT PCR) using total RNA as a template. The amplified cDNA fragments were inserted into pGEM T Easy vector and sequenced and the amino acid sequences deduced. Nucleotide sequence analysis showed that both cDNAs encode 112 amino acid residues of the mature cystatin peptide. The similarity of the two sturgeon nucleotide sequence coding regions and the deduced amino acid sequences were 99 4% and 100%, respectively. Analysis of the amino acid sequences indicate that the cloned cystatins were the homolog of the mammalian cystatin C. The amino acid residues of the functional regions are well conserved among different species, but there is considerable divergence in large portions of the coding region of two sturgeon cystatins in a variety of species.
