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901.
斑节对虾杆状病毒(Penaeusmonodon-typebaculovirus,MBV)能危害斑节对虾(Penaeusmonodon)、万氏对虾(P.vannamei)、长毛对虾(P.penicilatus)、短沟对虾(P.semisulcatus)...  相似文献   
902.
斑节对虾“红体病”细菌性病原的初步研究   总被引:7,自引:0,他引:7  
从患“红体病”的斑节对虾中分离到8个菌株,通过致病力试验证实其中两个菌株是引起斑节对虾“红体病”的主要病原,使对虾死亡率分别达到70%和90%。根据生化试验,确定这两个菌株分别是嗜水气单胞菌和副溶血弧菌。抗药性实验的结果表明,嗜水气单胞菌菌株对强力霉素较为敏感,副溶血弧菌菌株对氟哌酸、红霉素、青霉素和强力霉素较为敏感。  相似文献   
903.
测定了碘伏消毒液对三种感染水生动物的病毒的杀灭作用和一些因素对碘伏消毒液消毒效果的影响。结果显示,含有效碘浓度为5mg/l的消毒液室温下处理5分钟,可灭活滴度为1075TCID50/ml的草鱼呼肠孤病毒和1070TCID50/ml的病毒性出血败血症病毒;含有效碘浓度为50mg/l的消毒液可灭活滴度为10575TCID50/ml的甲鱼虹彩病毒。细胞培养液中的有机成分对碘伏消毒液中有效碘浓度有较大的影响;酸碱度6~9之间,碘伏消毒液中有效碘浓度没有明显变化。  相似文献   
904.
Annual catch of the western sand lance Ammodytes japonicus in the eastern Seto Inland Sea, Japan, has shown a decreasing trend since the 1990s. To examine whether food shortage was the main cause for the catch decrease, we investigated the condition factor of the age‐0 fish at the beginning of the estivation period (late July) in Harima‐Nada, eastern Seto Inland Sea, for 10 years from 2008 to 2017. The mean abundance of copepods as food for the age‐0 fish during the fish growth period (from February to June) around the estivation area was also determined. The condition factor showed a significant decrease, and values for 2011 and later years were mostly lower than the known minimum threshold (4.2) for maturation. In the recent 4 years from 2013 to 2016, the mean copepod abundance was much lower than values for the other years. The condition factor showed a significant positive correlation with the copepod abundance. These results indicate that decline of western sand lance catch after 1990 was caused mainly by food shortage.  相似文献   
905.
The growth of Acropora in Sekisei Lagoon was investigated in situ using ceramic coral settlement devices (CSDs) and marine blocks (MBs) with small holes on their surfaces that were deployed prior to a mass spawning event. Acropora that had settled in 10-mm holes on the upper surface of the MBs were found to have grown inwards after 348 days post-mass spawning. After 733 days, the colonies had grown outwards, encrusting the blocks and attaining a maximum diameter of 21.5 mm (3.7 mm). CSDs that had been stacked above each other on frames were separated and observed in situ on 405 and 764 days after mass spawning. After 405 days, the maximum diameter of the encrusting Acropora was 7.6 mm (±2.4 mm), which increased to 19.4 mm (±5.5 mm) after 764 days, with 30% of colonies extending short branches. The length of the branches of Acropora grown on the CSDs fixed to the MBs 3 months after the mass spawning event exceeded the size of the encrusting portion of the colony 629 days after spawning. The mortality of colonies between 1 and 2 years was slight, with the temperatures conducive to coral bleaching that occurred during the study also having only a slight effect.  相似文献   
906.
纤维素酶的固体发酵生产及其应用研究   总被引:1,自引:0,他引:1  
纤维素酶是降解植物纤维素的一组酶,它能降解纤维素生成纤维二糖和葡萄糖等小分子物质.辽宁省酶工程技术中心通过研究进行小试、中试及建立纤维素酶生产线,找到了适宜的生产条件和工艺,并探索出一些应用领域的适宜条件.  相似文献   
907.
We have discovered multiple acidic cysteine protease inhibitors, in addition to the known Eel-CPI-1, in the skin mucus extract of the Japanese eel Anguilla japonica by using the two-dimensional gel system of gelatin reverse zymography. Two of the acidic inhibitors, which we have named Eel-CPI-2 and Eel-CPI-3, were purified to homogeneity by anion exchange chromatography on a column of DEAE-Sepharose CL-6B, followed by fast protein liquid chromatography on Superdex 75 10/300 GL and HiTrap Q HP columns. The amino acid compositions of Eel-CPI-2 and Eel-CPI-3 were found to be almost identical and closely similar to that of the eel galectin AJL1. The molecular masses of Eel-CPI-2 and Eel-CPI-3 were elucidated to be 16,089.080 and 16,089.137 Da, respectively, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The apparent dissociation constant of Eel-CPI-2 and Eel-CPI-3 for cysteine protease papain was determined to be 1.79 × 10−7 and 1.05 × 10−7 M, respectively, by a quartz crystal microbalance technique.  相似文献   
908.
Physiological methods, especially the use of isotopes of N, have allowed for the detailed characterizations of the several putative transport systems for nitrate and ammonium in roots of higher plants. In the last decade, the cloning of genes that appear to encode both high- and low-affinity transporters represent major advances, as well as substantiating the inferences based on earlier physiological methods. Nevertheless, the unexpected plethora of genes that have been identified now presents even greater challenges, to resolve their individual functions and to attempt to place these functions in a whole plant/environmental context.  相似文献   
909.
The activities of 44 Annonaceous acetogenins, which were originally isolated by monitoring plant fractionations with the brine shrimp lethality test (BST), were evaluated in the yellow fever mosquito larvae microtiter plate (YFM) assay. The results clearly demonstrate that most acetogenins have pesticidal properties. The structure–activity relationships indicate that the compounds bearing adjacent bis-THF (tetrahydrofuran) rings with three hydroxyl groups are the most potent. Bullatacin ( 1 ) and trilobin ( 7 ) gave the best activities against YFM with LC50 values of 0·10 and 0·67 mg litre-1, respectively. Compounds showing LC50 values below 1·0 mg litre-1 in this assay are usually considered significant as new lead candidates for pesticidal development. In the BST, the corresponding LC50 values were 1·6×10-3 ( 1 ) and 9·7×10-3 ( 7 ) mg litre-1. This is the first report of pesticidal structure–activity relationships for a series of Annonaceous acetogenins which are known to act, at least in part, as potent inhibitors of mitochondrial NADH: ubiquinone oxidoreductase. © of SCI.  相似文献   
910.
用玉米醇溶蛋白涂膜保鲜牛肉的研究   总被引:12,自引:3,他引:9  
采取不同灭菌方式对鲜牛肉进行表面灭菌,在不同组成的涂膜保鲜剂中浸渍一定时间,在0~4℃下贮存。结果表明:用有机酸混合液(2%醋酸+0.25%柠檬酸+0.1%抗坏血酸)对鲜牛肉进行表面灭菌后,在10%玉米醇溶蛋白+0.03%植酸+0.2%柠檬酸的80%乙醇溶液中浸渍1 min,0~4℃下贮存,保鲜期达35 d,各项指标仍符合国家鲜肉二级鲜度标准。  相似文献   
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