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排序方式: 共有249条查询结果,搜索用时 15 毫秒
41.
R. Bernaś A. Burzyński P. Dębowski A. Poćwierz‐Kotus R. Wenne 《Fisheries Management and Ecology》2014,21(5):398-409
Sea trout, Salmo trutta L., populations in the Slupia River basin have been affected by mass stocking with smolts and fry. This work is focused on a small‐scale differentiation in sea trout populations from one basin with a strong emphasis on the relationship between wild and hatchery origin fish. A total of 216 sea trout were genotyped at 10 microsatellite loci. Global FST obtained by amova was low at 0.0165. Pairwise FST were significant for all tests except wild and stocked adults. The highest pairwise difference was found between the hatchery sample and Kwacza (FST = 0.038). Analysis of the genetic structure revealed micro‐geographical differentiation with four subpopulations. The quality of the artificial spawning was found not to be adequate with a high risk of adverse effects to the whole population. All future stocking actions in the basin should consider the existing population structures. 相似文献
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Justyna Połedniok Joanna Orzeł Justyna Gałeczka Rozalia Czoik 《Communications in Soil Science and Plant Analysis》2017,48(8):936-942
A simple and very sensitive spectrophotometric method determining microgram quantities of gallium (Ga) has been developed. The method is based on the complex of Ga(III) with Chrome Azurol S (CAS) in the presence of benzyldodecyldimethylammonium bromide (ST) and polyoxyethylenesorbitan monopalmitate (Tween 40). The complex forms in weakly acid solution (pH 3.8) and shows the absorption maximum at 627 nm. The molar absorptivity (ε) of this system is 1.87 × 105 L mol?1 cm?1, and it is clearly higher than ε of other spectrophotometric methods of gallium determination. The detection and quantification limits (LOD, LOQ) are 7.6 × 10–3 and 0.023 µg mL?1, respectively. Beer‘s law is obeyed in the range from 0.02 to 0.60 µg mL?1 of Ga. The precision and accuracy are good. This first spectrophotometric method of Ga(III) determination in the four-component system has been successfully applied for the analysis of mushrooms and grasses with low content of gallium. 相似文献
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Philip Y. Lam Po Yee Chiu Hoi Yan Leung Na Chen Pou Kuan Leong Kam Ming Ko 《Fitoterapia》2010,81(8):1239-1245
The effect of schisandrin B (Sch B) on long-term ethanol-induced oxidative stress in various rat tissues was investigated. Long-term ethanol treatment increased reactive oxygen metabolites (ROM) level in plasma. The ethanol-induced oxidative stress was assessed by mitochondrial glutathione and α-tocopherol levels, antioxidant enzyme activities, malondialdehyde (mtMDA) production and heat shock protein (Hsp) 25/70 levels. Liver was most susceptible to oxidative stress with a significant increase in mtMDA production. Long-term Sch B treatment enhanced mitochondrial antioxidant status in a tissue non-specific manner. Sch B co-treatment ameliorated the alterations in plasma ROM levels, mtMDA production and Hsp 25/70 expression in rat tissues. 相似文献
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番木瓜环斑病毒(PRV)外壳蛋白(CP)基因cDNA克隆到pUC18上构型建成大肠杆菌(Escherichia coli)表达载体,Western blot检测结果表明该表达载体在E.clidDH5α中有两种特异蛋白表达,分子量为34kd的蛋白与推测的表达产物大小相符,且与PRVCP的一个“组分”大小相似;而分子量为16kd的蛋白可能是34kd蛋白的降解物或者是PRV CP基因不完全表达产物。 相似文献
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Ren‐Shih Chung Chong‐Ho Wang Chiun‐Wen Wang Yin‐Po Wang 《Journal of plant nutrition》2013,36(3):297-311
Effects of different nitrogen (N) sources on the growth and N accumulation of corn plants were studied on plots treated with a compost, a leguminous green manure, and a peat, respectively, associated with a chemical N fertilizer. The experiment included seven treatments with a no‐fertilization check and a conventional chemical fertilizer treatment. Whole corn plants were sampled, and total N was analyzed at 22, 33, 56, 77, and 120 days after seeding (DAS). The results showed that compost with an adequate amount of chemical N fertilizer could reach a high dry matter yield and a high N accumulation, even higher than those of the conventional chemical N fertilizer treatment. With green manure, a considerable amount of N was mineralized and utilized by the corn plants for growth and resulted in a good yield. Neither the peat nor the compost alone could supply enough N for the growth of corn plants. There were no significant effect of treatments on the distribution of dry matter yield and N accumulated in various organs. The crop growth rate of the corn plants of different treatments were significantly different at the vegetative growth stage, however, there were no significant difference during the grain filling period. The apparent N recovery of various treatments were between 0.22 to 0.51 kg N for each kg N applied. 相似文献
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In this study the effect of long‐term storage of liquid boar semen at different temperatures on motility, acrosome integrity and pH was investigated. Additionally, individual variation in sperm tolerance to storage at 10°C were examined. Beltsville Thawing Solution‐diluted AI doses from 16 randomly chosen Norwegian Landrace AI boars with proven fertility were split into subsamples and stored at 25, 20, 15 and 10°C, respectively. After 0, 24, 48, 72 and 96 h of storage, sperm motility, acrosome integrity and pH were determined. After 96 h, the initial percentage of motile sperm (77.8%) was significantly reduced to 52.2, 58.8, 50.9 and 42.8% by storage at 25, 20, 15 and 10°C, respectively. After an identical period of time, the percentage of acrosome intact sperm (95.8%) at time 0 became significantly reduced to 91.3, 91.3, 81.5 and 68.3% by storage at 25, 20, 15 and 10°C, respectively. The initial pH (7.21) decreased significantly to 6.96 and 7.06 after 96 h storage at 25 and 20°C, and increased not significantly to 7.25 for storage at 15°C and significantly to 7.29 at 10°C. In conclusion, the results from this study show that, according to the variables studied, 20°C is the least harmful of the four temperatures tested for the long‐term liquid storage of boar semen. Furthermore, remarkable differences in the individual resistance of boar semen to long‐term storage at 10°C were observed. 相似文献
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将携带有乙型肝炎病毒(adw亚型)表面抗原(HBsAg) 基因和HBsAg及其前导序列(HBsAg+preS1+preS2) 基因的植物表达载体pRoKII,分别导入农杆菌LBA4404中,通过叶盘转化法得到转基因番茄及其后代.Southern blot杂交证明两种外源基因已插入到植物染色体中.ELISA检测结果表明用HBsAg基因转化的番茄叶片和果实中都能表达HBsAg,而用含preS的HBsAg基因转化的番茄都测不出HBsAg的表达.通过免疫吸附电镜观察到有表达的叶片组织可提取出典型的Dane颗粒,其平均直径为22 nm. 相似文献