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甜菜总DNA不同提取方法的研究 总被引:2,自引:0,他引:2
采用CTAB法、SDS法、改进CTAB法和改进SDS法提取甜菜总DNA,并对提取得到的DNA进行质量鉴定和PCR扩增效果检测.结果表明:用改进的CTAB法提取的甜菜总DNA OD260/OD280在1.8左右,DNA纯度好,产率高,CTAB法和改进的SDS法产率次之,SDS法最低.同时对改进的CTAB法的提取条件进行优化,即用5.0 mL细胞提取液,0.8 mL无水乙醇, 0.6倍体积的异丙醇,可从1.0 g甜菜叶片中提取到高质量高纯度的DNA 764 μg/g. 相似文献
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M.J. SÁNCHEZ-MUROS L. GARCÍA-REJÓN J.A. LUPIÁÑEZ M. DE LA HIGUERA 《Aquaculture Nutrition》1995,1(4):213-220
The adaptive response of the kinetics of glucose 6-phosphate dehydrogenase (G6PDH) was studied in trout liver and kidney after feeding (control or high-protein/non-carbohydrate diet) or starving for 30 days, as well as influences on growth and other nutritive parameters. Typical Michaelis-Menten kinetics were found for the hepatic catalysis of G6PDH under all conditions studied, without evidence of sigmoidicity. The administration of a high-protein/non-carbohydrate diet (61.0% protein, 7.9% lipids) produced no significant changes in specific activity or other kinetic parameters of the liver enzyme. This nutritional situation caused a significant daily increase in relative growth (20%) and feed efficiency (13.5%), as well as a 13% decrease in the protein-conversion efficiency, with respect to the control diet (46% protein, 8% lipids, 22% carbohydrates). On the other hand, long-term starvation (30 days), as a lipolytic condition, significantly decreased the activity and catalytic efficiency of hepatic G6PDH, by almost 45%, without significant changes in the Km and activity-ratio values. These changes agree with a fall in the intracellular concentration of the enzyme as a consequence of a protein-repression process. The activity of the renal G6PDH was less than in the liver of control fish, and no variation in kinetics was found under the high-protein diet or starvation. This behaviour clearly demonstrates that the kidney pentose-phosphate pathway showed no adaptive response in relation to synthesis of fatty acids and other lipids. 相似文献
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Tengelsen LA Bowen RA Royals MA Campbell GL Komar N Craven RB 《Journal of the American Veterinary Medical Association》2001,218(9):1469-1473
OBJECTIVE: To evaluate humoral immune responses of emus vaccinated with commercially available equine polyvalent or experimental monovalent eastern equine encephalomyelitis (EEE) virus and western equine encephalomyelitis (WEE) virus vaccines and to determine whether vaccinated emus were protected against challenge with EEE virus. DESIGN: Cohort study. ANIMALS: 25 emus. PROCEDURE: Birds were randomly assigned to groups (n = 5/group) and vaccinated with 1 of 2 commercially available polyvalent equine vaccines, a monovalent EEE virus vaccine, or a monovalent WEE virus vaccine or were not vaccinated. Neutralizing antibody responses against EEE and WEE viruses were examined at regular intervals for up to 9 months. All emus vaccinated with the equine vaccines and 2 unvaccinated control birds were challenged with EEE virus. An additional unvaccinated bird was housed with the control birds to assess the possibility of contact transmission. RESULTS: All 4 vaccines induced detectable neutralizing antibody titers, and all birds vaccinated with the equine vaccines were fully protected against an otherwise lethal dose of EEE virus. Unvaccinated challenged birds developed viremia (> 10(9) plaque-forming units/ml of blood) and shed virus in feces, oral secretions, and regurgitated material. The unvaccinated pen-mate became infected in the absence of mosquito vectors, presumably as a result of direct virus transmission between birds. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that emus infected with EEE virus develop a high-titer viremia and suggest that they may serve as important virus reservoirs. Infected emus shed EEE virus in secretions and excretions, making them a direct hazard to pen-mates and attending humans. Commercially available polyvalent equine vaccines protect emus against EEE virus infection. 相似文献
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本试验旨在探究不同蛋白质水平补饲料对3月龄早期断奶犊牦牛生产性能、血液指标和胃肠道发育的影响。选取3月龄(90±5)日龄]健康大通母犊牦牛48头,随机分为4组,每组4个重复,每个重复3头。对照组犊牛全放牧,试验组犊牛在放牧基础上分别补饲不同蛋白质水平(粗蛋白质水平分别17%、18%、19%)的3种等能量(增重净能5.6 MJ/kg)饲粮。预试期7 d,正试期60 d。结果表明:1)与对照组相比,补饲能够显著提高犊牦牛的平均日增重,17%、18%和19%补饲组分别提高了28.87%、47.47%和28.61%(P0.05)。2)与对照组相比,补饲显著提高了血清尿素氮浓度(P0.05),17%、18%和19%补饲组分别增加了10.57%、16.64%、21.84%(P0.05)。3)与对照组组相比,补饲料粗蛋白质水平为18%时,显著提高了瘤胃和大肠的绝对重量和相对重量(P0.05),显著提高了十二指肠、盲肠、结肠的绒毛高度以及十二指肠和盲肠的绒毛高度/隐窝深度(P0.05)。因此,补饲能够提高早期断奶母犊牦牛生产性能和促进胃肠道发育,早期断奶母犊牦牛的补饲料的适宜粗蛋白质水为18%。 相似文献