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1.
黄瓜根腐病致病病原的鉴定   总被引:6,自引:0,他引:6  
在天津市及周边地区采集病株进行组织分离,同时分离到两类病原菌,经初步的生物学特性鉴定表明,引起黄瓜根腐病的主要病原菌为甜瓜疫霉、尖孢镰刀菌和茄病镰刀菌。经接种试验,认为甜瓜疫霉为主要致病菌。  相似文献   
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采用Sevag法、三氯乙酸(TCA)法和Sevag法与三氯乙酸法相结合的方法对褐藻糖胶进行脱蛋白研究,并研究脱蛋白与未脱蛋白对褐藻糖胶脱色的影响.结果表明,Sevag法与三氯乙酸法相结合脱蛋白效果最佳,当Sevag法操作2次,TCA溶液添加量为1.3 mL/10mL多糖溶液时,蛋白脱除率为78.68%,多糖损失率为28...  相似文献   
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中越水稻迁飞性害虫稻飞虱、稻纵卷叶螟发生关系分析   总被引:3,自引:0,他引:3  
中越两国同属东亚季风区,水稻病虫害在发生危害上为一个整体。每年水稻稻飞虱、稻纵卷叶螟(以下简称"两迁"害虫)随着季节和气温变化,在两国间往返迁飞,发生为害,相互影响。研究两国水稻迁飞性害虫发生的关系和影响规律,对于提高监测预警的早期预见性和防控工作的主动性,有效控制其危害具有重要意义。2010年以来,中越两国实施了中越水稻迁飞性害虫监测与防治合作项目,通过连续多年开展交流合作,初步明确了越南"两迁"害虫发生规律。本文简要分析了影响越南"两迁"害虫发生的主要因素,探讨了中越两国水稻"两迁"害虫发生规律的相关性,对提高中国"两迁"害虫中、长期预报能力和综合治理水平发挥了积极作用。  相似文献   
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选用PK-15传代细胞系从吉林农业大学鹿场采集的梅花鹿粪样病料中分离出一株病毒,经血凝试验、血凝抑制试验及电镜观察对该病毒进行鉴定。结果表明:该病毒为鹿源细小病毒。  相似文献   
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Among many detrimental injuries, alcohol is implicated in hepatitis, fatty liver, hepatic fibrosis, and cirrhosis. The purpose of this study was to evaluate the protective effect of bio-active ceramic water on alcohol-induced hepatic injury in pigs. Twelve male Landrace pigs were divided into 3 groups. Groups 1, 2, and 3 were fed with bio-active ceramic water + normal liquid diet, bio-active ceramic water + liquid diet containing 15% ethanol, and tap water + liquid diet containing 15% ethanol for 12 weeks, respectively. For serological, histopathological, and immunohistochemical analysis, all pigs were sacrificed at week 12. In group 3, serum ALT and AST levels increased, and mild fatty change and moderate necrosis were detected in the liver. Collagen fibers, myofibroblasts, and CYP2E1 were also increased or activated in group 3. In group 2, there were mild hepatic injuries compared to group 3. However, injuries and activations were not observed in the liver in group 1. We suggest that the bio-active ceramic water used in the present study had protective capability against ethanol-induced hepatic injury and that having no toxic effect on the pig liver. The bio-active ceramic water might be useful as a therapeutic drinking water in patients suffering from alcoholic liver diseases.  相似文献   
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The link between dietary fats and cardiovascular diseases has necessitateda growing research interest in palm oil, the second largest consumedvegetable oil in the world. Palm oil, obtained from a tropical plant, Elaeis guineensis contains 50% saturated fatty acids, yet it does notpromote atherosclerosis and arterial thrombosis. The saturated fatty acidto unsaturated fatty acid ratio of palm oil is close to unity and it containsa high amount of the antioxidants, -carotene, and vitamin E. Although palm oil-based diets induce a higher blood cholesterol level thando corn, soybean, safflower seed, and sunflower oils, the consumption ofpalm oil causes the endogenous cholesterol level to drop. Thisphenomenon seems to arise from the presence of the tocotrienols and thepeculiar isomeric position of its fatty acids.The benefits of palm oil to health include reduction in risk of arterialthrombosis and atherosclerosis, inhibition of endogenous cholesterolbiosynthesis, platelet aggregation, and reduction in blood pressure. Palm oilhas been used in the fresh state and/or at various levels of oxidation.Oxidation is a result of processing the oil for various culinary purposes.However, a considerable amount of the commonly used palm oil is in theoxidized state, which poses potential dangers to the biochemical andphysiological functions of the body. Unlike fresh palm oil, oxidized palm oilinduces an adverse lipid profile, reproductive toxicity and toxicity of thekidney, lung, liver, and heart. This may be as a result of the generation oftoxicants brought on by oxidation. In contrast to oxidized palm oil, red orrefined palm oil at moderate levels in the diet of experimental animalspromotes efficient utilization of nutrients, favorable body weight gains,induction of hepatic drug metabolizing enzymes, adequatehemoglobinization of red cells and improvement of immune function. However, high palm oil levels in the diet induce toxicity to the liver asshown by loss of cellular radial architecture and cell size reductions whichare corroborated by alanine transaminase to aspartate transaminase ratioswhich are higher than unity.The consumption of moderate amounts of palm oil and reduction in thelevel of oxidation may reduce the health risk believed to be associated withthe consumption of palm oil. Red palm oil, by virtue of its-carotene content, may protect against vitamin A deficiency andcertain forms of cancer.  相似文献   
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Spontaneously hypertensive rats (SHRs) are widely accepted in medical research because this model has been used for studies in neurodegenerative diseases such as vascular dementia and stroke. In the present study, we observed newly generated neuronal precursors using doublecortin (DCX, a marker of neural proliferation and differentiation) in the subgranular zone of the dentate gyrus in SHRs compared to Sprague-Dawley rats (SDRs) at various age stages. DCX immunoreactivity, immunoreactive cell numbers and its protein level in the dentate gyrus of the SHRs were higher than those in the SDRs at postnatal month 1 (PM 1). At PM 8, DCX immunoreactivity, immunoreactive cell numbers and protein levels in both groups were markedly decreased compared to those at PM 1; however, they were higher than those in the SDRs. They were decreased in the both groups with age: DCX immunoreactive cells in the SDRs were few at PM 12. Our results indicate that newly generated neuronal precursors are more abundant in SHRs than in SDRs during their life.  相似文献   
10.
Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.  相似文献   
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