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51.
水稻白叶枯病菌对噻枯唑的抗药性监测   总被引:11,自引:0,他引:11  
采用活体寄主法和离体含药平板法 ,测定了 1999年安徽省滁州市田间水稻白叶枯病菌对噻枯唑的抗药性。结果表明 ,在水稻活体上存在噻枯唑抗药突变体 ,其比例为67.65%,比1997、1998年有较大程度升高 ,但是离体含药平板上未能监测到抗药突变体。  相似文献   
52.
综述了非放射性地高辛(DIG)标记系统的原理和主要特点,介绍了地高辛标记核酸探针的主要标记方法,影响探针标记方法选择的因素,标记探针的显色检测方法及其在食用菌研究领域的应用。  相似文献   
53.
AIM:To investigate the effect of the heat shock response on the reperfusion arrhythmias(RAs) and the possible mechanism involved. METHODS:Fifty-five Sprague Dawley rats were randomly divided into 2 groups: the heat shock group (group H,n=29) and the control group (group C,n=26). The rats in group H were preconditioned with heat shock 24 hours before, and that in group C were not. The hearts of 16 rats in group H and 16 in group C were exercised and mounted on a non-circulating Langendorff perfusion apparatus and perfused retrogradely with modified K-H buffer and mimic ischemia/reperfusion was applied. Additionally, conventional intracellular microelectrode techniques were used for recording such electrophysiological parameters as resting potential(RP), action potential amplitude(APA), over shot(OS), maximum depolarization velocity(Vmax) of the hearts of other 13 rats in group H and 10 in group C. RESULTS:①Prior heat stress significantly decreased reperfusion arrhythmia. ②The amount of CK release in the effluent in group H was much less than that in group C. ③Myocardial HSP70 content was elevated significantly in group H. ④Heat stress significantly increased myocardial anti-oxydases activity and decreased lipid peroxydative products. Additionally, heat stress significantly reduced the Vmax of action potential. It indicated that rapid Na+ channel of papillary muscles may be inhibited by heat shock. The degree of change of Vmax after ischemia in H group was significantly less than that in group C. And the time of reperfusoin with Tyrode's solution till the action potential appeared as large as that before perfusion with mimic ischemic solution is shorter in group H than in group C. CONCLUSION:Heat shock pretreatment markedly reduces ischemia/reperfusion-induced injury of heart and ventricular arrhythmias in rats and this effect may be associated with the inhibition of rapid Na+ channel of papillary muscles by heat shock and the increase in myocardial HSP70 and anti-oxydase activity.  相似文献   
54.
AIM:To examine the effects of recombinant human hepatocyte growth factor(rhHGF) and native calf HGF(cHGF) on SMMC-7721 human hepatocellular carcinoma(HCC) cell line. METHODS:Human HCC cell line culture, photometric assay, and flow cytometric assay were used in this study .RESULTS:A similar type of dose-dependent cell growth inhibition effect on SMMC-7721 human HCC cells by rhHGF(5-20 μg/L) as well as by cHGF(25-100 mg/L) had been found, with the maximal effect at the highest concentration used. Approximately over 50% of the cells treated with rhHGF(5 μg/L, 10 μg/L, 20 μg/L) accumulated in the quiescent G0/G1 phase of the cell cycle over incubation periods for 3 d. CONCLUSION:The growth of SMMC-7721 human HCC cells was strongly inhibited by both rhHGF and cHGF. This might be because the cells exposed to HGF became arrested in the G0/G1 phase.  相似文献   
55.
AIM: To examine the effect of traditional chinese medicine recipe, Taoren Honghua(semen persicae-flos carthami) decoction, on hyperlipidemia without symptom. METHODS: The plasma TC, TG, LDL, HDL, apolipoprotein(Apo) A, Apo Bof the patients with hyperlipidemia without symptom were measured using automatic analyzer (shimadiu CL-7200), the production of nitric oxide(NO) was detected by Greiss reaction, and SODactivity and MDAformation were examined using o-trihydroxy benzene and barbituric methotheds, respectively. RESULTS: After oral administration of Taoren Honghua decoction, the plasma levels of TC, TG, LDL, and MDAof the patients were markedly decreased, however, the plasma levels of ApoA, HDL, SODand NOwere significantly increased and almost no change was detected in the plasma level of Apo B. In control group, it was found that although the plasma level of TC, TG and LDL were decreased ( P<0.05 ) and ApoAas well as HDLwere increased, ApoB, SOD, MDA and NO production were all unchanged. CONCLUSION: The traditional chinese medicine recipe, Taoren Honghua decoction,has a significant therapeutic effect on patients with hyperlipidemia by removing blood stasis, promoting qi circulation and in turn reducing blood lipid level.  相似文献   
56.
棉疫病菌elicitin基因的克隆与序列分析   总被引:1,自引:0,他引:1  
 棉疫病菌是我国棉花和苎麻疫病的主要病原菌,引起棉花烂铃、死苗,苎麻叶斑和茎腐,严重影响棉花和苎麻的产量和品质[1,2],该菌的主要寄主有棉花、苎麻和构树[3]。  相似文献   
57.
用禽多杀性巴氏杆菌强毒株(C48-1)与弱毒株(G190E40和B26-T1200)制备的蜂胶灭活疫苗的免疫原性对比试验结果表明,强毒株C48-1制备的禽霍乱蜂胶灭活疫苗的免疫效果显著高于弱毒株G190E40和B26-T1200,近期保护率相差20%~40%,3个月后相差40%~80%.强毒株C48-1的免疫原性显著高于弱毒株G190E40和B26-T1200,说明禽多杀性巴氏杆菌荚膜上的毒力蛋白可能具有免疫原性.  相似文献   
58.
为寻找其他有效的禽霍乱蜂胶灭活疫苗的效检方法,应用小白鼠代替本动物鸡对禽霍乱蜂胶灭活疫苗进行效检.结果表明,小白鼠免疫时体重15~18 g,疫苗免疫剂量0.3 mL/只,免疫10 d后攻毒,攻毒时体重20~25 g,攻毒剂量5~9 CFU/只时,可代替本动物鸡对禽霍乱蜂胶灭活疫苗进行效检,判定标准为免疫组8/10以上保护,对照组5/5死亡为合格.本效检方法可缩短检验期限7 d,降低检验成本,具有敏感、特异、客观、简便等特点.  相似文献   
59.
从姬松茸子实体的热水提取物中分离纯化出组分ABP-Ⅱ-a。高压液相层析测得其相对分子量为52500,红外扫描显示有典型的多糖吸收峰。气相色谱分析表明,其单糖组成为葡萄糖、甘露糖、半乳糖和少量阿拉伯糖,摩尔比为35.24:5.19:1.91:1。  相似文献   
60.
稻曲病侵染时期和流行因素研究   总被引:3,自引:0,他引:3  
分期接种试验的结果表明,稻曲病对水稻的侵染时期,主要在孕穗末期至破口期,病菌侵入籽粒在水稻开花前。3a的系统调查和对比分析结果说明,水稻穗期最高气温>32℃的天数少,降雨量大,有利病菌的侵入和发展流行,品种间抗(耐)病性差异显著。近年来稻曲病发生严重的主要原因是单季晚稻的大面积种植,穗期气候条件适宜病害发生流行。  相似文献   
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