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81.
本文就类鼻疽(melioidosis)的流行病学,诊断方法,免疫机理,发病机理及治疗方法 进行了综述。为重视该病的研究提出了建议。  相似文献   
82.
三倍体葡萄新品种‘红标无核''   总被引:5,自引:0,他引:5  
‘红标无核'是以二倍体‘郑州早红'×四倍体‘巨峰'育成的三倍体无核葡萄品种.果实极早熟,比‘巨峰'早熟30 d,果粒大,紫黑色,无核,果肉较脆,品质上等,可溶性固形物含量15.4%,结实力强,丰产,抗病,适应范围广,适宜鲜食和加工罐头.  相似文献   
83.
AIM:To investigate the expression of soluble guanylate cyclase protein and its mRNA in rat pulmonary artery after exposure to hypoxia and hypercapnia.METHODS:Male Sprague-Dawley rats were randomly split into 4 group, which were hypoxic hypercapnic (HH 1 week, HH 2 weeks, HH 4 weeks) group and control group, to copy pulmonary hypertensive animal model. The expression of sGCα1 and β1 subunits protein of medial and small pulmonary artery was performed by immunohistochemistry with a polycolonal antibody. In situ hybridization was performed on the rat lung tissue using sGC oligonuclear probe to assay the expression of sGCα1subunit mRNA.RESULTS:The sGCα1 and β1 subunits protein and sGCα1 subunit mRNA were faint staining in the pulmonary small and medium artery in HH1 week, HH 2 weeks and HH 4 weeks groups compared with control group (all P<0.01).CONCLUSION:sGC subunit mRNA and protein expression in pulmonary small and medium artery were decreased after exposure to hypoxia and hypercapnia, which took part in the development of the pulmonary hypertension.  相似文献   
84.
以稗草为生物测定材料,运用二次正交旋转组合设计,以土壤湿度和除草剂用量二因子为决策变量,对稗草的抑制率为目标函数,研究土壤湿度对三氮苯类除草剂药效的影响。结果表明,适当的土壤水分是三氮苯类除草剂发挥药效的重要因素,药效随土壤湿度的提高而提高。不同的土壤湿度对不同除草剂药效影响各异,高湿条件下,湿度差异对药效影响大小依次为嗪草酮、西草净、扑草净、莠去津,低湿条件下则相反。除草剂用量与土壤湿度存在最佳发挥药效的组合。  相似文献   
85.
氟虫腈(锐劲特)对水稻害虫防治效果及增产效应   总被引:6,自引:0,他引:6  
为了阐明新一代杀虫剂氟虫腈(锐劲特)对二化螟、三化螟、稻纵卷叶螟的防治效果及应用前景,进行了水稻盆栽试验、田间防效试验,并对施用锐劲特后水稻叶绿素含量、功能叶叶面积和产量进行了测定。结果表明,锐劲特施药后13天接虫的三化螟幼虫死亡率仍高达94.44%。在田间防效试验中,每公顷施用锐劲特80%WG有效成分24g防治二化螟,防止枯心效果达97.62%,防止白穗效果达94.44%,害虫死亡率达96.15%;每公顷施用锐劲特5%SC有效成分22.5g防治晚稻三化螟,保苗效果可达95.91%,害虫死亡率达99.04%;每公顷施用锐劲特5%SC有效成分30g防治稻纵卷叶螟,保叶效果达97.88%。叶绿素含量比对照增加32.4%;每公顷施用锐劲特80%WG有效成分36g时,功能叶叶面积增加16%~27.5%,并且杂交稻博优湛19比常规稻早糯3321和早熟早籼815对锐劲特更敏感。每公顷施用锐劲特5%SC有效成分22.5~37.5g时,水稻株高增加4.0~6.1cm,每稻丛穗数增加2.6%~31.18%,结实率提高19.43%~33.97%,水稻产量增加21.58%~28.19%。  相似文献   
86.
番木瓜环斑病毒株系的分子生物学方法鉴定   总被引:6,自引:1,他引:6  
 以PRSV株系特异性引物对PRSV的PRSV126(PRSV日本分离物)、Ys、Vb和Sm等株系进行RT-PCR方法鉴定,引物PR21/PR22能把Ys从Vb和Sm中鉴定出来,PR300/PR301则能把Vb从Ys、Sm和PRSV126中鉴定出来;用限制性内切酶Hae Ⅱ、Sau3A I和Hinf I对PRSV的PRSV126、Ys、Vb和Sm等株系进行单酶切RT-PCR-RFLP分析,Hinf I能把PRSV126与Ys、Vb和Sm鉴别开来,Sau3A I能把Ys与Vb和Sm鉴别开来,Hae Ⅱ则能把Ys与PRSV126、Vb和Sm鉴别开来;以P1/P2为引物,对Vb、Ys和Sm株系进行RT-PCR-RFLP-SSCP分析,结果能一次把三者较好地区别开来。  相似文献   
87.
 以稀释倒平板法从0型菌086和IV型菌967-4和9620中分离到59个单细胞系;在12个近等基因系品种上,086和其单细胞系表现为弱毒力,2个IV型菌及其单细胞系能克服抗病基因Xa-1、2、3、8、10、11、14的抗性,不能克服Xa-21、4、5、7、13的抗性;带主效抗病基因的品种Asominori、XM5、M41、XM6和丰锦能把3个母株的59个单细胞系区分为12种数量差异或质量差异的不同致病型;将此5品种与近等基因系配合,适合作为病菌致病基因变异频度监测的寄主;采用"段叶沙培,切口取菌胶"法分离病菌,在中国致病型鉴定品种上划分的致病型,是田间病菌群体毒力结构的表型反应。  相似文献   
88.
葡萄属植物白藜芦醇研究进展   总被引:35,自引:1,他引:35  
根据有关文献分别从白藜芦醇穴Res雪的发现、化学结构、物理特性、对葡萄属植物及人体健康的作用、作用机理方面作了简要概述,总结了其诱导、取样、测定方法,在葡萄植物体内的分布、动态变化、器官之间含量的相关性,葡萄属植物种间、品种间及葡萄加工品之间的含量差异,并介绍了白藜芦醇的生物合成、几种合成酶,影响代谢的内部、外部因素,对白藜芦醇的研究意义及应用前景也进行了讨论。  相似文献   
89.
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   
90.
AIM: To investigate the effects of PD98059 on the differentiation from mesenchymal stem cells to osteoblasts.METHODS: hMSC were separated from human marrow and expanded in cuture medium. hMSC were induced with dexamethasone, β-glycerophosphate, vitamin C which acted as osteoblast differentiation inducer. PD98059 was added into the osteoblasts induction medium. The cells were assayed with cell morphology, alkaline phosphatase (AP) activity and calcium deposition. RESULTS: The isolated cultured MSC comprised a single phenotypic population and displayed a fibroblast-like morphology. After induced with osteoblasts induction medium, the cells showed changes in cell morphology from spindle-shape to cuboidal and polygonal. The AP activity increased gradually and reached the peak in 12 days, then decreased. Many scattered tangerice calcium nodes were observed. PD 98059 significantly inhibited AP activity and calcium deposition in a dose-dependent manner. A striking observation of the present study was that a few adipocytes appeared in cultures that were treated with PD 98059 and osteogenic differentiation medium. CONCLUSION: These results indicated that osteogenic diferentiation from the hMSCs was related to the activation of the ERK.  相似文献   
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