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31.
AIM:To investigate the effects of fibronectin (FN) on the proliferation and collagen synthesis in cultured rat cardiac fibroblasts (CFb) derived from SHR (CFbSHR) and WKY (CFbWKY). METHODS:CFb derived from 12-week-old spontaneously hypertensive rat (SHR) and WKY was cultured by outgrowth of tissue block. Cell proliferation of CFb was measured by cell number counting and[3H]-TdR incorporation using 24-well plates pre-coated with 5 μg/cm2 of FN. Collagen synthesis was determined by [3H]-proline incorporation. RESULTS:As compared with control, the cell number of fibroblasts derived from SHR and WKY were significantly increased to 163.75% and 170.42% respectively after 72 h incubation with FN in the presence of 0.4% FCS from a intial cell density of 1×104 cells/mL. DNA synthesis of CFb was markedly promoted by FN. FN induced an increased in [3H]-proline incorporation in both CFbSHR and CFbWKY. CONCLUSION:FN is able to promote cell proliferation and collagen synthesis of CFb derived both from SHR and WKY. 相似文献
32.
孔雀河流域绿洲生态支持系统调控模式研究 总被引:8,自引:0,他引:8
生态环境用水量的减少是孔雀河流域近 50年来现代绿洲环境退化的主要原因 ,维持生态与社会经济的合理用水比例是绿洲系统持续发展的前提。以此为基础 ,本文采用水资源承载力的方法探讨了绿洲生态支持子系统和社会经济子系统优化调控模式 ,最后就配置方案及发展模式的可行性进行了分析 相似文献
33.
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
34.
35.
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
36.
CHEN Xiao-yin ZHANG Qun YANG Qin-he XIE Qiu-ling SHEN Qiang XU Yun-sheng 《园艺学报》2002,18(12):1529-1531
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
37.
淡紫拟青霉菌料防治大豆胞囊线虫的后效研究 总被引:6,自引:2,他引:6
淡紫拟青霉不同菌株的培养菌料,施225kg/hm2,对大豆胞囊线虫不但当年有45%~69%的较好防效,而且第2年和第3年仍然有22.5%~37.7%和7.3%~22.9%的后效,即空胞囊和被寄生的胞囊数量增加。 相似文献
38.
玉米螟赤眼蜂适宜生境的研究和利用:I.玉米螟赤眼蜂在不同生境中的分布与种群消长 总被引:3,自引:0,他引:3
本文通过对华北地区有代表性的作物生境,采用人工挂卵的方法,系统调查研究了玉米螟赤眼蜂在17种生境中的分布和种群动态。结果表明,玉米螟赤眼蜂在不同生境中的分布、发生时间和种群数量有所不同,说明其对生境有一定的选择性。玉米螟赤眼蜂自然种群消长有4个峰,其中以春甘薯田的发生时间最长,种群数量最大,最具代表性。这4个峰在春高粱间作菜豆、春花生、平作夏玉米和夏玉米间作直立型绿豆这4种生境中也不同程度地出现。间作豆科作物可在一定程度上提高玉米螟赤眼蜂的寄生率。玉米螟赤眼蜂种群数量年度间变异较大,特别是干旱的影响最为明显。 相似文献
39.
苏云金杆菌GC—91发酵上清液的增效作用 总被引:10,自引:0,他引:10
利用生物测定,SDS-PAGE方法对苏云金杆菌GC-91发酵液的上清液进行了研究。研究表明,上清液中含有增效物质,离心丢弃上清液是导致毒力收率大幅度下降的根本原因。上清液对粉剂增效明显,本实验中最高增效倍数为23.5倍,且上清液对不同菌种粉剂增效力不同,对GC-91菌粉增效极为显著,对HD-1菌粉增效较为缓慢。上清液中含有的增效物质是一种热稳定物质,能耐15分钟沸水浴,在pH2~10范围内稳定,证明不是β-毒素 相似文献
40.