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AIM: To demonstrate the susceptibility of cell apoptosis varies during the progress of cell malignant transformation from human being in vitro. METHODS: A SV40T-transfected human bronchial epithelial immortalized cell line (called M) was selected in this work, which has acquired some characteristics of malignant transformation at the later passage. The alterations of apoptosis and bcl-2, P53 genes between early and later passage of M cells were investigated by means of TDT labeling in situ, chromosome FISH, RNA and protein testing, etc. RESULTS: Incidence of apoptosis induced by cis-platin was significantly lower in later than in early passages of M. Levels of bcl-2 mRNA and protein in later passages were higher than early passages of M, and overexpression of bcl-2 was accumulated following the development of cellular malignancy. P53 protein level was as high in early as in later passages. CONCLUSION: Overexpression of bcl-2 decreases the cellular sensitivity to apoptotic inductors plays an important role during progress of carcinogenesis in human bronchial epithelial cancers. The inactivation of P53 protein in the SV40-T transfected M cell line may be one of reasons of bcl-2 overexpression, but not associated with the accumulation of bcl-2 expressed level during cell transformation. 相似文献
93.
Polysulfonamide (PSA) has been widely used in many fields because of its excellent thermodynamic properties. In this study, PSA fibers were prepared separately via two different spinning ways, including conventional wet spinning and electrospinning. Fluid motion of wet spinning and electrostatic field of electrospinning were modeled using finite element analysis to investigate the spinning process. The properties of fabricated PSA fibers were characterized systematically by scanning electron microscope (SEM), fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), thermal gravity analysis (TGA) and electronic strength tester. Based on the simulation and theoretical analysis of spinning process, it was found that the extruding force of the wet spinning is larger than that of the electrospinning. The larger extruding force makes the alignment of macromolecules inside fiber relatively uniform, and a higher proportion of crystallization happens. Accordingly, the mechanical properties and thermal stability of PSA fibers could be improved due to a higher proportion of crystallization. The experimental results of mechanical strength and TG test are coincided with the simulation results. PSA fiber prepared by wet spinning has better thermal stability and mechanical properties than that fabricated by electrospinning. 相似文献
94.
以27份适宜北方生长的李、杏品种为试材,采用SSR分子标记技术对其进行遗传多样性分析,并运用UPGMA聚类分析法,分析了27份试材的亲缘关系,为寒地李、杏种质资源保存和品种选育提供分子生物学依据。结果表明:筛选的25对SSR多态性引物共扩增等位位点245个,其中多态性位点240个,多态性比率为97.96%。每对引物的等位基因数量为4~13,平均值为9.8。有效等位基因数平均值为2.740 5,Shannon′s信息指数平均值为1.052 0,多态性信息含量平均值为0.595 5,表明试材具有较高的遗传多样性。聚类分析结果表明,在遗传相似系数0.612处,27份试材可以分为李和杏两大类群。 相似文献
95.
基于Web of Science的土壤微生物研究文献国际发展态势分析 总被引:2,自引:0,他引:2
在文献调研、专家咨询和文献计量分析的基础上,对国际土壤微生物研究的发展历程进行了回顾,利用文献计量学方法分析了土壤微生物学研究的主要国家和机构状况,分析了近年来相关研究的学科分布以及热点主题内容,分析了国际土壤微生物研究的发展态势和挑战。结果表明:国际土壤微生物研究的学科分布主要集中在土壤科学、环境科学,而且土壤科学、环境科学、生态学、微生物学、农学生物技术应用微生物学的文献数量达到文献总量75.04%,表明这几个学科领域是土壤微生物研究的前沿热点;热点主题主要集中在土壤微生物多样性、生物量、有机质、土壤碳等方面,总结了这些领域的发展趋势和重点研究方向,并根据分析结果,对我国土壤微生物学领域采取的措施、今后发展的方向提出了建议。 相似文献
96.
97.
构建感染草莓镶脉病毒(SVBV)森林草莓的酵母cDNA文库,利用酵母双杂交系统,筛选出与SVBV P1蛋白互作的15种寄主因子。生物信息学分析发现,这15种寄主因子参与茉莉酸途径、泛素化、光合作用、抗病抗逆、蛋白修饰、蛋白运输和氧化还原等多种生物过程。另外,这些寄主因子还具有其他分子功能,包括氧化还原酶活性、蛋白二硫化物异构酶活性和金属离子结合活性等。本研究初步探讨了P1与寄主因子的互作机理,为揭示SVBV侵染森林草莓以及SVBV在寄主中扩展的分子机制提供理论依据。 相似文献
98.
为更好推动农场生态景观建设及相关鼓励政策的制定提供科学依据,对京郊46家果园农场(35家有机果园,11家常规果园)进行调研,以期了解当前经营性农场生态景观现状特征及农场管理者的认知态度、景观偏好和参与生态补偿意愿。结果表明:多数农场建设偏重生产、对景观和生态考虑甚少,景观效果较差;有机农场管理者对生态用地的了解程度显著高于常规农场,但这2类农场的管理者均有通过生态景观建设来获得多种服务的意愿;超过50%的农场管理者偏向于建设花草类生态植被,并倾向于将其建设在农场边界或田块之间以减少占用耕地;90%以上的农场管理者有参与生态补偿的意愿,并希望由政府提供5年以上的资金补贴;农场类型和管理模式影响生态景观建设参与面积的选择,有机农场、企业或合作社经营性农场更能够接受占用超过5%的土地面积建设生态景观。因此,强化农场管理者生态理念和技术培训,以政府作为主要补偿来源提高对花草类生态用地的生态补偿,将有助于推动生态农场生境景观建设和生态系统服务的提升。 相似文献
99.
通过田间试验,对一种植物生长促进菌(PGPR)在水稻上的应用效果作了初步探讨。试验结果表明,PGPR制剂与化肥配合施用对水稻生长发育产生了显著的影响。与单施氮、磷、钾化肥相比,PGPR与化肥处理显著提高了水稻的株高、穗数、穗粒数、千粒重,比单施化肥和不施肥对照分别增产26.0%和53.9%。同时,PGPR处理提高了水稻的根系活力,并对灌浆速率产生了积极的影响。 相似文献
100.
Zhang Wen-yu Xu Jia-hui Zhang Chun-yu Tong Hui-li Li Shu-feng Yan Yun-qin 《东北农业大学学报(英文版)》2021,28(3):38-47
Myoblast differentiation is an essential process during skeletal muscle development. C2 C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro. Dehydrogenase/reductase(SDR family) member 3(DHRS3) is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol. Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation. However, the effect of DHRS3 on mouse muscle cell differentiation was unclear. The objective of current study was to determine if DHRS3 affected muscle cell differentiation, and if DHRS3 was involved in muscle regeneration. Protein expression was determined by western blot and immunofluorescence analysis. The activation and inhibition of DHRS3 increased and decreased C2 C12 myoblast differentiation respectively, which indicated that DHRS3 could affect C2 C12 myoblast differentiation. DHRS3 expression was significantly changed during muscle regeneration, with the regeneration of muscle injury, the expression of DHRS3 tended to increase first and then decrease. It suggested that DHRS3 might be involved in muscle regeneration. In summary, this study confirmed the involvement of DHRS3 in C2 C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development. 相似文献