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121.
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   
122.
籼粳分化是水稻遗传分化的主流,而明晰水稻的起源演化和亲缘关系,对合理有效地利用种质资源和品种改良具有重要的参考价值.从形态学、生物化学和分子遗传学的角度阐述了国内外在不同时期对水稻籼粳分化相关研究取得的成果,总结了人们对于籼粳分化相关理论的认识,并对该领域研究存在的不足和发展趋势进行探讨.  相似文献   
123.
To understand the genetic diversity and indica-japonica differentiation in Bangladesh rice varieties, a total of 151 accessions of rice varieties mostly Bangladesh traditional varieties including Aus, Boro, broadcast Aman, transplant Aman and Rayada varietal groups were genotyped using 47 rice nuclear SSRs. As a result, three distinct groups were detected by cluster analysis, corresponding to indica, Aus and japonica rice. Among deepwater rice varieties analyzed some having particular morphological features that mainly corresponded to the japonica varietal group. Some small seeded and aromatic varieties from Bangladesh also corresponded to the japonica varietal group. This research for the first time establishes that the japonica varietal group is a prominent component of traditional varieties in Bangladesh, particularly in deepwater areas.  相似文献   
124.
In this study,the seeds of wild Petunia Juss.were used as explants to investigate the optimal condition for tissue culture.Several different kinds and concentrations of growth regulators were adopted to produce more multiple bud clumps,callus or roots in this study.The experiments may provide experimental foundation for the rapid propagation technology and establishment of tissue culture system for wild Petunia Juss.  相似文献   
125.
山新杨高效组培再生体系的建立   总被引:2,自引:0,他引:2  
王红蕾 《北方园艺》2010,(13):174-175
以山新杨(P.davidiana×P.bolleana)叶片为外植体,1/2MS为基本培养基,对适合山新杨叶片再生的生长调节剂6-BA和NAA进行研究。结果表明:适宜山新杨叶片分化培养基是1/2MS+NAA 0.05 mg/L+6-BA 0.5 mg/L;继代抽茎培养基是1/2MS+NAA 0.08 mg/L+6-BA 0.1 mg/L;最佳生根培养基是1/2MS+IBA 0.3 mg/L。  相似文献   
126.
目前,我国高校教师群体内部不同程度地出现了经济收入和权利地位等待遇分化趋向。高校教师的待遇分化主要体现在“官民”之别、文理之差和资历之异上,其源于高校管理“行政化”、学科分化和个体资本互化等因素合力作用的结果。可以通过“去行政化”、完善考评分配制度等措施来缩小高校内部不同群体间的待遇分化。  相似文献   
127.
Citrus tristeza virus (CTV), the most devastating viral pathogen in citrus, causes tremendous economic losses to citrus industry worldwide. The CTV isolates exhibit variable pathogenicities on their ho...  相似文献   
128.
129.
The Ecological Concept of Costs of Induced Systemic Resistance (ISR)   总被引:11,自引:0,他引:11  
Plant defence is thought to provide benefits for the defended plants. Theoretical concepts must, therefore, explain why there is variation in defensive traits, which naively might be assumed to be present constitutively in fixed high amounts. Explanations are mainly based on the assumption of fitness costs. Investment in defence is thought to reduce the fitness of plants in enemy-free environments. Fitness costs often result from allocation costs, i.e. allocation of limited resources to defence, which then cannot be used for growth or other fitness-relevant processes. This theoretical concept can provide a useful tool for the interpretation of induced plant responses against pathogens, named induced systemic (or systemic acquired) resistance (ISR or SAR). Phenotypic plasticity, leading to induced responses, might have evolved mainly to reduce costs, since investment in defence is restricted to situations actually requiring defence. ISR can incur allocation costs and other, indirect costs, which ultimately may lead to fitness costs. Evolution of any defensive trait depends on both what a plant ideally 'should do and what it actually 'is able to do. Costs of defence constrain its expression. This might have important influences on the evolution of plant defensive traits, as well as on the exploitation of natural defences in agricultural crop protection.  相似文献   
130.
胚胎干细胞向神经细胞定向诱导分化方法的研究进展   总被引:2,自引:0,他引:2  
胚胎干细胞具有自我更新和多向分化潜能,有望成为治疗神经系统疾病重要的种子细胞来源。如何高效地诱导胚胎干细胞向特定神经细胞分化是目前研究的热点。本文就胚胎干细胞定向分化成神经细胞的3种方法:RA诱导法、谱系选择法和SDIA法及其移植研究做一综述。  相似文献   
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