Objective: To expound the mechanism of nerve growth factor (NGF) to protectspinal cord against injury. Methods: Forty-five rats with 10 g X 2. 5 cm impact T_8 spinal cordinjury (SCI) were divided into 3 groups. The ex...Objective: To expound the mechanism of nerve growth factor (NGF) to protectspinal cord against injury. Methods: Forty-five rats with 10 g X 2. 5 cm impact T_8 spinal cordinjury (SCI) were divided into 3 groups. The experimental animals received 60 g NGF purified frombovine seminal plasma instantly, 1, 2, 4 h after in jury and an equal volume of normal saline wasgiven to the control group at the same time. The c-fos mRNA levels were detected by in situhybridization. Results: The results showed no evident c-fos expression in normal control group. Thec-fos expression increased markedly in damaged neurons. The peak value of c-fos mRNA arose at 1 h,and c-fos levels in NGF group reduced evidently. Conclusion: NGF could inhibit c-fos expression. Itmay serve as one of the action mechanisms of NGF to protect spinal cord against injury.展开更多
植物花器官的发育和开花是植物生殖发育中最重要的过程,植物在长期的进化过程中产生了春化(低温)途径、自主途径、光周期途径以及不依赖于光温环境条件的赤霉素信号途径来适应多变的环境和调控植物开花过程。本文综述了模式植物拟南芥中...植物花器官的发育和开花是植物生殖发育中最重要的过程,植物在长期的进化过程中产生了春化(低温)途径、自主途径、光周期途径以及不依赖于光温环境条件的赤霉素信号途径来适应多变的环境和调控植物开花过程。本文综述了模式植物拟南芥中由LEAFY(LFY)、CONSTANS(CO)、FLOWERING LOCUSC(FLC)、FLOW ERING LOCUS T(FT)和SUPPRESSOR OF OVEREXPRESSION OF CO1(SOC1)等基因构成的双子叶植物响应光温条件变化的开花调控网络;以及大麦、小麦中由VERNALIZATION1(VRN1)、VRN2、ODD-SOC2(OS2)和拟南芥CO、FT同源基因构成的禾本科植物开花调控网络。其中最重要的是转录调控因子MADS-box基因FLC、SOC1、VRN1和OS2,并发现组蛋白的乙酰化/脱乙酰化,赖氨酸的甲基化/脱甲基化在调控FLC、VRN1染色质活性状态及基因表达,从而产生开花控制的机理。这些研究发现将有助于对具有重要经济价值的单双子叶植物,通过生物技术手段改良其品种特性以应对非生物逆境,特别是低温胁迫的指导。展开更多
文摘Objective: To expound the mechanism of nerve growth factor (NGF) to protectspinal cord against injury. Methods: Forty-five rats with 10 g X 2. 5 cm impact T_8 spinal cordinjury (SCI) were divided into 3 groups. The experimental animals received 60 g NGF purified frombovine seminal plasma instantly, 1, 2, 4 h after in jury and an equal volume of normal saline wasgiven to the control group at the same time. The c-fos mRNA levels were detected by in situhybridization. Results: The results showed no evident c-fos expression in normal control group. Thec-fos expression increased markedly in damaged neurons. The peak value of c-fos mRNA arose at 1 h,and c-fos levels in NGF group reduced evidently. Conclusion: NGF could inhibit c-fos expression. Itmay serve as one of the action mechanisms of NGF to protect spinal cord against injury.
文摘植物花器官的发育和开花是植物生殖发育中最重要的过程,植物在长期的进化过程中产生了春化(低温)途径、自主途径、光周期途径以及不依赖于光温环境条件的赤霉素信号途径来适应多变的环境和调控植物开花过程。本文综述了模式植物拟南芥中由LEAFY(LFY)、CONSTANS(CO)、FLOWERING LOCUSC(FLC)、FLOW ERING LOCUS T(FT)和SUPPRESSOR OF OVEREXPRESSION OF CO1(SOC1)等基因构成的双子叶植物响应光温条件变化的开花调控网络;以及大麦、小麦中由VERNALIZATION1(VRN1)、VRN2、ODD-SOC2(OS2)和拟南芥CO、FT同源基因构成的禾本科植物开花调控网络。其中最重要的是转录调控因子MADS-box基因FLC、SOC1、VRN1和OS2,并发现组蛋白的乙酰化/脱乙酰化,赖氨酸的甲基化/脱甲基化在调控FLC、VRN1染色质活性状态及基因表达,从而产生开花控制的机理。这些研究发现将有助于对具有重要经济价值的单双子叶植物,通过生物技术手段改良其品种特性以应对非生物逆境,特别是低温胁迫的指导。