A case of Meropenem as a novel antibacterial agent to suppress and eliminate Agrobacterium tumefaciens in the Agrobacterium-mediated transformation of orchid protocorm-like bodies （PLBs） has been reported in this ar...A case of Meropenem as a novel antibacterial agent to suppress and eliminate Agrobacterium tumefaciens in the Agrobacterium-mediated transformation of orchid protocorm-like bodies （PLBs） has been reported in this article. The in vitro activities of meropenem and four comparator antibacterial agents against three Agrobacterium tumefaciens strains, LBA4404, EHA101, and GV3101, were assessed. In addition, the effect of meropenem on the growth of Dendrobium phalaenopsis PLBs was determined. Compared with other commonly used antibiotics （including ampicillin, carbenicillin, cefotaxime, and cefoperazone）, meropenem showed the highest activity in suppressing all tested A. tumefaciens strains （minimum inhibitory concentration [MIC] 〈 0.5 mg L^-1, which is equal to minimum bactericidal concentration [MBC]）. Meropenem, at all tested concentrations, except for 10 mg L^-1 concentration, had little negative effect on the growth of orchid tissues. The A. tumefaciens strain EHA101 in genetic transformation with vector plG121Hm in infected PLBs of the orchid was visually undetectable after a two-month subculture in 1/2 MS medium with 50 mg L^-1 meropenem and 25 mg L^-1 hygromacin. The expression and incorporation of the transgenes were confirmed by GUS histochemical assay and PCR analysis. Meropenem may be an alternative antibiotic for the effective suppression of A. tumefaciens in genetic transformation.展开更多
介绍了SoPC(System on a Programmable Chip)系统的概念和特点,给出了基于PLB总线的异步串行通信(UART)IP核的硬件设计和实现。通过将设计好的UART IP核集成到SoPC系统中加以验证,证明了所设计的UARTIP核可以正常工作。该设计方案为其...介绍了SoPC(System on a Programmable Chip)系统的概念和特点,给出了基于PLB总线的异步串行通信(UART)IP核的硬件设计和实现。通过将设计好的UART IP核集成到SoPC系统中加以验证,证明了所设计的UARTIP核可以正常工作。该设计方案为其他基于SoPC系统IP核的开发提供了一定的参考。展开更多
本文对连接调压器的电源保险丝在电源闭合的瞬间出现不规律的熔断问题,结合动态电路知识给出了理论解答。对讲授《电路》课程的教师在将PBL(Problem based learning)学习模式引入教学时有一定的借鉴作用。提出在《电路》课程中开展PBL...本文对连接调压器的电源保险丝在电源闭合的瞬间出现不规律的熔断问题,结合动态电路知识给出了理论解答。对讲授《电路》课程的教师在将PBL(Problem based learning)学习模式引入教学时有一定的借鉴作用。提出在《电路》课程中开展PBL学习模式对巩固学生的电路理论知识,提高学生分析问题与解决问题能力有极大的促进作用,应在教学过程中针对不同教学内容,以开放实验的形式展开实践活动。展开更多
文摘A case of Meropenem as a novel antibacterial agent to suppress and eliminate Agrobacterium tumefaciens in the Agrobacterium-mediated transformation of orchid protocorm-like bodies （PLBs） has been reported in this article. The in vitro activities of meropenem and four comparator antibacterial agents against three Agrobacterium tumefaciens strains, LBA4404, EHA101, and GV3101, were assessed. In addition, the effect of meropenem on the growth of Dendrobium phalaenopsis PLBs was determined. Compared with other commonly used antibiotics （including ampicillin, carbenicillin, cefotaxime, and cefoperazone）, meropenem showed the highest activity in suppressing all tested A. tumefaciens strains （minimum inhibitory concentration [MIC] 〈 0.5 mg L^-1, which is equal to minimum bactericidal concentration [MBC]）. Meropenem, at all tested concentrations, except for 10 mg L^-1 concentration, had little negative effect on the growth of orchid tissues. The A. tumefaciens strain EHA101 in genetic transformation with vector plG121Hm in infected PLBs of the orchid was visually undetectable after a two-month subculture in 1/2 MS medium with 50 mg L^-1 meropenem and 25 mg L^-1 hygromacin. The expression and incorporation of the transgenes were confirmed by GUS histochemical assay and PCR analysis. Meropenem may be an alternative antibiotic for the effective suppression of A. tumefaciens in genetic transformation.
文摘介绍了SoPC(System on a Programmable Chip)系统的概念和特点,给出了基于PLB总线的异步串行通信(UART)IP核的硬件设计和实现。通过将设计好的UART IP核集成到SoPC系统中加以验证,证明了所设计的UARTIP核可以正常工作。该设计方案为其他基于SoPC系统IP核的开发提供了一定的参考。
文摘本文对连接调压器的电源保险丝在电源闭合的瞬间出现不规律的熔断问题,结合动态电路知识给出了理论解答。对讲授《电路》课程的教师在将PBL(Problem based learning)学习模式引入教学时有一定的借鉴作用。提出在《电路》课程中开展PBL学习模式对巩固学生的电路理论知识,提高学生分析问题与解决问题能力有极大的促进作用,应在教学过程中针对不同教学内容,以开放实验的形式展开实践活动。
