期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
平板霉素和平板素及其衍生物的生物合成、全合成与半合成研究进展
1
作者 田凯 邓友超 +2 位作者 李玉玲 段燕文 黄勇 《有机化学》 SCIE CAS CSCD 北大核心 2018年第9期2348-2362,共15页
多重耐药菌感染是全球最严重的公共卫生危机之一.平板霉素和平板素是针对耐甲氧西林金黄色葡萄球菌和耐万古霉素肠球菌等多种革兰氏阳性菌,均有优异抗菌活性的药物先导物.由于其优异的生物活性和新奇的分子结构,多个研究小组在过去的十... 多重耐药菌感染是全球最严重的公共卫生危机之一.平板霉素和平板素是针对耐甲氧西林金黄色葡萄球菌和耐万古霉素肠球菌等多种革兰氏阳性菌,均有优异抗菌活性的药物先导物.由于其优异的生物活性和新奇的分子结构,多个研究小组在过去的十余年里,对平板霉素和平板素的生物合成、全合成和半合成进行了系统研究.这些研究不仅揭示了微生物药物发现的新高通量筛选策略,而且还发现负责平板霉素和平板素生物合成基因簇,并表征了多个独特的生物合成酶,例如新颖的细菌二萜合酶和硫代羧酸的生物合成酶.通过对上述研究产生的一系列平板霉素和平板素类似物及生物活性测试,揭示了这些化合物的构效关系.平板霉素和平板素的研究是结合有机合成与生物合成,加速微生物天然产物药物发现和开发的范例.综述了平板霉素和平板素的近期研究进展. 展开更多
关键词 平板 平板素 抗生 生物合成 全合成 半合成
原文传递
脂肪酸合成抑制剂平板霉素的开发
2
作者 王林婧 胡海峰 《世界临床药物》 CAS 2011年第12期738-741,共4页
平板霉素为平板链球菌(Streptomyces platensis)的代谢产物,其独特的化学结构和良好的抗菌活性引人关注。平板素及其他系列同类物的开发,改善了平板霉素的体内药动学不稳定性。本文综述平板霉素的抗菌原理与活性、同类物开发和基因改造。
关键词 脂肪酸合成抑制剂 平板 平板素 抗生 生物合成 药物开发
原文传递
Slope analysis based on local strength reduction method and variable-modulus elasto-plastic model 被引量:4
3
作者 杨光华 钟志辉 +3 位作者 傅旭东 张玉成 温勇 张明飞 《Journal of Central South University》 SCIE EI CAS 2014年第5期2041-2050,共10页
Employing an ideal elasto-plastic model,the typically used strength reduction method reduced the strength of all soil elements of a slope.Therefore,this method was called the global strength reduction method(GSRM).How... Employing an ideal elasto-plastic model,the typically used strength reduction method reduced the strength of all soil elements of a slope.Therefore,this method was called the global strength reduction method(GSRM).However,the deformation field obtained by GSRM could not reflect the real deformation of a slope when the slope became unstable.For most slopes,failure occurs once the strength of some regional soil is sufficiently weakened; thus,the local strength reduction method(LSRM)was proposed to analyze slope stability.In contrast with GSRM,LSRM only reduces the strength of local soil,while the strength of other soil remains unchanged.Therefore,deformation by LSRM is more reasonable than that by GSRM.In addition,the accuracy of the slope's deformation depends on the constitutive model to a large degree,and the variable-modulus elasto-plastic model was thus adopted.This constitutive model was an improvement of the Duncan–Chang model,which modified soil's deformation modulus according to stress level,and it thus better reflected the plastic feature of soil.Most importantly,the parameters of the variable-modulus elasto-plastic model could be determined through in-situ tests,and parameters determination by plate loading test and pressuremeter test were introduced.Therefore,it is easy to put this model into practice.Finally,LSRM and the variable-modulus elasto-plastic model were used to analyze Egongdai ancient landslide.Safety factor,deformation field,and optimal reinforcement measures for Egongdai ancient landslide were obtained based on the proposed method. 展开更多
关键词 slope stability local strength reduction method variable-modulus elasto-plastic model in-situ test
下载PDF
Autostereoscopic 3D flat panel display using an LCD-pixel-associated parallax barrier 被引量:1
4
作者 陈恩果 郭太良 《Optoelectronics Letters》 EI 2014年第3期191-193,共3页
This letter reports an autostereoscopic three-dimensional (3D) fiat panel display system employing a newly designed LCD-pixel-associated parallax barrier (LPB). The battler's parameters can be conveniently determ... This letter reports an autostereoscopic three-dimensional (3D) fiat panel display system employing a newly designed LCD-pixel-associated parallax barrier (LPB). The battler's parameters can be conveniently determined by the LCD pixels and can help to greatly simplify the conventional design. The optical system of the proposed 3D display is built and simulated to verify the design. For further experimental demonstration, a 508-mm autostereoscopic 3D displayprototype is developed and it presents good stereoscopic images. Experimental results agree well wlth the simulation, which reveals a strong potential for 3D display applications. 展开更多
关键词 Flat panel displays Geometrical optics Liquid crystal displays Optical systems Three dimensional
原文传递
Accurate assessment of antibiotic susceptibility and screening resistant strains of a bacterial population by linear gradient plate 被引量:4
5
作者 LIU YuQing LI JingRan +8 位作者 DU JiaFa HU Ming BAI Hua QI Jing GAO Chao WEI TianTian SU Hong JIN JianLing GAO PeiJi 《Science China(Life Sciences)》 SCIE CAS 2011年第10期953-960,共8页
The dynamics of a bacterial population exposed to the minimum inhibitory concentration (MIC) of an antibiotic is an important issue in pharmacological research. Therefore, a novel antibiotic susceptibility test is u... The dynamics of a bacterial population exposed to the minimum inhibitory concentration (MIC) of an antibiotic is an important issue in pharmacological research. Therefore, a novel antibiotic susceptibility test is urgently needed that can both precisely determine the MIC and accurately select antibiotic-resistant strains from clinical bacterial populations. For this purpose, we developed a method based on Fick's laws of diffusion using agar plates containing a linear gradient of antibiotic. The gradient plate contained two layers. The bottom layer consisted of 15 mL agar containing the appropriate concentration of enrofloxacin and allowed to harden in the form of a wedge with the plate slanted such that the entire bottom was just covered. The upper layer consisted of 15 mL plain nutrient agar added with the plate held in the horizontal position. After allowing vertical diffusion of the drug from the bottom agar layer for 12 h, the enrofloxacin concentration was diluted in proportion to the ratio of the agar layer thicknesses. The uniform linear concentration gradient was verified by measuring the enrofloxacin concentration on the agar surface. When heavy bacterial suspensions were spread on the agar surface and incubated for more than 12 h, only resistant cells were able to form colonies beyond the boundary of confluent growth of susceptible cells. In this way, the true MIC of enrofloxacin was determined. The MICs obtained using this linear gradient plate were consistent with those obtained using conventional antibiotic susceptibility tests. Discrete colonies were then spread onto a gradient plate with higher antibiotic concentrations; the boundary line increased significantly, and gene mutations conferring resistance were identified. This new method enables the rapid identification of resistant strains in the bacterial population. Use of the linear gradient plate can easily identify the precise MIC and reveal the dynamic differentiation of bacteria near the MIC. This method allows the study of genetic and physiological characteristics of individual strains, and may be useful for early warning of antibiotic resistance that may occur after use of certain antirnicrobial agents, and guide clinical treatment. 展开更多
关键词 linear gradient plate E. coli ENROFLOXACIN MIC resistant strain
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部