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31.
In ribosomal protein S12 mutant or L24 mutant the expression of λN gene was depressed at translational level. To study its
mechanism the λN gene region of λN -lacZ gene fusion was trimmed from its 5′ end to 3′ end with DNA exonuclease III (DNA cxoIII) in order to alter the TIR (translational
initiation region) and the ding region of λN gene. After DNA sequencing 23 species of different λN-lacZ fused genes were obtained.
The β-galactosidase activities of these deletants in ribosomal protein mutant were compared with that in wild type strain.
The result indicated that (i) S12 mutant could affect 305 subunit’s binding to the TIR of λN gene messenger and cause the
difficulty in forming 30s initiation complex and then decrease the efficiency of translational initiation; (ii) in S12 mutant
the coding region of λN gene alw affected the expression λN gene; (iii) in L24 mutant the inhibition of λN gene expression
was not related to translational initiation and the 5′ end of the coding region of λN gene, but related to the 3′ end of λN
gene.
Project supported by the National Natural Science Foundation of China (Grant Nos. 39480014, 39570162) and Chinese Academy
of Sciences. 相似文献
32.
Rapid and reliable detection of 11 food-borne pathogens using thin-film biosensor chips 总被引:1,自引:0,他引:1
Sulan Bai Jinyi Zhao Yaochuan Zhang Wensheng Huang Shi Xu Haodong Chen Liu-Min Fan Ying Chen Xing Wang Deng 《Applied microbiology and biotechnology》2010,86(3):983-990
Traditional methods for identifying food-borne pathogens are time-consuming and laborious, so it is necessary to develop innovative
methods for the rapid identification of food-borne pathogens. Here, we report the development of silicon-based optical thin-film
biosensor chips for sensitive detection of 11 food-borne pathogens. Briefly, aldehyde-labeled probes were arrayed and covalently
attached to a hydrazine-derivatized chip surface, and then, biotinylated polymerase chain reaction (PCR) amplicons were hybridized
with the probes. After washing and brief incubation with an antibiotin immunoglobulin G–horseradish peroxidase conjugate and
a precipitable horseradish peroxidase substrate, biotinylated chains bound to the probes were visualized as a color change
on the chip surface (gold to blue/purple). Highly sensitive and accurate examination of PCR fragment targets can be completed
within 30 min. This assay is extremely robust, sensitive, specific, and economical and can be adapted to different throughputs.
Thus, a rapid, sensitive, and reliable technique for detecting 11 food-borne pathogens was successfully developed. 相似文献
33.
34.
Guozhi Tang Zongxing Qiu Xianfeng Lin Wentao Li Lei Zhu Shaohua Li Haodong Li Lisha Wang Li Chen Jim Z. Wu Wengang Yang 《Bioorganic & medicinal chemistry letters》2010,20(12):3507-3510
A novel class of HA inhibitors (4a) was identified based on ligand similarity search of known HA inhibitors. Parallel synthesis and further structural modifications resulted in 1-phenyl-cyclopentanecarboxylic acid (4-cyano-phenyl)-methyl-amide 4t as a potent and selective inhibitor to phylogenetic H1 influenza viruses with an EC50 of 98 nM against H1N1 A/Weiss/43 strain and over 1000-fold selectivity against host MDCK cells. 相似文献
35.
目的:探讨细胞内铜/锌超氧化物岐化酶(copper zinc superoxide dismutase,Cu/Zn-SOD,SOD-1)在人胸主动脉夹层(humanthoracic aortic dissection,hTAD)中的表达情况及其在hTAD中的可能作用。方法:蛋白质印迹法(Western blot,WB)检测SOD-1在TAD和正常人胸主动脉(NA)中膜组织中的表达情况,免疫组织化学染色(immunohistochemistry,IHC)验证SOD-1在动脉壁中的表达和定位。结果:蛋白质印迹和免疫组化染色均显示SOD-1在TAD组表达量较NA组减低(P<0.05);免疫组化染色进一步显示,SOD-1主要位于主动脉壁中膜平滑肌细胞的胞质内,其在夹层主动脉壁中膜撕开处表达缺失。结论:SOD-1在TAD中表达量减少,可能由于参与氧化应激引起的脂质过氧化和炎症反应,以及细胞外基质(extracellular matrix,ECM)的降解等机制所致。 相似文献
36.
目的:探讨胸主动脉壁中α-平滑肌肌动蛋白(α-SMA)的表达与胸主动脉夹层(TAD)的关系。方法:采集人TAD的动脉壁组织和正常人胸主动脉壁组织,采用Western Blotting和免疫组织化学方法检测α-SMA在组织中的表达程度。结果:在DA组中,α-SMA的表达明显减少,血管平滑肌细胞(VSMC)以增殖表型为主。结论α-SMA的减少主要发生在血管中膜层的VSMC中,细胞发生表型变化,导致中膜弹性变差,发生夹层病变。因此,α-SMA可能在TAD的发病中具有重要作用,值得进一步深入探讨。 相似文献
37.
目的:探讨预防关节置换术后下肢深静脉血栓形成的有效护理对策.方法:针对下肢深静脉血栓形成的高危因素,对行人工关节置换的患者行预防性药物,物理预防以及系统性功能锻炼.结果:181例术后患者中有41例发生静脉血栓,发生率为22.2%.治疗后均痊愈出院.结论:细致的护理和有效的措施是预防下肢静脉血栓的关键,积极的治疗和护理可避免深静脉血栓的形成后的严重的并发症. 相似文献
38.
珍珠菜属四种植物的核型分析 总被引:2,自引:0,他引:2
对珍珠菜属4种植物的核型进行了研究。结果表明,叶头过路黄(Lysimachia phyllocephala Hand.-Mazz.)的核型为:2n=2x=24=2m 6sm 2st 14t,茂汶过路黄(L. stellarioidesHand.-Mazz.)的核型为:2n=2x=24=4m 2sm 18t,均属首次报道。矮桃(L. clethroidesDuby)的核型为:2n=2x=24=16m 8sm(1SAT),腺药珍珠菜(L. stenosepala Hemsl.)的核型为:2n=2x=24=10m 12sm 2st,与前人报道的有所不同。还对该属已报道的23种植物的核型进行了比较。 相似文献
39.
Chun-yu YIN Hong-zhou LU Wei-ming JIANG Maria Pia De Pasquale Yue-kai HU Xiao-zhang PAN Xin-hua WENG Richard T. D'Aquila Yi-Wei TANG 《Virologica Sinica》2007,22(3):212-217
Illegally paid blood donation was a risk factor for HIV acquisition exclusively in Henan and Hubei Provinces of China,and not in Shanghai.Nucleotide sequences in the gag and env genes of HIV-1 were compared between isolates from Henan and Shanghai regions of China to test whether an expected higher degree of a common source of infections from this unique blood donation transmission risk would be evident as decreased variation among Henan isolates in an exploratory cross-sectional analysis.Among 38 isolates studied,23 of 23(100%)from Henan and 8 of 15(54%)from Shanghai were subtype B.In addition,fewer sequence differences were found in gp41 of subtype B isolates from Henan than from Shanghai isolates.Further studies with additional controls are therefore warranted to confirm the role of the degree of a common source of infections in differences in HIV variation across populations. 相似文献
40.