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81.
82.
将编码人单核细胞趋化蛋白-1(MCP-1)的基因亚克隆到大肠杆菌表达载体pEX31A中,在大肠杆菌中表达出MS2/MCP-1融合蛋0白,该表达产物约占菌体总蛋白的15%左右,Westernblot检测表明,表达产物可与MCP-1抗体特异反应。采用琼脂糖平板法进行活性测定表明,表达产物具有明显的单核细胞趋化活性,说明N端融合一段细菌蛋白对MCP-1有无趋化活性可能没有影响。 相似文献
83.
Wen Wang Ai-hua Liu Shi-ying Lin Hong Lan Bing Su De-wen Xie Li-ming Shi 《Biochemical genetics》1994,32(9-10):371-378
mtDNA genotypes of six domestic horses (three adult short horses whose heights are under 1 m and three common domestic horses) from a small region of 15 km2 in Malipo county of Yunnan province of China were investigated by the technique of restriction fragment length polymorphism (RFLP) with 16 restriction endonucleases which recognize 6-bp sequences. An average of 56 fragments for an individual was obtained. Unlike other domestic animals, this population of horses exhibits high mtDNA genetic diversity. Each of the six horses has a specific mtDNA genotype showing a pattern of multiple maternal origins, as suggested by fossil and literature records. We think the population of horses is an amazing seed-resource pool of horses and hence deserves to be paid more attention from the view of conservation genetics. However, it is also remarkable that we did not find any typical mtDNA genetic markers which would discriminate between short horses and common domestic horses. 相似文献
84.
Soo Wan Nam Byung Moon Kim Bong Hyun Chung Dae Ook Kang Jong Seog Ahn 《Biotechnology letters》1994,16(9):897-902
Summary For the secretion of human lipocortin-1 (LC-1) in yeast, a expression and secretion vector was constructed by using the promoter and signal sequence of glucoamylase gene (STA1) of Saccharomyces diastaticus. After the cDNA of human LC-1 was ligated with the secretion vector, the resulting hybrid plasmid was transformed into S. diastaticus. When the recombinant S. diastaticus was cultivated in YPD medium, LC-1 was expressed and secreted into the extracellular medium, yielding LC-1 protein at a concentration of 2.5 g/mL. 相似文献
85.
PalaeoniscidaeVogt,l852Weixiniscusgen.nov.TypespeeiesWcixiniscusmicrolepis.Genericdiagnovi8Small'palaeoniscidofelongate-fusiformbody.Dorsalfinlong-based,opposingt0thespacebetweenpelvicandanalfins.Pelvicfinwithrela-tivelylongbase,nearertoanalfinthant0pectorals.Caudalfinheterocerca1,deepcleft,upper1obelongerthanlowerlobe-Fin-rays0fallfinscompletelyandsparselysegmented,brancheddistally.Fin-'fulcrapresentontheuppercaudallobe.Postorbitalpartofmaxilliaratherexpanded,ofpalaeoniscoidshape.Suspetis… 相似文献
86.
Genetic transformation and plant regeneration of watermelon using Agrobacterium tumefaciens 总被引:1,自引:0,他引:1
Adventitious shoots formed on the proximal cut edges of different cotyledonary explants of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai; cvs. Sweet Gem and Gold Medal] cultured on Murashige and Skoog's (MS) medium with 1 mgl-1 6-benzyladenine (BA). Light (16-h photoperiod, about 7 Wm-2 cool-white fluorescent lamps) was essential for shoot formation. To obtain transformed plants, cotyledonary explants of Sweet Gem were cocultured with Agrobacterium tumefaciens LBA4404, a disarmed strain harboring a binary vector pBI121 carrying the CaMV 35S promoter--glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker, for 48 h on MS medium with 1 mgl-1 BA and 200 M -hydroxyacetosyringone. After 48 h of culture, explants were transferred to medium with 1 mgl-1 BA 250 mgl-1 carbenicillin, and 100 mgl-1 kanamycin and cultured in the light. Adventitious shoots formed on the explants after 4 weeks of culture. When subjected to GUS histochemical assay, young leaves obtained from the shoots showed a positive response at a frequency of up to 16%. Preculturing cotyledonary explants on MS medium with 1 mgl-1 BA for 5 d enhanced the competence of the cells to be transformed by Agrobacterium. Southern blot analysis confirmed that the GUS gene was incorporated into the genomic DNA of the GUS-positive regenerants. The transformed plants were grown to maturity. 相似文献
87.
Summary Secretion of invertase and inulinase produced by recombinant Saccharomyces cerevisiae cells were investigated under derepression conditions of GALI promoter. Secreted invertase mainly localized in the periplasmic space, but most of inulinase was found in the extracellular culture medium. This high level of extracellular secretion of inulinase was not dependent on the growth phase in which derepression of GALI promoter occurs. Our results indicate that the inulinase polypeptide itself may have a function for the protein secretion into the culture medium. 相似文献
88.
Summary Plant hairy root cultures of Lithospermum erythrorhizon were carried out to produce shikonin derivatives by employing in situ extraction with n-hexadecane in a shake flask and a bubble column bioreactor. Over 95 % shikonin produced was recovered in the n-hexadecane layer. In flask cultures the maximum concentration of shikonin with n-hexadecane extraction was 3 times higher than that obtained without extraction. In the two phase bubble column reactor, 572.6 mg/L of shikonin and 15.6 g/L of dry cell mass were obtained after 54 days. Shikonin was produced at a constant level of 10.6 mg/L day during this period. 相似文献
89.
RGDS肽对大鼠主动脉球囊内膜剥脱后血管壁增殖的影响 总被引:1,自引:0,他引:1
在大鼠主动脉球囊内膜剥脱术后血管壁细胞过度增殖模型上,用合成的血小板膜纤维蛋白原受体(glycoproteinⅡb/Ⅲacomplex,GPⅡb/Ⅲa)拮抗剂RGDS(Arg-Gly-Asp-Ser,50μmol·kg-1·d-1)治疗可有效地抑制损伤血管壁的细胞计数增加和内膜增厚以及血管平滑肌细胞增殖,显著降低其血管组织3H-TdR和3H-Leu的参入增加程度。实验结果提示RGDS肽作为血管成型术的辅佐剂,对于防治血管再狭窄可能具有潜在的临床应用前景。 相似文献
90.
腹腔注射链脲佐霉素(65mg/kg)诱发Wistar大鼠糖尿病。糖尿病发病4周后,向饲料中加尼群地平(30mg·kg-1·d-1)。结果表明,糖尿病4周时大鼠心室舒张功能首先受损,8周后心室舒张和收缩功能均明显受累。尼群地平处理对糖尿病大鼠的心肌收缩性有一定的改善作用。提示尼群地平对大鼠糖尿病性心肌病有一定有益作用。 相似文献