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1.
Generation of small mutation in large genomic fragments by homologous recombination: description of the technique and examples of its use 总被引:2,自引:0,他引:2 下载免费PDF全文
M Tripodi S Perfumo R Ali L Amicone C Abbott R Cortese 《Nucleic acids research》1990,18(21):6247-6251
We have developed a technique of homologous recombination in bacteria which allows the mutagenesis of large genomic fragments cloned in cosmids. The desired mutation is first introduced into a plasmid clone and is then transferred to the appropriate cosmid clone by the means of double antibiotic selection coupled with phenotypic selection. We describe three different types of construct made by this technique. 相似文献
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Giuliano Callaini Maria Giovanna Riparbelli Marcella Cintorino Sergio Antonio Tripodi Giorgio Bianciardi Piero Tosi Romano Dallai 《Biology of the cell / under the auspices of the European Cell Biology Organization》1994,81(1):39-45
Summary— Immunofluorescence and immunoelectron microscopy indicated that the antibody raised against the nuclear antigen Ki-67 of mammalian cells recognized antigenic determinants of early Drosophila embryos, localized on the outside of the nuclear envelope. Hence, the nuclear envelope of Drosophila appears to share a similar epitope with the chromosome scaffold of mitotic mammalian cells. With the progression of mitosis the antigen persisted around the mitotic spindle region and was also found in the pole regions at metaphase and anaphase. The antibody also stained the equatorial regions of the spindles from anaphase to late telophase. The antibody may therefore be used as a biochemical marker of the nuclear envelope for studying nuclear membrane biogenesis and behavior during the mitotic divisions of the Drosophila embryo. 相似文献
4.
R Utili M F Tripodi C O Abernathy H J Zimmerman J Gillespie 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1992,199(1):49-53
The present study has demonstrated that tauroursodeoxycholate (TUDC), but not taurocholate, can reverse chlorpromazine (CPZ)-induced cholestasis in the isolated perfused rat liver. At an infusion rate of 1.5 mumol/min, TUDC led to restoration of bile flow in the perfused rat liver made cholestatic by the addition of 250 microM CPZ. This reversal was accompanied by an increased excretion of CPZ and its metabolites. A higher infusion rate of 5.0 mumols TUDC/min, however, led to only a transient increase in bile flow and to no increase in CPZ excretion. In contrast to the effects of TUDC, infusion of taurocholate led to an exacerbation of CPZ-induced cholestasis. The differences in the efficacy of the two bile salts may be due to their relative detergent (hydrophobic) properties. 相似文献
5.
【背景】杨树溃疡病是一种主要由葡萄座腔菌引起的杨树枝干病害,危害严重。前期从杨树中分离到一株内生拮抗细菌N6-34,研究表明该菌株拮抗效果好,对多种植物病原菌均有较强的拮抗作用。【目的】对拮抗细菌N6-34产生的抗菌活性物质进行分离纯化,并鉴定了活性物质组分的结构。【方法】通过硫酸铵盐析、甲醇抽提、分子筛、高效液相色谱等方法分离纯化N6-34菌株的抗菌活性物质,并对其进行结构鉴定。【结果】N6-34菌株发酵液经多步分离纯化,共获得14个组分,其中有13个组分具有抗菌活性,经一级质谱分析,获得了13种抗菌活性组分的分子量;经二级质谱分析,将13种抗菌活性物质鉴定为Fengycin A或Fengycin B的同系物或同分异构体。【结论】从N6-34菌株发酵液中分离获得了13种抗菌成分,为杨树溃疡病的生物防治提供了理论依据。 相似文献
6.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献7.
MORAIS PAULO AMORIM ANTÓNIO VIEIRA DA SILVA CLÁUDIA RIBEIRO TERESA COSTA SANTOS JORGE AFONSO COSTA HELOÍSA 《Journal of genetics》2015,94(3):509-512
Journal of Genetics - 相似文献
8.
链脲佐菌素诱导长爪沙鼠Ⅰ型糖尿病模型的实验研究 总被引:1,自引:0,他引:1
目的探讨链脲佐菌素(STZ)诱导长爪沙鼠Ⅰ型糖尿病模型的可能性,并观察模型动物早期肾脏损害情况。方法雄性长爪沙鼠96只,随机分为正常对照组(NC组)、模型组1(DM1组)、模型组2(DM2组),DM1及DM2组沙鼠分别一次性腹腔注射100 mg/kg、200 mg/kg STZ,NC组注射等量柠檬酸盐缓冲溶液。注射STZ后1、2、4、6周末,分别监测沙鼠一般情况,血糖、胰岛素等血清学指标和尿液指标,并处死沙鼠进行胰腺和肾脏组织的病理学检查。结果注射STZ 24 h后,DM2组及DM1组部分沙鼠逐渐出现典型的"三多一少"症状,随着病程的发展,DM2组沙鼠持续高血糖,DM1组沙鼠血糖值与NC组差异有显著性(P0.05),但有下降趋势;DM2组沙鼠胰岛素显著性降低(P0.05),其他血清学指标及尿液指标均显著性升高(P0.05),DM1组沙鼠各指标差异无显著性。DM2组沙鼠及DM1组少数沙鼠胰腺组织中可见胰岛β细胞减少、空泡样变性等变化,DM2组沙鼠肾脏组织中出现肾小球基质增多,毛细血管襻扩张等病变,DM1组沙鼠肾脏组织未见明显变化。结论 STZ 200 mg/kg可成功诱导长爪沙鼠Ⅰ型糖尿病模型,在病程早期沙鼠肾脏结构和功能已经发生改变。 相似文献
9.
人TRAIL基因cDNA的克隆及其在COS—7细胞中的表达 总被引:1,自引:0,他引:1
TRAIL(TNFrelatedapoptosisinducingligand)是最近克隆的肿瘤坏死因子(TNF)家族的新成员,由于它的蛋白质结构和生物学效应类似于FAS/APO1L,因此,也被称为APO2L。在低浓度下,TRAIL能迅速地诱导多种肿瘤细胞系的?.. 相似文献
10.
Basolateral plasma membrane localization of ouabain-sensitive sodium transport sites in the secretory epithelium of the avian salt gland 下载免费PDF全文
The distribution of Na+ pump sites (Na+-K+-ATPase) in the secretory epithelium of the avian salt gland was demonstrated by freeze-dry autoradiographic analysis of [(3)H] ouabain binding sites. Kinetic studies indicated that near saturation of tissue binding sites occurred when slices of salt glands from salt-stressed ducks were exposed to 2.2 μM ouabain (containing 5 μCi/ml [(3)H]ouabain) for 90 min. Washing with label-free Ringer's solution for 90 min extracted only 10% of the inhibitor, an amount which corresponded to ouabain present in the tissue spaces labeled by [(14)C]insulin. Increasing the KCl concentration of the incubation medium reduced the rate of ouabain binding but not the maximal amount bound. In contrast to the low level of ouabain binding to salt glands of ducks maintained on a freshwater regimen, exposure to a salt water diet led to a more than threefold increase in binding within 9-11 days. This increase paralleled the similar increment in Na+-K+-ATPase activity described previously. [(3)H]ouabain binding sites were localized autoradiographically to the folded basolateral plasma membrane of the principal secretory cells. The luminal surfaces of these cells were unlabeled. Mitotically active peripheral cells were also unlabeled. The cell-specific pattern of [(3)H]ouabain binding to principal secretory cells and the membrane-specific localization of binding sites to the nonluminal surfaces of these cells were identical to the distribution of Na+-K+-ATPase as reflected by the cytochemical localization of ouabain-sensitive and K+-dependent nitrophenyl phosphatase activity. The relationship between the nonluminal localization of Na+-K+-ATPase and the possible role of the enzyme n NaCl secretion is considered in the light of physiological data on electrolyte transport in salt glands and other secretory epithelia. 相似文献