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排序方式: 共有300条查询结果,搜索用时 171 毫秒
1.
Summary Direct gene analysis of the haptoglobin gene region was carried out by Southern blotting using an Hp cDNA as probe. Two types of polymorphism were observed: one due to intragenic duplication, is characterized by a constant fragment length difference of 1700bp observed with several enzymes and by complete correspondence with the protein molecular weight polymorphism; the second type, due to point mutation, was represented by two additional restriction sites for Eco RI and Pst I, with a frequency comparable to that of other genes. These two mutations segregated together in families, suggesting that the recently described Hp related gene is closely linked to the Hp gene. Moreover, they were completely associated with each other. The evolutionary significance of this finding is discussed. 相似文献
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Salvatore Oliviero Mario DeMarchi Angelo O. Carbonara Luigi F. Bernini Giuliano Bensi Giovanni Raugei 《Human genetics》1985,71(1):49-52
Summary The protein and gene structure of the Hp Johnson variant (Hp3) were analyzed in two related heterozygous individuals. The molecular weight (23kd) and amino acid composition of Hp3 alpha chain were in agreement with the triplicated structure first suggested by Smithies in 1964. Direct gene analysis by Southern blotting showed a three-fold tandem repeat of the same 1.7 kb DNA segment implicated in the Hp2 gene duplication. On the basis of these data a nine exon model for the Hp3 gene is proposed. 相似文献
4.
Selenium,zinc, and thyroid hormones in healthy subjects 总被引:3,自引:0,他引:3
Oliviero Olivieri Domenico Girelli Anna Maria Stanzial Luigi Rossi Antonella Bassi Roberto Corrocher 《Biological trace element research》1996,51(1):31-41
Iodothyronine 5′ deiodinase, which is mainly responsible for peripheral T3 production, has recently been demonstrated to be a selenium (Se)-containing enzyme. The structure of nuclear thyroid hormone
receptors contains Zinc (Zn) ions, crucial for the functional properties of the protein. In the elderly, reduced peripheral
conversion of T4 to T3 with a lower T3/T4 ratio and overt hypothyroidism are frequently observed. We measured serum Se and RBC GSH-Px (as indices of Se status), circulating
and RBC Zinc (as indices of Zn status), thyroid hormones and TSH in 109 healthy euthyroid subjects (52 women, 57 men), carefully
selected to avoid abnormally low thyroid hormone levels induced by acute or chronic diseases or calorie restriction. The subjects
were subdivided into three age groups. To avoid under- or malnutrition conditions, dietary records were obtained for a sample
of 24 subjects, randomly selected and representative of the whole population for age and sex. Low T3/T4 ratios and reduced Se and RBC GSH-Px activity were observed only in the older group. A highly significant linear correlation
between the T3/T4 ratio and indices of Se status was observed in the older group of subjects (r=0.54;p<0.002, for Se;r=0.50;p<0.002, for RBC GSH-Px). Indices of Zn status did not correlate with thyroid hormones, but RBC Zn was decreased in older as
compared with younger subjects. We concluded that reduced peripheral T4 conversion is related to impaired Se status in the elderly. 相似文献
5.
Alessandro Pellegrineschi Oliviero Davolio-Mariani 《Plant Cell, Tissue and Organ Culture》1996,47(1):79-86
A method is described for producing genetically transformed plants from explants of three scentedPelargonium spp. Transgenic hairy root lines were developed fromPelargonium spp leaf explants and microcuttings after inoculation withAgrobacterium rhizogenes strains derived from the agropine A4 strain. Hairy root lines grew prolifically on growth regulator-free medium. Transgenic shoots were regenerated from hairy roots and the plants have been successfully transferred to soil. The phenotype of regenerated plants has been characterized as having abundant root development, more leaves and internodes than the controls, short internodes and highly branched roots and aerial parts. Southern blot analyses have confirmed the transgenic nature of these plants. 相似文献
6.
Cloning, characterization, and modeling of a monoclonal anti-human transferrin antibody that competes with the transferrin receptor. 下载免费PDF全文
M. Orlandini A. Santucci A. Tramontano P. Neri S. Oliviero 《Protein science : a publication of the Protein Society》1994,3(9):1476-1484
In this report we describe the isolation and characterization of a monoclonal antibody against human serum transferrin (Tf) and the cloning and sequencing of its cDNA. The antibody competes with the transferrin receptor (TR) for binding to human Tf and is therefore expected to bind at or very close to a region of interaction between Tf and its receptor. From the deduced amino acid sequence, we constructed a 3-dimensional model of the variable domains of the antibody based on the canonical structure model for the hypervariable loops. The proposed structure of the antibody is a first step toward a more detailed characterization of the antibody-Tf complex and possibly toward a better understanding of the Tf interaction with its receptor. The model might prove useful in guiding site-directed mutagenesis studies, simplifying the experimental elucidation of the antibody structure, and in the use of automatic procedures to dock the interacting molecules as soon as structural information about the structure of the human Tf molecule will be available. 相似文献
7.
Manuela Aragno Elena Tamagno Giuseppe Poli Giuseppe Boccuzzi Enrico Brignardello Oliviero Danni 《Free radical research》1994,21(6):427-435
Dehydroepiandrosterone (DHEA), a lipid soluble steroid, administered to rats (100 mg/kg b.wt) by a single intraperitoneal injection, increases to twice its normal level in the liver microsomes. Microsomes so enriched become resistant to lipid peroxidation induced by incubation with carbon tetrachloride in the presence of a NADPH-regenerating system: also the lipid peroxidation-dependent inactivation of glucose-6-phosphatase and gamma-glutamyl transpetidase due to the haloalkane are prevented. Noteworthy, the liver microsomal drug-metabolizing enzymes and in particular the catalytic activity of cytochrome P450IIE1, responsible for the CCl4-activation, are not impaired by the supplementation with the steroid. Consistently, in DHEA-pretreated microsomes the protein covalent binding of the trichloromethyl radical (CCl3°), is similar to that of not supplemented microsomes treated with CCl4. It thus seems likely that DHEA protects liver microsomes from oxidative damage induced by carbon tetrachloride through its own antioxidant properties rather than inhibiting the metabolism of the toxin. 相似文献
8.
Xiao Wang Haiyun Xie Yufan Ying Danni Chen Jiangfeng Li 《Journal of cellular and molecular medicine》2020,24(18):10302-10310
Epigenetics has long been a hot topic in the field of scientific research. The scope of epigenetics usually includes chromatin remodelling, DNA methylation, histone modifications, non‐coding RNAs and RNA modifications. In recent years, RNA modifications have emerged as important regulators in a variety of physiological processes and in disease progression, especially in human cancers. Among the various RNA modifications, m6A is the most common. The function of m6A modifications is mainly regulated by 3 types of proteins: m6A methyltransferases (writers), m6A demethylases (erasers) and m6A‐binding proteins (readers). In this review, we focus on RNA m6A modification and its relationship with urological cancers, particularly focusing on its roles and potential clinical applications. 相似文献
9.
Wang Lingfeng Guo Ying Ye Jiayi Pan Zeyue Hu Peihao Zhong Xiaoming Qiu Fengmei Zhang Danni Huang Zhen 《Neurochemical research》2021,46(7):1869-1880
Neurochemical Research - Piceatannol is a natural plant-derived compound with protective effects against cardiovascular diseases. However, its effect on cerebral ischaemia–reperfusion injury... 相似文献
10.
ODB基因在植物同源重组依赖性的DNA双键断裂修复过程中起重要作用,对植物诱变育种具有潜在的应用价值。克隆烟草NtODB基因并分析其表达特征为丰富ODB基因在同源重组DNA修复过程中的作用提供证据。为得到烟草NtODB基因序列,采用电子克隆技术获得该基因cDNA序列并克隆验证。进一步使用生物信息学方法分析该基因表达特征,对预测蛋白的理化性质、信号肽、高级结构等进行预测。生物信息学分析结果表明,NtODB基因开放阅读框包含579个碱基,蛋白含192个氨基酸残基,NtODB蛋白具有碱性和亲水性,主要定位于细胞质内;实时荧光定量PCR检测结果显示NtODB基因在不同组织中呈现组成型表达特征;亚细胞定位检测提示NtODB主要表达于细胞膜和叶绿体。NtODB基因的克隆与表达分析及其蛋白高级结构和理化性质的预测,可为进一步丰富ODB基因在同源重组依赖的DNA修复系统中的作用机制提供证据。 相似文献