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排序方式: 共有501条查询结果,搜索用时 15 毫秒
1.
Identification of regulatory elements within the minimal promoter region of the human endogenous ERV9 proviruses: accurate transcription initiation is controlled by an Inr-like element. 下载免费PDF全文
G La Mantia B Majello A Di Cristofano M Strazzullo G Minchiotti L Lania 《Nucleic acids research》1992,20(16):4129-4136
2.
Kay Huebner Teresa Druck Sal LaForgia Jerzy Lasota Carlo M. Croce Luisa Lanfrancone Emilio Donti Gina Pengue Girolama La Mantia Pier-Giuseppe Pelicci Luigi Lania 《Human genetics》1993,91(3):217-222
cDNA clones encoding zinc finger motifs were isolated by screening human placenta and T-cell (Peer) cDNA libraries with zinc finger (ZNF) consensus sequences. Unique cDNA clones were mapped in the human genome by rodent-human somatic cell hybrid analysis and in some cases in situ chromosomal hybridization. ZNF 80 mapped to 3p12-3qter, ZNF 7 was previously mapped to 8q24 and is here shown by in situ hybridization and use of appropriate hybrids to map telomeric to the MYC locus. ZNF 79 mapped to 9q34 centromeric to the ABL gene and between a constitutional chromosomal translocation on the centromeric side and the CML specific ABL translocation on the telomeric side. ZNF77 mapped to 19p while ZNF 78L1 (pT3) mapped to 19q. Chromosome 19 carries many ZNF loci and other genes with zinc finger encoding motifs; the pT3 clone additionally detected a locus designated ZNF 78L2, which mapped to chromosome region 1p, most likely in the region 1p32 where the MYCL and JUN loci map. 相似文献
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4.
Effect of Kainic Acid, Glutamate, and Aspartate on CO2 Production by Goldfish Tectal Slices 总被引:1,自引:1,他引:0
Paolo Migani Alessandro Poli Antonio Contestabile Rosanna Bissoli Giuliana Cristini Ottavio Barnabei 《Journal of neurochemistry》1982,39(4):970-975
For a study of the excitatory effect of kainate, glutamate, and aspartate in the goldfish optic tectum, these substances were tested on the production of CO2 from radioactive glucose in tectal slices incubated in Krebs-Ringer medium for fish. Kainate increased the rate of CO2 production for up to 30 min in a dose-related manner, the effect being maximum at 0.1 mM concentration and decreasing at higher doses. The effect was blocked by ouabain (1 mM) as well as by the substitution of choline for Na+ in the incubation medium. Glutamate and aspartate exerted a less pronounced excitatory effect on CO2 production at higher concentration than kainate. This effect was also abolished by ouabain. Glutamate, added to the medium at a concentration at least 100-fold higher than kainate, partially reversed the increase in CO2 production induced by kainic acid. No similar effect was noticed for aspartate. The supposed glutamate antagonists glutamic acid diethylester (1 mM) and proline (5 mM) did not affect the excitatory action of kainic acid or exert an antagonistic effect towards glutamate. At higher concentration (10 mM) glutamic acid diethylester increased CO2 production, an effect that was, however, ouabain insensitive. Methyltetrahydrofolic acid (1 mM), a substance reported to compete for the kainate receptor, did not inhibit the effect of kainic acid or increase CO2 production. 相似文献
5.
Dr. William L. Elkins Giuliana Pierson William Negendank Karen S. Zier 《Immunogenetics》1982,15(5):485-499
Lymphocytes from an extensively transfused patient with aplastic anemia were induced to cytotoxicity against target cells from several HLA-matched siblings by in vitro stimulation with allogeneic cells. Effective stimulating cells shared HLA-B7 with the patient, but not all B7 individuals were effective. An additional factor, which was found to segregate in both the patient's and an unrelated sibship, was also necessary. Segregation of this minor alloantigen, W, was also revealed among the patient's HLA-matched sibs by differential susceptibility to lysis by effectors from the patient. The ratio of six positive to four negative siblings suggests that the antigen difference might be coded by a single locus. Lymphocytes from a normal sib, who like the patient is lacking the minor antigen, could not be induced to cytotoxicity against positive targets. Thus in vivo sensitization of the donor of the responding cells appears to be necessary for the demonstration of the cytotoxic response to the minor antigen in vitro. No correlation was observed between the segregation pattern of W and of known blood group antigens, and no cytotoxic antibody to W was detected in the patient's serum in several trials.Abbreviations used in this paper MHC
major histocompatibility complex
- Tc
thymus dependent cells capable of mediating cytotoxicity in the absence of Immoral antibody
- GVHD
graft versus host disease
- CML
cell mediated lympholysis
- MLC
unidirectional mixed lymphocyte culture
- ADCC
antibody-dependent cell mediated cytotoxicity 相似文献
6.
Experimental and simulative dissociation of dimeric Cu,Zn superoxide dismutase doubly mutated at the intersubunit surface 下载免费PDF全文
Maragliano L Falconi M Sergi A Cioni P Castelli S Lania A Stroppolo ME Strambini G Ferrario M Desideri A 《Biophysical journal》2005,88(4):2875-2882
The equilibrium properties of dimeric Photobacterium leiognathi Cu,Zn superoxide dismutase mutant bearing two negative charges in the amino acid clusters at the association interface has been studied, experimentally and computationally, and compared to those of the native enzyme. Pressure-dependent dissociation is observed for the mutant, as observed by the fluorescence shift of the unique tryptophan residue located at the intersubunit surface. The spectral shift occurs slowly, reaching a plateau after 15-20 min, and is fully reversible. Measurement of the degree of dissociation allows us to calculate the standard volume variation upon association and the dissociation constant at atmospheric pressure. On the other hand the native protein is undissociable at any pressure. In the simulative approach, the dissociation free energy has been calculated through the blue moon calculation method for the case of a multidimensional reaction coordinate, corrected for the rotational contribution within the semiclassical approximation for a free rigid-body rotor. The scheme permits to define a definite path for the rupture of the dimer and to calculate the effective force involved in the process. The calculated free energy difference is close to the experimental one, and the value obtained for the mutant is well below that obtained for the native protein, indicating that the theoretical reaction scheme is able to reproduce the experimental trend. Moreover, we find that, when the separation distance increases, the protein structure of the monomer is stable in line with the fast recovery of the original fluorescence properties after decompression, which excludes the presence of partly unfolded intermediates during the dimer-monomer transition. 相似文献
7.
8.
A Galtieri G Natoli A Lania L Calabrese 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,83(3):555-559
A Cu,Zn superoxide dismutase was purified for the first time from an elasmobranch species (Prionace glauca) and showed the following differences with respect to other animal superoxide dismutases. The enzyme displays a low isoelectric point. The enzyme activity is unusually independent of ionic strength. The isolated enzyme has 30% of its copper in the reduced state. 相似文献
9.
García Cristina Ranieri Giuliana Rendueles Manuel Díaz Mario 《Bioprocess and biosystems engineering》2020,43(1):55-66
Bioprocess and Biosystems Engineering - Pseudomonas taetrolens constitutes an efficient platform for the biosynthesis of lactobionic acid, a potentially prebiotic compound. Unfortunately, an... 相似文献