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101.
Christine Heberden Thierry Mercier Isabelle Gaillard-Sanchez Brigitte Huet Paule Martel 《Experimental cell research》1995,218(2)
We assessed the presence and the role of membrane TGF-α in two rat liver epithelial cell lines, either parental or transfected with c-fos proto-oncogene. c-fos overexpressing cells had more TGF-α-like activity in their membranes. When TGF-α was removed by elastase or neutralized, the growth rates of both cell lines were markedly reduced, but to a higher extent for parental cells. If membrane TGF-α seemed to play a key contribution in normal cell growth, both cell lines were unable to react to the addition of soluble TGF-α, showing that these two forms of growth factors are not equivalent. 相似文献
102.
103.
Sabine Castano Bernard Desbat Isabelle Cornut Philippe Méléard Jean Dufourcq 《Letters in Peptide Science》1997,4(4-6):195-200
De novo designed extremely simplified amphipathic basicLeuiLysj (i = 2j) peptides of 8, 9 and 15residues were synthesized to clarify the mechanism of action of naturalcytotoxic and hemolytic small proteins or peptides. They proved to havestrong hemolytic activity towards human erythrocytes which increases withpeptide length. These peptides are highly surface active and form stablepeptidic films at the air/water interface. The sensitive and efficient FTIRmodulated polarization technique (PMIRRAS) allows one to obtain in situstructural and orientational information about the peptides at theinterface. A transition of secondary structure is observed: the shorterpeptides (8 and 9 residues) adopt -sheet structures while the longerone (15 residues) is folded into an -helix. In both cases, the peptideslie with the axis parallel to the interface. Their insertion into adimyristoylphosphatidylcholine monolayer can be followed from the increasein the surface and/or pressure of the films. In the mixed films, thepeptides adopt the same structure and orientation as observed at theair/water interface. Therefore, among the same series of peptides, atransition from -sheet to -helix occurs when the length increases(roughly >10 aa), but despite this drastic change both types ofstructures result in strongly hemolytic peptides. 相似文献
104.
Positive role of macaque cytotoxic T lymphocytes during SIV infection: decrease of cellular viremia and increase of asymptomatic clinical period 总被引:1,自引:0,他引:1
105.
Nicolae Barbacar Stefan Hinnisdaels Isabelle Farbos Françoise Monéger ré Lardon Catherine Delichère Armand Mouras Ioan Negrutiu 《The Plant journal : for cell and molecular biology》1997,12(4):805-817
The dioecious white campion (Silene latifolia) has been chosen as a working model for sexual development. In this species, sexual dimorphism is achieved through two distinct developmental blocks: inhibition of carpel development in male flowers, and early arrest of anther differentiation in female flowers. The combined advantages of the dioecious system and the availability of a sexual mutant lacking both male and female reproductive organs have been exploited in a molecular subtraction approach using male and asexual flower buds. This resulted in the cloning of 22 cDNA clones expressed in stamens at distinct stages of development. Fourteen of these clones corresponded to genes whose expression was detected in pre-meiotic stamens, a stage of development for which very little information is presently available. Furthermore, the absence of similarities with database sequences for ten clones suggests that they represent novel genes. Functional analysis of each clone will enable their positioning within the reproductive organ developmental pathway(s). In parallel, these clones are being exploited as developmental markers of early differentiation within the flower. 相似文献
106.
Mapping of a Gene for Long QT Syndrome to Chromosome 4q25-27 总被引:21,自引:0,他引:21
Jean-Jacques Schott Flavien Charpentier Sophie Peltier Patrick Foley Emmanuel Drouin Jean-Brieuc Bouhour Patricia Donnelly Gilles Vergnaud Lucien Bachner Jean-Paul Moisan Herv Le Marec Olivier Pascal 《American journal of human genetics》1995,57(5):1114-1122
Long QT syndrome (LQTS) is a heterogeneous inherited disorder causing syncope and sudden death from ventricular arrhythmias. A first locus for this disorder was mapped to chromosome 11p15.5. However, locus heterogeneity has been demonstrated in several families, and two other loci have recently been located on chromosomes 7q35-36 and 3p21-24. We used linkage analysis to map the locus in a 65-member family in which LQTS was associated with more marked sinus bradycardia than usual, leading to sinus node dysfunction. Linkage to chromosome 11p15.5, 7q35-36, or 3p21-24 was excluded. Positive linkage was obtained for markers located on chromosome 4q25-27. A maximal LOD score of 7.05 was found for marker D4S402. The identification of a fourth locus for LQTS confirms its genetic heterogeneity. Locus 4q25-27 is associated with a peculiar phenotype within the LQTS entity. 相似文献
107.
Esterase zymograms were obtained following polyacrylamide slab gel electrophoresis of protein extractsFusarium sambucinum and related species originating from different geographic locations and different matrices. The sites of esterase activity were recorded, and the Rfs were calculated. The data were used for the construction of phenograms by cluster analysis and nonlinear mapping by computerized classification techniques. The fifteen isolates ofF. sambucinum, the eight isolates ofF. torulosum and the six isolates ofF. spec. nov. each had identical profiles, and are therefore electrophoretically distinct species. The isolates ofF. sarcochroum, one ofF. sambucinum sensu lato (BBA 64280) and fifteen isolates ofF. sambucinum were electrophoretically indistinguishable from each other. We assume they are synonymous. The isolate ofF. bactridioides, one ofF. sambucinum sensu lato (BBA 64993) and eight isolates ofF. torulosum had uniform EST patterns, therefore the two species are electrophoretically identical. We assume they are also synonymous. The remaining three isolates ofF. sambucinum sensu lato are somewhat closely related toF. sambucinum isolates on the basis of our investigations. 相似文献
108.
A methodology for the pharmacodynamical assay of mixtures of 2 spasmogenic peptides is described, illustrated and discussed, with reference to a method intended for the chemists (P. Job, 1927). This allows a quick appreciation of the existence of synergism, of its own order of magnitude and of that of the doses for which it is significant. Also given is a fast way of curve-fitting the dose response to individual peptides, according to Clark's approximation. 相似文献
109.
110.
Jean-Jacques Madjar Monique Arpin Monique Buisson Jean-Paul Reboud 《Molecular & general genetics : MGG》1979,171(2):121-134
Summary Separation of the proteins from rat liver 40S and 60S ribosomal subunits and polysomes was done in four different two-dimensional polyacrylamide gel electrophoresis systems. The first dimension was run at acidic or basic pH, the second dimension either with sodium dodecyl sulphate or at acidic pH in 18% acrylamide. The position of each individual protein of both subunits and polysomes was determined in each system. This identification resulted from a new method avoiding any previous purification of individual proteins. The new proposed uniform nomenclature for mammalian ribosomal proteins (McConkey et al. in press) was used for numbering the proteins in the four systems. 相似文献