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101.
Dominique Margelin Anny Fourtanier Thierry Thevenin Chantal Medaisko Monique Breton Jacques Picard 《Photochemistry and photobiology》1993,58(2):211-218
Abstract— The effect of UVB exposure on the distribution and synthesis of dermal proteoglycans was measured in the skin of hairless mice. Two groups of mice were included: one was irradiated for 10 weeks; the other was kept as control. After intraperitoneal injection of sodium 35 S-sulfate, punch biopsies were taken for histology and proteoglycans were extracted from the remaining skin with 4 M guanidinium chloride, containing 3–[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (0.5%, weight per volume). Following proteolytic digestion, the glycosaminoglycan constituents were isolated and analyzed by quantitative cellulose acetate electrophoresis and enzymatic digestibility.
Under the influence of UVB radiation, newly synthesized proteoglycans measured by35 SO4 uptake increased as much as 60%. In addition, the irradiated skin had a higher average content of proteoglycan than had control skin (4981 μg vs 4134 μg/g dry weight). This could be ascribed to an increase in heparin (1400 vs 533 μ g/g dry weight) and heparan sulfate (472 vs 367 μg/g dry weight), whereas no change in the concentration of hyaluronic acid (1243 vs 1372 μg/g dry weight) and dermatan sulfate (1866 vs 1863 μg/g dry weight) was observed. The irradiated animals also exhibited a marked increase in the synthesis of heparan sulfate and heparin (62% and 71%, respectively). These results demonstrate that chronic doses of UVB altered proteoglycan metabolism through both quantitative and qualitative changes. 相似文献
Under the influence of UVB radiation, newly synthesized proteoglycans measured by
102.
103.
Ren Traber Hans Hofmann Hans-Rudolf Loosli Monique Ponelle Albert von Wartburg 《Helvetica chimica acta》1987,70(1):13-36
Novel Cyclosporins from Tolypocladium inflatum. The Cyclosporins K–Z The fungus T. inflatum produces a plethora of oligopeptides, the cyclosporins, which exhibit remarkable biological activities. Cyclosporin A, the main metabolite, represents a potent immunosuppressant which opened new ways in the immunotherapy of bone marrow and organ transplantations. In addition to the already described cyclosporins A–I, we report now the isolation of the cyclosporins K–Z. The structural assignments of these novel congeners are based on chemical degradation, correlation reactions, mass spectra, and extensive analysis of 1H- and 13C-NMR spectra. All cyclosporins are cyclic undecapeptides differing from each other by minor variations in the amino-acid sequence. Comparison of the immunosuppressive and antifungal effects furnished new information concerning structure-activity relationships. 相似文献
104.
Alexandre Delye de Clauzade de Mazieux Michel Marot Monique Becker 《Comptes Rendus Mecanique》2006,334(11):669-673
d-dominating sets in graphs are very important in system and network engineering. Their constructions is thus an important research topic. An heuristic which forms such sets by using a given criterion is proposed. We simplify the heuristic presented elsewhere. We extend it and prove the correctness of the extended heuristic. This heuristic has the advantage of being distributed and scalable. To cite this article: A. Delye de Clauzade de Mazieux et al., C. R. Mecanique 334 (2006). 相似文献
105.
We consider a quantum system of non-interacting fermions at temperature T, in the framework of linear response theory. We show that semiclassical theory is an appropriate framework to describe some of their thermodynamic properties, in particular through asymptotic expansions in ? (Planck constant) of the dynamical susceptibilities. We show how the closed orbits of the classical motion in phase space manifest themselves in these expansions, in the regime where T is of the order of ?. 相似文献
106.
107.
(±) Sarkomycin ethyl ester has been prepared in four steps from ethyl acrylate. 相似文献
108.
Jacques Dubac Pierre Mazerolles Monique Joly 《Journal of organometallic chemistry》1977,128(2):C18-C20
Stereospecific synthesis of geometric isomers of 1,2-dimethyl-1-phenylsilacyclopentane is described. We demonstrate that brominolysis of the arylsilicon bond occurs with predominant inversion of configuration at the silicon atom of the silacyclopentane ring. 相似文献
109.
Jacques Dubac Pierre Mazerolles Monique Joly 《Journal of organometallic chemistry》1977,128(2):C21-C24
The stereoselective alcoholysis of 1,2-dimethyl-1-chlorosilacyclopentane and the catalytic alcoholysis of 1,2-dimethylsilacyclopentane are described. 相似文献
110.
Jean Pierre Majoral Monique Revel Raymond Kraemer Hlne Germa Jacques Navech 《Journal of heterocyclic chemistry》1977,14(5):749-755
The reaction of phosphodi- or trihydrazides with orthoesters affords mainly 2,3,4,5-tetrahydro-1,2,4,5,3-tetrazaphosphorines and sometimes 4-amino-1,2,4,3-triazaphospholidines. These 1,2,4,5,3-tetrazaphosphorines present a prototropy which explains different pathways of the reaction of these derivatives with formaldehyde or acetone, The structure of all heterocycles which were obtained was established by nmr spectra. 相似文献