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排序方式: 共有597条查询结果,搜索用时 15 毫秒
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P Dejours J Armand H Beekenkamp 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1992,315(4):145-150
The pH, the osmolality and the urea and ammonia concentrations in blood, as well as the net urea and ammonia excretions, were studied in the amphibian Xenopus laevis exposed for several weeks to increased osmotic pressure (OP) of the ambient water, as a result of the addition of either NaCl or mannitol to the water. The pH and the ammonia concentration of the blood were independent of the variations of the ambient osmolarity. On the contrary, the blood osmolality and its urea concentration increased markedly when the ambient OP was augmented. The increase of ambient OP by NaCl addition to the medium augmented the urea net excretion and slightly decreased the ammonia excretion. When the increase of ambient OP resulted from the addition of mannitol in the water, excretions of urea and ammonia became negligible. 相似文献
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Didier Arseguel Armand Lattes Michel Baboul ne 《Biocatalysis and Biotransformation》1990,3(3):217-225
Horseradish peroxidase was chemically conjugated on its carbohydrate moieties with short aliphatic chains (C8 and C16). An analytical method using FT.IR spectroscopy was developed to analyze this alteration in enzyme structure. This method is non-destructive, and can be applied directly to samples of the reaction mixture. More general applications of this technique are described and discussed. 相似文献
6.
Dominique Dorin-Semblat Claudia Demarta-Gatsi Romain Hamelin Florence Armand Teresa Gil Carvalho Marc Moniatte Christian Doerig 《PloS one》2015,10(12)
Casein kinase 1 (CK1) is a pleiotropic protein kinase implicated in several fundamental processes of eukaryotic cell biology. Plasmodium falciparum encodes a single CK1 isoform, PfCK1, that is expressed at all stages of the parasite’s life cycle. We have previously shown that the pfck1 gene cannot be disrupted, but that the locus can be modified if no loss-of-function is incurred, suggesting an important role for this kinase in intra-erythrocytic asexual proliferation. Here, we report on the use of parasite lines expressing GFP- or His-tagged PfCK1 from the endogenous locus to investigate (i) the dynamics of PfCK1 localisation during the asexual cycle in red blood cells, and (ii) potential interactors of PfCK1, so as to gain insight into the involvement of the enzyme in specific cellular processes. Immunofluorescence analysis reveals a dynamic localisation of PfCK1, with evidence for a pool of the enzyme being directed to the membrane of the host erythrocyte in the early stages of infection, followed by a predominantly intra-parasite localisation in trophozoites and schizonts and association with micronemes in merozoites. Furthermore, we present strong evidence that a pool of enzymatically active PfCK1 is secreted into the culture supernatant, demonstrating that PfCK1 is an ectokinase. Our interactome experiments and ensuing kinase assays using recombinant PfCK1 to phosphorylate putative interactors in vitro suggest an involvement of PfCK1 in many cellular processes such as mRNA splicing, protein trafficking, ribosomal, and host cell invasion. 相似文献
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M L Hautekeete R F De Bock D R Van Bockstaele G C Colpin Z N Berneman M E Peetermans 《Blut》1987,55(5):447-452
Several authors have studied the T-lymphocyte subpopulations in B-cell chronic lymphocytic leukemia (B-CLL), but previous studies were performed after preceding enrichment procedures, which are known to cause selective losses of certain subpopulations. To correct for this deficiency we used flow cytometric analysis, which enabled us to measure subpopulations directly on total blood samples. We studied T-lymphocyte subsets with OKT monoclonal antibodies in 45 patients with B-CLL. Serum levels of IgG, IgA and IgM were assayed simultaneously and findings were correlated with clinical stage (Rai classification). The absolute number of CD4-positive cells decreased in more advanced Rai stages, while the absolute number of CD8-positive cells increased, resulting in a progressive reduction in CD4/8 ratio. Results from patients in stages with equal prognosis (Rai I and II, Rai III and IV) were similar and when these results were grouped the observed differences were highly significant and clearly correlated with all prognostic groups. 相似文献
8.
Sidney L. Vail Oliver D. Dailey Eugene J. Blanchard Armand B. Pepperman James L. Riopel 《Journal of Plant Growth Regulation》1990,9(1-3):77-83
Strigol and some of its synthetic precursors and analogs are known to be germination stimulants for broomrape (Orobanche ramosa) and witchweed (Striga asiatica). Fifteen synthetic terpenoids, similar in structure to one of the four rings of the strigol molecule, were evaluated in two bioassays as seed germination stimulants with broomrape, and nine were found to be active. Five of the more active compounds contained ester groups. Whereas the study was intended primarily to evaluate forced germination of broomrape by aqueous solutions, the results are almost qualitatively identical for broomrape and witchweed. Monocyclic compounds with chemical structures similar to two of the rings of strigol have now been shown to possess significant bioactivity as germination stimulants.Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable. 相似文献
9.
L Montagnier D Berneman D Guétard A Blanchard S Chamaret V Rame J Van Rietschoten K Mabrouk E Bahraoui 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1990,311(12):425-430
Antibodies prepared against a peptide corresponding to the site of cyto-adherence of Mycoplasma genitalium adhesine inhibit or reduce the infectivity of the HIV-1BRU and HIV-2ROD strains of Human Immunodeficiency Virus in lymphoid cells. These results strengthen the hypothesis that some mycoplasmas may play an important part in HIV replication and pathogenicity. 相似文献
10.
Judith M. Bradow William J. Connick Jr. Armand B. Pepperman 《Journal of Plant Growth Regulation》1988,7(4):227-239
Four synthetic multiring analogs of strigol, a naturally occurring sesquiterpene lactone that promotes germination of dormant seeds ofStriga (witchweed), were found to stimulate germination of dormantLactuca (lettuce) seeds. The effects on light-sensitive and light-insensitive lettuce seeds were concentration-dependent and exceeded those produced by equimolar (0.1 mM) solutions of gibberellic acid. Strigol and epistrigol promoted lettuce seed germination to a lesser degree than did the synthetic analogs. The strigol group compounds had minimal effect on the germination of monocot seeds. The results indicate that the synthetic strigol analogs have plant growth regulatory activity in dormant seeds of genera beyondStriga in which germination stimulation by strigol and the synthetic analogs was first demonstrated.Names of companies of commercial products are given solely for the purpose of providing specific information; their mention does not imply recommendation or endorsement by the U.S. Department of Agriculture over others not mentioned. 相似文献