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71.
72.
Coxsackie A9 virus was identified by the authors during the fall of 1965 in Montreal in six children with fever and exanthem. Three of the six children were siblings. The exanthem was centrally distributed as described by Lerner et al. and consisted of discrete maculopapules 3 to 4 mm. in diameter. The viral agent was recovered and identified in tissue culture in five cases, while in the sixth Coxsackie type-A lesions were produced in suckling mice. Serological confirmation was obtained in two patients from whom sera were available. In contrast, no exanthem was observed in three older patients with a diagnosis of aseptic meningitis associated with Coxsackie A9 virus. In only one of 16 patients with Coxsackie B virus infection was an exanthem observed during the same period.The true incidence of Coxsackie A9-associated exanthems is difficult to determine because of the benign nature of the disease. 相似文献
73.
A study of 10 infants in severe metabolic acidemia (pH below 7) led to the conclusion that the clinical signs—hyperventilation, coma or lethargy, peripheral vascular collapse, a significantly palpable liver, and abdominal distension—may all be directly related to the metabolic acidemia. In five of 10 infants, an initial erroneous diagnosis of congestive heart failure or pneumonia was made. Dramatic clinical improvement followed correction of the acidemia with rapid intravenous administration of sodium bicarbonate. This rapid administration of sodium bicarbonate was safe, provided hypocalcemia was recognized and treated in its early stages. In severe metabolic acidemia the measurement of blood bicarbonate alone does not reflect adequately the magnitude of the acid-base derangement and repeated measurements of hydrogen ion concentration, Pco2 and bicarbonates are needed to evaluate and treat such infants correctly. 相似文献
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76.
Pierre Broquet Hélèna Baubichon-Cortay Pascal George Marie-Jo Peschard Pierre Louisot 《Journal of neurochemistry》1990,54(2):388-394
The tricyclic antidepressant desipramine, when added to culture medium, gave rise in C6 rat glioma cells to a decrease of the activity of the enzyme asialofetuin sialyltransferase. The inhibition was dose and time dependent and was observed in both multiplying cells and cells blocked with 2 mM thymidine or depletion of amino acids. This inhibition was rather specific to the sialyltransferase, as under the conditions where this enzyme was inhibited up to 70%, other enzymes such as dolichol phosphate mannose synthetase, glutamine synthetase, and glycerol phosphate dehydrogenase remained unaffected. This inhibition was not reversed after removal of desipramine from the medium and was not observed by direct addition of desipramine to the sialyltransferase incubation assay. Under the same conditions, W-7 [N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide], which is known to be a potent calmodulin antagonist and an inhibitor of calmodulin-dependent kinases, gave the same concentration-dependent inhibition profile of sialyltransferase as desipramine, whereas H-7 [1-(5-isoquinolinylsulfonyl)-2-methylpiperazine], which is an inhibitor of protein kinase C and cyclic nucleotide-dependent kinases, had no effect. So, it is suggested that desipramine inhibits the sialyltransferase activity in C6 glioma cells through a calmodulin-dependent system. 相似文献
77.
Robert L. Uffen Annette Colbeau Pierre Richaud Paulette M. Vignais 《Molecular & general genetics : MGG》1990,221(1):49-58
Summary
Rhodocyclus gelatinosus grew photosynthetically in the light and consumed H2 at a rate of about 665 nmol/min per mg protein. The uptake-hydrogenase (H2ase) was found to be membrane bound and insensitive to inhibition by CO. The structural genes of R. gelatinosus uptake-H2ase were isolated from a 40 kb cosmid gene library of R. gelatinosus DNA by hybridization with the structural genes of uptake-H2ase of Bradyrhizobium japonicum and Rhodobacter capsulatus. The R. gelatinosus genes were localized on two overlapping DNA restriction fragments subcloned into pUC18. Two open reading frames (ORF1 and ORF2) were observed. ORF1 contained 1080 nucleotides and encoded a 39.4 kDa protein. ORF2 had 1854 nucleotides and encoded a 68.5 kDa protein. Amino acid sequence analysis suggested that ORF1 and ORF2 corresponded to the small (HupS) and large (HupL) subunits, respectively, of R. gelatinosus uptake-H2ase. ORF1 was approximately 80% homologous with the small, and ORF2 was maximally 68% homologous with the large subunit of typical membrane-bound uptake-H2ases. 相似文献
78.
J.Michael Conlon Nicolas Chartrel Jerome Leprince Charles Suaudeau Jean Costentin Hubert Vaudry 《Peptides》1996,17(8):1291-1296
A peptide derived from the posttranslational processing of proenkephalin A was isolated from an extract of the brain of the European green frog Rana ridibunda and its primary structure established as: Tyr-Gly-Gly-Phe-Met-Arg-Arg-Val-Gly-Arg10-Pro-Glu-Trp-Trp-Gln-Asp-Tyr-Gln-Lys-Arg20-Tyr-Gly-Gly-Phe-Met. The structure was confirmed by chemical synthesis. The peptide represents an amphibian equivalent of bovine adrenal peptide E [preproenkephalin A (206–230)-peptide] but the sequence contains two amino acid substitutions (Met15 → Gln and Leu25 → Met) compared with the mammalian peptide. The data support previous hypotheses that the Leu-enkephalin sequence is not present in preproenkephalin A of amphibians. Intracerebroventricular injections of frog peptide E (10 and 100 ng) in mice had no significant effect on horizontal locomotor activity. The peptide, in doses up to 1 μg, had no effect on latency of escape jumping in the hot plate test and the peptide (100 ng) did not modify responses (paw licking, rearing, and escape jumping) in morphine-treated mice. 相似文献
79.
Spores of Aspergillus niger obtained by solid state fermentation on buckwheat seeds produced gluconic acid from glucose with a high yield, near 1.06 g gluconic acid/g glucose, close to the stoichiometric value. The reaction itself could be carried out either with purified biocatalyst or with the whole buckwheat medium resulting from spore production process. 200 g gluconic acid/L were obtained in 200 h with sequential feedings of glucose up to 190 g/L. 相似文献
80.