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101.
R. F. Maes A. Vieira I. Gomes P. Auge de Mello C. Bernal Lopez K. Costa Freitas 《Archives of virology》1977,55(4):275-285
Summary The effect of various polycations on the immune response potentiated with poly I:C was studied. It was found that low molecular weight polycations had no potentiating effect. Polylysine was ineffective whereas protamine was superior to lysozyme, poly-arginine, poly-histidine, DEAE-Dextran and histone.A foot-and-mouth disease trivalent vaccine composed of strains A24 Cruzeiro, O1 Caseros and C2 Resende elicited no immune response in swine when adjuvanted with aluminium hydroxide but was effective when emulsified in oil. In general, the immune response was potentiated ten-fold when the emulsion contained poly I:C. The antibody production was in most cases further potentiated by a factor of ten when the nucleic acid double-strand was complexed with 1:10 (w/w) DEAE-Dextran. Protamine was as effective, or perhaps even more, than DEAE-Dextran to this effect.Guinea pigs vaccinated with a water-in-oil emulsion type monovalent C3 vaccine showed an increase in antibody production when the vaccine contained poly I:C or poly I:C complexed with 1:10 (w/w) protamine.With 4 Figures 相似文献
102.
Rigor and resistance to stretch in vertebrate smooth muscle 总被引:2,自引:0,他引:2
103.
104.
The nonstructural proteins of Sindbis virus as studied with an antibody specific for the C terminus of the nonstructural readthrough polyprotein 总被引:7,自引:0,他引:7
A dodecapeptide containing the sequence of the C terminus of the nonstructural polyprotein of Sindbis virus has been synthesized and used to immunize rabbits. The antisera obtained precipitated polypeptides from cells infected with the HR strains of Sindbis or with temperature-sensitive mutants ts11 or ts18. Four different polypeptides, having apparent molecular weights of approximately 250,000, 220,000, 155,000, and 72,000, were immunoprecipitated by the antipeptide antiserum. The largest of these polypeptides is sufficiently large to represent a polyprotein translated from the entire nonstructural region of the genome. These data suggest that nsP4 of molecular weight 72,000 is produced by translation of the entire nonstructural region of the genome, which requires readthrough of an opal termination codon immediately upstream of nsP4, followed by post-translational cleavage of this polyprotein. The amounts of nsP4 and its precursors found in infected cells are small relative to the amounts of other nonstructural proteins present, as would be expected if readthrough of a termination codon is required. In addition, the relative amounts of nsP4 and of its precursors differ in HR-infected or ts mutant-infected cells and differ with temperature of infection, suggesting that temperature of infection or ts lesions affect translation and processing of the precursor polyprotein. 相似文献
105.
M Lopez de Ceballos E Guisado P Sanchez-Blazquez J Garzon J Del Rio 《Neuroscience letters》1983,39(2):217-222
Rats isolated at the time of calcification of the incisors show, after 14-18 months of social deprivation, an increased number of alpha 1-adrenoceptors labeled with [3H]WB 4101, both in the striatum and in the vas deferens, as well as a decreased number of alpha 2-adrenoceptors labeled with [3H]-clonidine in the vas deferens. Social isolation does not, however, modify the density of [3H]clonidine binding sites in the cerebral cortex. The functional state of alpha-adrenoreceptors in the vas deferens from isolated rats appears to correlate with the binding studies since the isolated tissue is hypersensitive to the contractile effect of exogenous noradrenaline and subsensitive to the inhibitory effect of clonidine on the electrically stimulated preparation. 相似文献
106.
107.
Billette J; Janse MJ; van Capelle FJ; Anderson RH; Touboul P; Durrer D 《The American journal of physiology》1976,231(4):1129-1139
108.
Developmental foundations of externalizing problems in young children: the role of effortful control 总被引:4,自引:0,他引:4
Examined associations between effortful control temperament and externalizing problems in 220 3-year-old boys and girls, controlling for co-occurring cognitive and social risk factors. We also considered possible additive and/or interactive contributions of child dispositional anger and psychosocial adversity, and whether relations between effortful control and early externalizing problems were moderated by child gender. Individual differences in children's effortful control abilities, assessed using behavioral and parent rating measures, were negatively associated with child externalizing problems reported by mothers, fathers, and preschool teachers. These associations were not overshadowed by other cognitive or social risk factors, or by other relevant child temperament traits such as proneness to irritability. Further analyses revealed that associations between externalizing problem behavior and effortful control were specific to components of child problem behavior indexing impulsive-inattentive symptoms. Thus, children's effortful control skills were important correlates of children's early disruptive behavior, a finding that may provide insight into the developmental origins of chronic behavioral maladjustment. 相似文献
109.
110.