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In this study we have investigated the immune humoral response in the associated vaccination with smallpox, tetanus and typhoid fractionated vaccine (trivaccine) administered in two series at 1 month interval, by dermojet, in a group of young people of 18-20 years old. The results were comparatively estimated with those obtained in two groups of young people of the same age (control group), separately immunized with two components of the tri-vaccine: fractionated smallpox vaccine and tetanus toxoid, following-up the humoral response to the two vaccine components. It was find that, at the end of the surveillance period, similar results were obtained for the testing group and control group, the antibody titers (in geometric mean) presenting very close values: 1/1,140,463 for the testing group, and 1/1,053,583 for the control group against vaccinia component, and 1/1,86,880,586 for the testing group and 1/79,900,431 for the control group, against the tetanus component. The results obtained entitle us to propose this vaccination scheme for the vaccination practice.  相似文献   
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A lyophilized, heat-killed, phenol preserved typhoid vaccine (5 x 10(8) cells) suspended in 0.1 ml unadsorbed concentrated tetanus vaccine (10 Lf) was administered in man by intradermal route. This association of the two vaccines resulted in milder postvaccinal reactions: moreover, the immunological properties of typhoid vaccine, as certified by the passive protection test of the mouse with sera of the vaccines and the H and O agglutinin titres found in these immune sera, were perfectly conserved. Consequently, the mixed typhoid-tetanus vaccination in man by intradermal route is possible and advantageous for practical and economical reasons.  相似文献   
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Summary A pea vicilin promoter-diphtheria toxin A (DTx-A) chain gene fusion was introduced into Arabidopsis and tobacco. The chimeric Dtx-A gene behaves as a dominant, seed-lethal, Mendelian factor, and the segregation ratios are consistent with the numbers of integrated copies as revealed by Southern blotting. Germination deficiency results from distinct developmental abnormalities, thus allowing genetic dissection of seed development. The endosperm is affected first in both species. In Arabidopsis, full cellularization of the initially syncytial endosperm does not take place, which results in shrinkage and a shriveled appearance of the mature dry seed. The embryo, which appears structurally normal and lacks visible lesions, ceases to develop at the partially recurved cotyledon stage and does not use the remaining endosperm. In tobacco, peripheral degeneration and premature termination of cellular endosperm development occurs at the cotyledon initiation stage. Lesions appear in the cotyledons at the advanced cotyledon stage, but the embryo continues to grow and attains nearly the same size and level of differentiation as mature wild-type embryos before degeneration and intracellular disintegration take place throughout. Accumulation of protein bodies and other cytoplasmic inclusions is very limited and occurs only in few cells. The timing and distribution of lesions follow a pattern typical for accumulation of protein bodies in wild-type seeds. These observations are consistent with expression of the vicilin promoter in the enlargement phase of cell differentiation. A novel tissue interaction arises, when the embryo uses up all the arrested endosperm: the embryo proves to be capable of absorbing the parenchyma layers of the integument, which are normally obliterated by, and incorporated into, the endosperm. The mature seed thus consists of a seed coat of one rigid cell layer, and a degenerated embryo. The genetic ablation technique has thus contributed to the establishment of the sequence of events and elucidation of the role of different cell lineages and tissues in seed development.  相似文献   
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Using a battery of seven lectin-ferritin conjugates as probes for cell surface glycoconjugates, we have studied the pattern of plasmalemmal differentiation of cells in the embryonic rat pancreas from day 15 in utero to the early postpartum stage. Our results indicate that differentiation of plasmalemmal glycoconjugates on acinar, endocrine, and centroacinar cells is temporally correlated with development and is unique for each cell type, as indicated by lectin-ferritin binding. Specifically, (a) expression of adult cell surface saccharide phenotype can be detected on presumptive acinar cells as early as 15 d in utero, as indicated by soybean agglutinin binding, and precedes development of intracellular organelles characteristic of mature acinar cells; (b) maturation of the plasmalemma of acinar cells is reached after intracellular cytodifferentiation is completed, as indicated by appearance of Con A and fucoselectin binding sites only at day 19 of development; conversely, maturation of the endocrine cell plasmalemma is accompanied by "loss" (masking) of ricinus communis II agglutinin receptors; and (c) binding sites for fucose lectins and for soybean agglutinin are absent on endocrine and centroacinar cells at all stages examined. We conclude that acinar, centroacinar, and endocrine cells develop from a common progenitor cell(s) whose plasmalemmal carbohydrate composition resembles most closely that of the adult centroacinar cell. Finally, appearance of acinar lumina beginning at approximately 17 d in utero is accompanied by differenetiation of apical and basolateral plasmalemmal domains of epithelial cells, as indicated by enhanced binding of several lectin-ferritin conjugates to the apical plasmalemmal, a pattern that persists from this stage through adult life.  相似文献   
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