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11.
Role of different lymphoid tissues in the initiation and maintenance of DNA-raised antibody responses to the influenza virus H1 glycoprotein.
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Antibody responses in mice immunized by a single gene gun inoculation of plasmid expressing the influenza virus H1 hemagglutinin and in mice immunized by a sublethal H1 influenza virus infection have been compared. Both immunizations raised long-lived serum responses that were associated with the localization of antibody-secreting cells (ASC) to the bone marrow. However, the kinetics of these responses were 4 to 8 weeks slower in the DNA-immunized than in the infection-primed mice. Following a gene gun booster, the presence of ASC in the inguinal lymph nodes, but not in other lymph nodes, revealed gene gun responses being initiated in the nodes that drain the skin target site. Both pre- and postchallenge, the DNA-immunized mice had 5- to 10-times-lower levels of antibody and ASC than the infection-primed mice. 相似文献
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PCR products were characterized by electrophoresis, blotting and hybridization. In addition to the bands of expected size, bands of slower electrophoretic mobility were often detected. The slower bands completely disappeared when the PCR products were subjected to slow cooling, treated with S1 nuclease or run on an alkaline gel, whereas the bands of expected size were unaffected. The slower bands are therefore likely to contain single-stranded DNA. 相似文献
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Globin synthesis on reticulocyte membrane-bound ribosomes 总被引:1,自引:0,他引:1
W R Woodward S D Adamson H M McQueen J W Larson S M Estvanik P Wilairat E Herbert 《The Journal of biological chemistry》1973,248(5):1556-1561
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The polypeptide composition of the large and small subunits of Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) from Arabidopsis thaliana, A. suecica and Cardaminopsis arenosa have been studied by IEF (isoelectric focusing) analysis. The putative recent alopolyploid origin of A. suecica is supported. The chloroplast encoded large subunits served to identify solely A. thaliana as the maternal parent whereas the nuclear encoded small subunits indicate C. arenosa as the paternal species. 相似文献
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Herbert Athenstaedt 《Cell and tissue research》1967,81(1):62-73
Zusammenfassung Bei menschlichem und tierischem Sehnengewebe wurde pyroelektrisches Verhalten festgestellt. Pyroelektrisches Verhalten bedeutet, daß eine permanente makroskopische elektrische Polarisation und somit ein permanentes elektrisches Moment in Richtung der pyroelektrischen Achse vorhanden ist.Die pyroelektrische (und daher auch piezoelektrische) Achse verläuft in der Längsrichtung der Sehnenfasern bzw. ihrer Kollagenfibrillen. Sie stimmt überein mit der optischen Faserachse, in deren Verlauf positiv einachsige Doppelbrechung bekannt ist. Sehnen mit leidlicher Parallelausrichtung ihrer Faserbündel zeigen dementsprechend makroskopisch eine pyroelektrische Achse parallel zur physiologischen Sehnenlängsachse. Bei seilartiger Bündelung der Fibrillen oder anderen histologischen Unregelmäßigkeiten im Faserverlauf zeigen sich korrespondierende Unregelmäßigkeiten des pyroelektrischen Achsenverlaufs.In genau korrespondierenden Abschnitten der gleichen Sehne verschiedener Individuen fand sich eine sehr erhebliche biologische Streubreite der pyro- und piezoelektrischen Effekte.In situ hatte das permanente elektrische Moment der untersuchten menschlichen und Rinder-Sehnen, sowie der Schwanzsehnen von Ratten eine festliegende gleichsinnige Vektorrichtung bei allen Individuen. Die Vektorrichtung war bei den untersuchten korrespondierenden Sehnen von Mensch und Rind sowie bei den Rattenschwanz-Sehnen analog.Die Vektorrichtung der permanenten elektrischen Polarisation bei Sehnengewebe, und wahrscheinlich auch bei anderen kollagenhaltigen Strukturen, scheint in Beziehung zur morphogenetischen Entwicklungsrichtung der Tiere zu stehen.
Unterstützt durch Sachbeihilfen der Deutschen Forschungsgemeinschaft. 相似文献
Summary Tendons are pyroelectric. Pyroelectrical behaviour is identical with a permanent electrical moment in the direction of the pyroelectrical axis. There exists a pyroelectrical (and consequently also piezoelectrical) axis corresponding to the longitudinal axis of the tendon fibres and their collagen fibrils, and also corresponding to their optical axis, in the direction of which a positive birefringence is known.Accordingly in tendons with an approximately parallel alignment of the collagen fibres the pyroelectrical (and piezoelectrical) axis corresponds to the physiological longitudinal tendon axis. In rope-like or any other histological irregular forms of the collagen fibre alignment corresponding irregularities of the electrical axis direction were found.The pyro- and piezoelectric effects show large biological variations in corresponding tendons of different individuals.In situ the permanent electrical moment in the examined tendons of men and ox and of rat-tail respectively is always in the same vector direction in each individual. This vector direction is analogical in all examined corresponding tendons of men, ox, and also in rat-tail. The permanent electrical moment of tendons (as well as of other collagen-containing tissues) seems to correspond to the morphogenetical development axis of animals.The results of this investigation may be understood by the assumption that the rod-like collagen molecule (i.e. tropocollagen) represents an electrical dipole with a permanent electrical moment in the longitudinal direction of the rod.
Unterstützt durch Sachbeihilfen der Deutschen Forschungsgemeinschaft. 相似文献
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Proteins assayed electrophoretically showed variation at only three of 49 presumed genetic loci in alligators from southwestern Louisiana. Average heterozygosity per individual was 0.021±0.012; proportion of polymorphic loci was 0.06. Data on the history, structure, and ecology of this alligator population are consistent with natural selection as the primary factor accounting for this low genetic variability. However, neither a historic population bottleneck nor some genetic mechanism limiting variability can be dismissed as a possible factor.The study was supported by NSF Grant BMS 73-0125 to H.C.D. 相似文献