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1.
Protection of Mice against Lethal Coxsackievirus B3 Infection by Using DNA Immunization 总被引:27,自引:0,他引:27 下载免费PDF全文
Andreas Henke Elke Wagner J. Lindsay Whitton Roland Zell Axel Stelzner 《Journal of virology》1998,72(10):8327-8331
Vaccination with DNA and recombinant vaccinia viruses (rec.VV) has been studied with the coxsackievirus B3 (CVB3) model system. Plasmids encoding all structural proteins of CVB3, when injected intramuscularly, induced only low levels of virus-specific antibodies. However, DNA vaccination with the major structural protein VP1 protected 72.2% of mice from lethal challenge, whereas VP1 expressed by rec.VV was much less efficient. 相似文献
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Jean-Michel Panoff Bouachanh Thammavongs Jean-Marie Laplace Axel Hartke Philippe Boutibonnes Yanick Auffray 《Cryobiology》1995,32(6)
The physiology of the cold-shock response in Lactococcus lactis subsp. lactis IL1403 at a subzero temperature, and cold-induced adaptation to heat shock, were investigated. Preincubation of cells at 8°C led to the development of cryotolerance, i.e., an enhanced capacity to survive exposure to freezing temperature (-20°C). Pretreatment with chemicals considered to be chaotropic agents did not induce cryotolerance or, in contrast, led to a decrease in survival capacity at -20°C. Interestingly, preincubation at 8°C led also to thermololerance to a 52°C challenge, but preincubation of cells at 42°C for 30 min did not improve their capacity to survive freezing-thawing exposure. These results demonstrate that cold- and heat-shock responses are physiologically linked by a complex relation. Furthermore, food processing at low temperature before subzero or heat treatment may need to be reconsidered. 相似文献
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N-Terminal Sequence of Pig Brain Choline Acetyltransferase Purified by a Rapid Procedure 总被引:6,自引:5,他引:1
Axel Braun Yves-Alain Barde Friedrich Lottspeich Werner Mewes Hans Thoenen 《Journal of neurochemistry》1987,48(1):16-21
A procedure is reported that allows the purification and amino terminal sequencing of pig brain choline acetyltransferase. The enzyme (present in extremely low amounts in this tissue) is eluted together with its antibody from an affinity column by a mild pH shift and the resulting enzyme-antibody complex separated by gel electrophoresis. The band corresponding to the enzyme is electroeluted from the gel using volatile solutions allowing the direct determination of the amino acid composition and partial sequence. The first 11 residues are: Pro-Ile-Leu-Glu-Lys-Thr-Pro-Pro-Lys-Met-Ala. 相似文献
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A method for the prediction of hydrogen positions in proteins is presented. The method is based on the knowledge of the heavy atom positions obtained, for instance, from X-ray crystallography. It employs an energy minimization limited to the environment of the hydrogen atoms bound to a common heavy atom or to a single water molecule. The method is not restricted to proteins and can be applied without modification to nonpolar hydrogens and to nucleic acids. The method has been applied to the neutron diffraction structures of trypsin ribonuclease A, and bovine pancreatic trypsin inhibitor. A comparison of the constructed and the observed hydrogen positions shows few deviations except in situations in which several energetically similar conformations are possible. Analysis of the potential energy of rotation of Lys amino and Ser, Thr, Tyr hydroxyl groups reveals that the conformations of lowest intrinsic torsion energies are statistically favored in both the crystal and the constructed structures. 相似文献
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Summary Leu-enkephalin containing secretory granules were demonstrated in axon terminals of immunogoldlabeled electron-microscopic sections of the sinus gland of three brachyuran crustaceans. These granules have a diameter of 120+-15 nm and differ in electron density from those located in adjacent terminals containing hyperglycemic or molt-inhibiting hormone. These neurohormones do not show co-localization with leu-enkephalin. The cross-reactivity of leu-enkephalin antiserum with met-enkephalin is less than 1%. The sinus glands of the three species examined show no immunoreactivity for FMRF-amide. A modulatory activity of endogenous enkephalin by paracrine mechanisms is suggested. 相似文献
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A coiling-inducing factor was isolated from tendrils of Bryonia dioica Jacq. and identified by infrared, 1H-, 13C-nuclear magnetic resonance and mass spectrometry as -linolenic acid. When applied to detached tendrils, exogenous -linolenic acid, but not linoleic acid or oleic acid, induced tendril coiling. Further investigations showed that metabolites of -linolenic acid, jasmonic acid and, even more so, methyljasmonate, are highly effective inducers of tendril coiling in B. dioica. Methyljasmonate was most active when administered by air and, in atmospheric concentrations as low as 40–80 nM, induced a full free-coiling response with kinetics similar to mechanical stimulation. Even atmospheric levels as low as 4–5 nM methyljasmonate were still found to be significantly active. Methyljasmonate could be one of the endogenous chemical signals produced in mechanically stimulated parts of a tendril and, being highly volatile, act as a diffusible gaseous mediator spreading through the intracellular spaces to trigger free coiling of tendrils.Abbreviations EI-MS
electron impact-mass spectrometry
- HPLC
high-performance liquid chromatography
- IAA
indole-3-acetic acid
- NMR
nuclear magnetic resonance
- TFA
trifluoroacetic acid
We are indebted to the Deutsche Forschungsgemeinschaft, Bonn and the Fonds der Chemischen Industrie, Frankfurt (literature provision) for their support and to Dr. C. Brückner, Halle, for jasmonic-acid determinations. 相似文献
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Detection of MR signals with surface coils provides increased signal-to-noise ratio for superficial structures relative to detection by circumferential coils, permitting improved spatial resolution. Different geometries of surface coils can be used for different regions. Coils that are flat or curved to fit body contours are good for general imaging, with a range of coil sizes useful for structures of different size or depth. Solenoidal coils are useful for imaging protruding structures such as breasts, while smaller versions of conventional circumferential coils that can be slipped over limbs are useful for imaging extremities. 相似文献
10.
Isaksson Axel Philips Anna–Carin Göransson Eva Björkenfeldt Henrik 《Acta veterinaria Scandinavica》1987,28(3-4):455-457
The electrical conductivity (EC) of milk is mainly a function of the electrolyte concentration in the milk and therefore raised in mastitis. The present investigation was aimed at elaborating, if possible, a diagnostic model for screening purposes based on EC determinations and consistent with the diagnostic procedures and interpretations commonly used in laboratory milk diagnosis in the Nordic countries (Klastrup 1975). According to this diagnosis (here called reference diagnosis) cell numbers above 300,000/ml (cell count or the corresponding CMT-score) in foremilk quarter samples during the main part of the lactation period and significantly above the lowest value on within-udder comparison during late lactation are considered indicative of mastitis and bacteriological examinations are made when called for. 相似文献