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Fowl plague virus, strain Dutch, was metabolically labeled withd-[2-3H]mannose, or withd-[6-3H]glucosamine, and the small subunit (HA2; 0.8 mg in total) of the viral hemagglutinin was isolated by preparative sodium dodecylsulfate-polyacrylamide gel electrophoresis. After proteolytic digestion, the radioactive oligosaccharides were sequentially liberated from the glycopeptides by treatment with different endo--N-acetylglucosaminidases and with peptide:N-glycosidase or, finally, by hydrazinolysis. In this manner, four groups of glycans could be obtained by consecutive gel filtrations and were subfractionated by HPLC. The structures of the individual oligosaccharides were analyzed by micromethylation, by acetolysis or by digestion with exoglycosidases. The major species amongst the high mannose glycans at Ans-406 of the viral glycopolypeptide were found to be Man1-2Man1-3(Man1-2Man1-6)Man1-6(Man1-2Man1-2Man1-3)Man1-4GlcNac1-4GlcNAc and Man1-3(Man1-2Man1-6)Man1-6(Man1-2Man1-2Man1-3)Man1-4GlcNAc1-4GlcNAc, while the complex glycans at Asn-478 are predominantly GlcNAc1-2Man1-3(GlcNAc1-2Man1-6)Man1-4GlcNAc1-4GlcNAc (lacking, in part, one of the outerN-acetylglucosamine residues) and GlcNAc1-2Man1-3(Gal1-4GlcNAc1-2Man1-6)Man1-4GlcNAc1-4GlcNAc.Abbreviation BSA bovine serum albumin - endo D (F,H) endo--N-acetyl-d-glucosaminidase D (F,H) - HA hemagglutinin (HA1, large subunit of HA - HA2 small subunit - FPV fowl plague virus - PNGase F peptide:N-glycosidase F - SDS sodium dodecylsulfate  相似文献   
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Summary The autologous serologic reactivity of 13 patients with bladder cancer was evaluated using cell lines derived from each individual's own tumor as targets. Protein A and immune adherence assays were employed to determine antibody binding to the tumor targets at varying passage numbers. Autologous reactivity was found in 6 of the 13 cell lines tested. However, the titer was usually low regardless of the passage number. Seven autologous serum/cell line combinations were tested using both low and high passage cells as targets. In six of these combinations, the degree of antibody binding was similar with both low and high passage target cells. The incidence of autologous reactivity in the 12 patients with urothelial tumors was 50%.This investigation was supported by PHS Grant number CA36933, awarded by the National Cancer Institute, DHHS.  相似文献   
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Zusammenfassung In zwei Kerngebieten des Uhuvorkommens der Bundesrepublik Deutschland hat der Uhu in neuester Zeit scheinbar sehr stark zugenommen. In der Frankenalb (10 000 km2) schätzte man von 1955 bis 1964 etwa 30–40, Anfang der 70er Jahre etwa 50 und 1975–1980 75–83 Paare. In einem Ausschnitt der mittleren bayerischen Alpen (ca. 840 km2) waren um 1937 nur 3 Brutpaare bekannt, um 1975 mindestens 4; 1983/84 konnten jedoch mindestens 14 Brutpaare ermittelt werden. Die Zunahme ist zumindest größtenteils auf intensivere und systematische Kontrollen zurückzuführen. Der für die 30er Jahre vermutete Tiefstand des Bestandes in der Bundesrepublik dürfte weit höher gelegen haben als bisher vermutet, da zeitgenössische Quellen wahrscheinlich nur Teile des Bestandes erfaßten. Sicher lag der Bestand im 20. Jahrhundert wohl nie unter 50 Brutpaaren (bisherige Annahme 35), selbst zur Zeit des Minimums in der Bundesrepublik wahrscheinlich deutlich höher. Eine Obergrenze des bayerischen Brutbestandes von 200 Brutpaaren um 1980 ist durchaus realistisch. In den Alpen ist auch heute noch der Brutbestand völlig unzureichend bekannt. Das Aussetzen von Uhus hat in Bayern sicher keine Bedeutung für die Bestandsentwicklung gehabt. Der Median liegt für Todfunde ausgesetzter Uhus bei 0,43, für als Nestling beringte Wilduhus bei 1,9 Jahren. An Leitungen starben hochsignifikant mehr Wildvögel, an Straßen und Eisenbahnen dagegen hochsignifikant mehr ausgesetzte Vögel. Unterschiedliche Wanderneigung zwischen Wilduhus und ausgesetzten Vögeln ließ sich nicht sichern. Aussetzung und Wiedereinbürgerung sollten in Süddeutschland unbedingt unterbleiben und dürften auch im mittleren und nördlichen Deutschland mittlerweile überflüssig geworden sein. Eine Bestandsüberwachung und Kontrolle in ausgewählten Gebieten ist dagegen vordringlich.
Some remarks on long term trends in the breeding population of the Eagle Owl (Bubo bubo) in Bavaria
Summary In two centres of its distribution in the Federal Republic of Germany the Eagle Owl has increased remarkably in recent years. Between 1955 and 1965 the population of the Frankonian Jura (ca. 10 000 km2) was estimated between 30 and 40 pairs, at the beginning of the seventies about 50, and in 1975/80 about 75–83 pairs. In an area of the Bavarian Alps (ca. 840 km2) only 3 pairs were known in 1937, at least 4 in 1975. In 1983/84, however, a thorough examination revealed at least 14 pairs in this area. The increase in both areas is most likely due to intensive and systematic checks in recent years. The lowest population level in the FRG, supposed for the thirties, was probably higher than estimated so far as contemporary sources apparently did not cover the whole population. During the 20th century the population total of the FRG most likely has never been below 50 pairs and was probably higher even in times with minimum level. For 1980 an upper limit of 200 pairs in Bavaria seems to be realistic. In the Alps, however, the population size remains unsufficiently known even today. Release of captive bred birds didn't seem to have any increasing and stabilizing effect on the Bavarian population. The median for released birds found dead was 0,43, for wild chicks 1,9 years. Significantly more released birds died by traffic, whereas significantly more wild birds were victims of overhead lines. Differences in dispersal between wild and released birds seem likely, but could not be proved statistically. Releasing resp. reintroduction should be stopped in southern Germany; even in middle and northern Germany this conservation strategy seems to be unnecessary today. Survey and protection of breeding sites, however, should be continued or reorganized.
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In recordings from single tympanic receptor fibres in C. biguttulus, the response to synthesized sounds (rectangularly modulated white noise) interrupted by very brief (a few milliseconds) gaps was examined. In behavioral tests, females of the species respond very differently to such 'model syllables' at moderate intensities, depending on the gap width. If the gaps (in a moderate-intensity syllable) are larger than 2 ms, the stimulus fails to elicit a response, whereas stimuli with gaps smaller than 1 ms are as effective as uninterrupted syllables (D. von Helversen 1972; O. von Helversen 1979). Neither the mean spike count nor the interspike-interval distribution of the single receptor response contains the information sufficient to distinguish uninterrupted syllables from syllables with gaps. On the other hand, examination of the temporal distribution of the spikes reveals that gaps (or the pulse onsets following the gaps) cause spike synchronization. An index of synchronization (IS) was defined as a measure of this gap-induced effect. Analysis of the receptor responses based on IS revealed differences that correspond quantitatively to the abrupt abolition of the behavioral response at a gap-width between 1 and 2 ms. From the hypothesis that such brief gaps are detected by the nervous system by way of spike synchronization in the tympanic nerve, one can predict certain features of the behavioral response to high-intensity stimuli. The gap-induced spike synchronization was more pronounced at higher temperatures. This effect was demonstrated in both summated recordings from the tympanic nerve and single fibre recordings. Experiments with primary auditory fibres of Locusta migratoria showed that the receptors in this species respond very similarly to the same stimuli. That is, the receptors of C. biguttulus are not specially adapted for detecting very brief gaps. Synchronization of the spikes in parallel receptor fibres of the tympanal nerve is probably a general feature of acridids; we infer that in C. biguttulus this gap-induced synchronized activity is detected by special processing in higher auditory centres.  相似文献   
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Ecdysone was demonstrated by ultrastructural immunocytochemistry to be present in the mitochondria of the Y-organs of the crayfish Orconectes limosus. This is in remarkable contrast to the prothoracic glands of insects and suggests substantial differences in the biosynthesis of the same hormone, ecdysone, in crustaceans and insects.  相似文献   
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