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181.
In Vitro Release of Endogenous β- Alanine, GABA, and Glutamate, and Electrophysiological Effect of β-Alanine in Pigeon Optic Tectum 总被引:6,自引:6,他引:0
Gerhard Toggenburger Dominik Felix Michel Cuénod Hermann Henke 《Journal of neurochemistry》1982,39(1):176-183
The efflux of 20 amino acids, induced by either high K+ concentration or veratrine, was determined in pigeon tectal slices. Ca2+-dependent, K+-induced release of beta-alanine, gamma-aminobutyric acid (GABA), and glutamate was observed. Veratrine caused release of the same amino acids plus glycine in a tetrodotoxin-sensitive manner. beta-Alanine had a strong inhibitory effect on the activity of tectal neurons which was blocked by strychnine but not by bicuculline. The results indicated a transmitter function for beta-alanine in the optic tectum, and were consistent with the previously proposed transmitter role of GABA and glutamate in this structure. 相似文献
182.
Kurt Wüthrich Gerhard Wider Gerhard Wagner Werner Braun 《Journal of molecular biology》1982,155(3):311-319
A general scheme is proposed for the determination of spatial protein structures by proton nuclear magnetic resonance. The scheme relies on experimental observation by two-dimensional nuclear magnetic resonance techniques of complete throughbond and through-space proton-proton connectivity maps. These are used to obtain sequential resonance assignments for the individual residues in the amino acid sequence and to characterize the spatial polypeptide structure by a tight network of semi-quantitative, intramolecular distance constraints. 相似文献
183.
Herbert Tichy Traute Kleinschmidt Gerhard Braunitzer 《Journal of molecular evolution》1981,18(1):9-14
Summary The monomeric hemoglobins ofChironomus tentans andC. pallidivittatus have been isolated and separated into their respective components by gel chromatography on Sephadex G-75 and ion-exchange chromatography on DEAE-Sephacel. The amino acid compositions of the purified components are given. The sequence of the 30 N-terminal amino acid residues of one of the monomeric components (Hb I fromC. pallidivittatus) was determined and found to be identical in almost all of its parts with the monomeric hemoglobins ofC. thummi (CTT III and CTT IV).Antibodies against the monomeric hemoglobins Hb I and Hb IIc and the dimeric fraction were highly specific and no cross reaction between dimeric and monomeric hemoglobins could be demonstrated. The antibodies against the monomers crossreact with the monomeric hemoglobins CTT III and CTT IV ofC. thummi. Taken together with genetic data, the immunological results indicate that divergence of monomeric from dimeric forms was an early event in the evolution of the various hemoglobins inChironomus. 相似文献
184.
Gerhard Toggenburger Max H?sermann Beat Mütsch Giulio Genoni Markus Kessler Fritz Weber Dietrich Hornig Brigitte ONeill Giorgio Semenza 《生物化学与生物物理学报:生物膜》1981,646(3):433-443
l-Ascorbate is taken up into brush border vesicles from kidney cortex of rat, rabbit and guinea pig by an efficient, Na+-dependent and potential-sensitive transport process. This uptake shows saturation () and is strongly stimulated by low concentrations of N3?. Erythorbate (d-isoascorbate) seems to be another, but poorer, substrate of the same transporter. 相似文献
185.
Zusammenfassung Der Gesang von Blaumeisen-Populationen in Mitteleuropa, Spanien, Marokko und auf Teneriffa wurde miteinander verglichen (Abb. 1). In Süddeutschland und auf Teneriffa wurden Klang-Attrappen-Versuche durchgeführt.1. Der Blaumeisen-Gesang ist in Marokko und auf Teneriffa sehr ähnlich. Er unterscheidet sich vom Blaumeisengesang in Europa (Mitteleuropa und Spanien) in folgenden Eigenschaften (2.–4.):2. Ihm fehlen phrasierte Strophen (Abb. 2 a–c, e, 3, 4 a, b, f, g), also Strophen, in denen dasselbe Element mindestens viermal nacheinander wiederholt wird.3. Er enthält mehr verschiedene Elemente (Abb. 5, 7).4. Die interindividuelle Variation ist größer (Abb. 6, 7).5. Die Unterschiede zwischen dem Blaumeisen-Gesang in Europa und auf Teneriffa lassen sich nicht mit der Kontrast-Betonungs- und der Kontrast-Verlust-Hypothese nachLack &Southern (1949) undMarler (1960) erklären. Die Lernentzugs-Hypothese erklärt sie besser.6. Die Blaumeisen von Teneriffa und Marokko sind sehr nahe miteinander verwandt, aber vermutlich sind sie von den europäischen Blaumeisen artlich nicht getrennt.
Für die Übersetzung danken wir FrauR. Jellis und HerrnP. Lundberg. 相似文献
The song of the Blue Tit (Parus caeruleus) on Tenerife: Experiments on a presumed loss of contrast
Summary Songs of Blue Tit populations from Central Europe, Spain, Morocco and Tenerife (fig. 1) were compared. Playback experiments were made in South Germany and on Tenerife.1. Blue Tit songs from Morocco and Tenerife are very similar. They differ from songs of Blue Tits in Europe (Central Europe and Spain) in the following characteristics (2–4):2. Lack of phrased songs (fig. 2 a–c, e, 3, 4 a, b, f, g), i. e. songs with the same notes repeated successively at least four times.3. A greater number of different types of notes (fig. 5, 7).4. Greater interindividual variation (fig. 6, 7).5. Differences between Blue Tit song from Europe and from Tenerife cannot be explained by the hypothesis of contrast reinforcement and loss of contrast, according toLack &Southern (1949) andMarler (1960). The withdrawal of learning hypothesis is a better explanation.6. Blue Tits on Tenerife and Morocco are very closely related to each other but are probably not a different species from the Blue Tits of Europe.
Für die Übersetzung danken wir FrauR. Jellis und HerrnP. Lundberg. 相似文献
186.
A chicken pectoralis muscle membrane fraction enriched in a Mg2+- or Ca2+-activated (‘basic’) ATPase was obtained by sucrose gradient centrifugation. Enzymatic properties of the ‘basic’ ATPase were determined and used to localize its enzymatic activity in situ by ultrastructural cytochemistry. The enzyme was activated by Mg2+ or Ca2+ but not by Sr2+, Ba2+, Co2+, Ni2+ or Pb2+. It was present in a membranous fraction with a buoyant density of 1.10-1.12 (24–27.5% (w/w) sucrose). ‘Basic’ ATPase activity had a sedimentation pattern similar to the putative plasma membrane enzymes, 5′-nucleotidase and leucyl β-naphthylamidase, but different from that of sarcoplasmic reticulum Ca2+ ATPase. Also unlike sarcoplasmic reticulum Ca2+ ATPase, ‘basic’ ATPase was resistant to N-ethylmaleimide and aldehyde fixatives, was active in a medium containing a high Ca2+ concentration (3 mM), and was lost when exposed to Triton X-100 or deoxycholate. In cytochemical studies, a low Pb2+ concentration was used to capture the enzymatically released phosphate ions. Under conditions which eliminated interfering (Na+ + K+) ATPase and sarcoplasmic reticulum Ca2+ ATPase activities, electron-dense lead precipitates were present at the plasmalemma and T-system membranes. These studies suggest that ‘basic’ ATPase activity is associated with plasmalemma and T-system membranes of skeletal muscle. 相似文献
187.
188.
189.
Gerhard Fürstenberger Friedrich Marks 《Biochemical and biophysical research communications》1978,84(4):1103-1111
The proliferative response of mouse epidermis to the phorbolester TPA (10 nmoles) in vivo is completely inhibited by a single topical application of indomethacin one hour before TPA. DNA labeling in normal mouse epidermis is not significantly depressed by the drug. The inhibition can be reversed by applying prostaglandin E2 (>3 nmoles) simultaneously with TPA, whereas prostaglandin F2α (100 nmoles) is ineffective. The indomethacin-sensitive event is restricted to the first hour after phorbol ester treatment. TPA-induced skin inflammation is not influenced by the drug. It is proposed that prostaglandin E2, or a closely related compound, mediates the mitogenic effect of TPA in mouse skin. 相似文献
190.
l-(+)-Bornesitol was detected in 23 of 33 genera of Gentianaceae investigated. The only subtribe without l-(+)-bornesitol (3 species tested) was Exacinae. None of the five genera of Menyanthaceae examined were found to contain l-(+)-bornesitol. 相似文献