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1.
Bier  Karlheinz 《Chromosoma》1965,16(1):58-69
Summary The influence of O2-deprivation and reduction of temperature on the incorporation of the RNA-precursors 3H-uridine und 3H-cytidine is investigated in various tissues of the larvae and in the ovaries of adults of the housefly Musca domestica L. While RNA-synthesis in most of the tissues is strongly reduced under anaerobic conditions, synthesis continues in a moderate extent in muscle cell nuclei and nurse cell nuclei. The RNA-macromolecules (mRNA and rRNA), however, do not migrate into the cytoplasma. RNA-synthesis within the cell nucleus is less affected by a sudden reduction of temperature than the passage of RNA through the nuclear membrane which is reduced to a very low rate. The macromolecular RNA, therefore, does not diffuse into the cytoplasma but is transported actively through the nuclear envelope. The malformations caused by anaerobiosis during embryogenesis are brought in connexion with the active RNA-transport through the nuclear envelope and the separation of transport and synthesis.

Herrn Professor Dr. Hans Bauer zum 60. Geburtstag gewidmet.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

2.
Summary Within an population sample of 300 individuals of Southwestern Germany the red cell acid phosphatase polymorphism is investigated. Gene frequency estimates are: Pa=0.31, Pb=0.643, Pc=0.047.

Direktor: Prof. Dr. med. Dr. H. Baitsch

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

3.
Summary The fine structure of the cerebral gland of the fresh water snail Planorbarius corneus has been described. The apical cell surfaces of the epithelium bordering the lumen are covered with short microvilli and in some parts with cilia. There is a remarkable enlargement of the basal surface of those cells underlying the perineurium by long branched cell processes. The fine structure and density of the substances in the lumen differ; inclusions of paracrystallin structure are found. The possible functional significance of these organs in Pulmonates is discussed.

Frau Prof. Dr. B. Scharrer zum 60. Geburtstag gewidmet.

Mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

4.
Summary Young isolated apical initials of Stypocaulon scoparium usually regenerate in a bipolar way. Older initials after having produced the basal cell of a branch are reduced in their regenerating capacity to unipolarity, i. e. after each division the polarity of the apical cell must be newly induced.

Herrn Prof. Dr. R. Harder zum 80. Geburtstag gewidmet.  相似文献   

5.
Summary The effectiveness of recurrent selection vs. continuous inbreeding in improving smut resistance of a very susceptible flint corn was studied. Two cycles of recurrent selection were performed, and S 6 generation was reached in the inbreeding series.
Zusammenfassung Mit dem Ziel der Verbesserung der Brandresistenz wurde die Wirksamkeit rekurrenter Selektion gegenüber fortgesetzter Inzucht an einem sehr anf?lligen Hartmais untersucht. Die rekurrente Selektion wurde in zwei Zyklen durchgeführt, bei der Inzuchtserie wurde die S 6-Generation erreicht.


Dedicated to Dr. George F. Sprague on the occasion of his 65th birthday.  相似文献   

6.
Summary Adenylate kinase phenotypes were determined in 407 unrelated persons from Southwestern germany. The frequencies were estimated to be AK1=0.969, AK2=0.031.

Direktor: Prof. Dr. med. Dr. H. Baitsch

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

7.
Zusammenfassung Die licht- und elektronenmikroskopische Untersuchung des Reissnerschen Fadens bei Pristella riddlei Meek und Larven von Salamandra salamandra terrestris zeigt im gesamten Verlauf des Reissnerschen Fadens Anlagerungen von Zelldetritus. Durch diese Beobachtung wird Olssons Theorie einer Transportfunktion des Reissnerschen Fadens gestützt.
Summary In a light and electron microscope study on Reissner's fibre of Pristella riddlei Meek and larvae of Salamandra salamandra terrestris it is shown, that there are appositions of cell detritus in the whole length of Reissner's fibre. This observation supports Olsson's theory of a transport function of Reissner's fibre.


Großenteils im Institut für Histologie und experimentelle Biologie der Universität München (Direktor: Professor Dr. med. R. Bachmann) und mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt.  相似文献   

8.
Zusammenfassung Die komplizierten, bipektinaten Osphradien der NeogastropodenBuccinum undatum undNeptunea antiqua sind durch folgende Zelltypen gekennzeichnet: Die hochprismatischen Stützzellen stellen den Hauptteil des mehrreihigen Osphradialepithels und sind durch ein reich ausgebildetes Villussystem sowie zahlreiche Pigmentgranula charakterisiert. Bisweilen tragen sie Zilien. Mindestens zwei Schleimzelltypen lassen sich unterscheiden. Den verschiedenen Sinneszelltypen lassen sich zwei Funktionen zuordnen: der Chemorezeption und dem Tastsinn. Die Funktion eines weiteren Typs mit stark ausgebildetem glattem endoplasmatischem Reticulum bleibt unbekannt.
The osphradium of the prosobranch gastropods Buccinum undatum L. and Neptunea antiqua (L.)
Summary The complicated, bipectinate osphradia of the NeogastropodsBuccinum undatum andNeptunea antiqua are characterized by the following cell types: The columnar supporting cells of the pseudostratified epithelium form the bulk of the epithelial cells and exhibit a profusely developed system of microvilli and an abundance of pigment granules. Occasionaly they are ciliated. At least two types of mucous cells can be distinguished. The different types of sensory cells can be associated with two functions: chemoreception and touch appreciation. An additional sensory cell type with a well developed system of smooth endoplasmic reticulum cannot be related to any particular function.


Die Untersuchungen wurden mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt.

Herrn Prof. Dr.A. Kaestner (München) danken wir für Literaturhinweise.

Herrn Prof. Dr.W. Bargmann danke ich für einen Arbeitsplatz im elektronenmikroskopischen Laboratorium des Anatomischen Instituts Kiel.  相似文献   

9.
Zusammenfassung In sauren methanolischen Extrakten aus gametophytischem Gewebe vonLophocolea bidentata (L.)Dum. undPlagiochila asplenioides (L.)Dum. konnte zum ersten Male Ellagsäure mit Hilfe dünnschichtchromatographischer Methoden identifiziert werden. Daneben fanden sich in den Extrakten noch einige andere bisher noch nicht identifizierte Phenole, darunter möglicherweise 8 Flavonoide.
Summary Ellagic acid was detected in acidic methanol-extracts of gametophytic tissue ofLophocolea bidentata (L.)Dum. andPlagiochila asplenioides (L.)Dum. The identification was accomplished by thin-layer Chromatographic methods. Beside this compound some more still unidentified phenolics were found, among those probably 8 flavonoids.


Herrn Prof. Dr. L.Brauner, mit den herzlichsten Wünschen zum 75. Geburtstag gewidmet.

Herrn Prof. Dr. H.Jork von der Fachrichtung Pharmakognosie und Analytische Phytochemie sowie Fräulein S.Klein danken wir sehr für die Hilfe bei der Herstellung der UV-Spektren. Herrn grad. biol. et chem. S.Bartl danken wir für hilfreiche Diskussion.  相似文献   

10.
Zusammenfassung Aus Kulturen zweier Streptomycetenstämme wurde das l-2,5-Dihydrophenylalanin (I) isoliert. Die antibiotische Wirkung dieser Verbindung kann durch Phenylalanin und Tyrosin aufgehoben werden.
Metabolic products of microorganisms87. l-2,5-dihydrophenylalanine
Summary l-2,5-Dihydrophenylalanine has been isolated from cultures of two strains of Streptomyces. The antibiotic activity of this compound is antagonized by Phenylalanine and Tyrosine.


86. Mitteilung: W. Keller-Schierlein und W. Richle: Antimicrobial Agents and Chemotherapy 1970 (im Druck).

Jetzt: Gesellschaft für Molekularbiologische Forschung mbH., Stöckheim bei Braunschweig.  相似文献   

11.
Zusammenfassung Es wurde die Wirkungsweise von Borrelidin untersucht und mit zwei Makrolid-Antibiotica verglichen. Borrelidin hemmt in einem zellfreien System aus Bacillus subtilis spezifisch den Einbau von Threonin in sRNS bei einer Konzentration von 1,4·10-6 m. Hingegen hemmen die Makrolid-Antibiotica Lankamycin (neutral) und Erythromycin (basisch) bei Konzentrationen, die zehnmal höher liegen als die wachstumshemmende Konzentration, nicht die Verknüpfung von Threonin oder anderer Aminosäuren mit sRNS.In Zellen hemmt Borrelidin bei einer Konzentration von 1,5–3·10-6 m die Synthese von Protein, RNS und DNS. Lankamycin und Erythromycin hingegen hemmen nur die Synthese von Protein.Es wird vermutet, daß Borrelidin das erste Antibioticum ist, das die Protein-synthese über die Hemmung des Einbaus von Aminosäuren in sRNS blockiert.
Metabolic products of microorganisms. 62nd information the inhibition of the attachment of threonine to sRNA in a cell-free system and of the sythesis of protein and nucleic acids in the cell by the antibiotic borrelidin
Summary The mode of action of borrelidin has been studied and compared with two macrolide antibiotics. Borrelidin specifically inhibits the attachment of threonine to sRNA at a concentration of 1,4·10-6 m in a cell-free system of Bacillus subtilis. However, the macrolide antibiotics lankamycin (neutral) and erythromycin (basic), at concentrations which are ten times higher than those required to inhibit growth, still do not inhibit the binding of threonine or other amino acids to sRNA.In cells borrelidin inhibits at concentrations of 1.5–3·10-6 m the synthesis of protein, RNA and DNA. In this point as well borrelidin acts differently from lankamycin and erythromycin which inhibit the synthesis of protein selectively.It is supposed that borrelidin is the first antibiotic inhibiting protein synthesis via amino acid attachment to sRNA.


61. Mitt.: B. Maurer, A. Müller, W. Keller-Schierlein u. H. Zähner: Ferribactin, ein Siderochrom aus Pseudomonas fluorescens Migula. Arch. Mikrobiol. 60, 326–339 (1968).  相似文献   

12.
Résumé Les larves deTrichoplusia ni (Hübner) infectées parVairimorpha (=Nosema) necatrix (Kramer) présentent des sympt?mes chroniques, semi-chroniques et aigus selon les doses de spores deV. necatrix (5 à 500, 5.103 à 5.105 et 5.106 par larve, respectivement) ingérées par larve.V. necatrix parasite principalement le corps adipeux et les tissus des muscles quand les larves ont des sympt?mes chroniques, tandis que les larves manifestent les sympt?mes aigus lorsque les microsporidies attaquent principalement l’intestin moyen. L’histopathologie de la maladie est étudiée.
Summary Infection of larvae ofTrichoplusia ni (Hübner) byVairimorpha, (=Nosema) necatrix was classified as chronic, semi-chronic and acute symptoms depending on the quantity of spores (5 to 500, 5×103 to 5×105, and 5×106 per larva, respectively) ingested per larva.V. necatrix infects mainly the fat body and some muscle tissue of larvae with chronic symptoms and mainly midgut tissue of larvae with acute symptoms.V. necatrix caused death in 3 to 4.5 days when a larva ingested 5×106 spores. The histopathology of the disease was studied.


Ce travail a fait l’objet d’une thèse de 3e cycle, présentée à l’Université de Paris VI en mars 1977, parWei Hsuang Chu.  相似文献   

13.
The scent-production and the scent-delivery in the posterior larval gland of the cotton bug Dysdercus intermedius Dist. was explored by means of light microscopy and electron microscopy.

Mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft.

Herrn Prof. Dr. R. Danneel danke ich für beratende Hilfe. Für die Anfertigung der elektronenmikroskopischen Aufnahmen stellte mir freundlicherweise Herr Prof. Dr. E. Scholtyseck das Mikroskop Zeiss EM 9A zur Verfügung. Fräulein Karin Wenzelmann und Fräulein Barbara Vogt danke ich für technische Assistenz.

Herrn Prof. Dr. Dr. R. Lermensick zum 70. Geburtstag gewidmet.  相似文献   

14.
Summary The decomposition of peptone and the associated species numbers and individual counts of ciliates has been investigated in flowing (current speed 40 cm/sec) and stagnant model ecosystems. In order to imitate the ecological conditions in natural waters receiving sewage small quantities of peptone were added at regular intervals.The most important environmental factors such as pH, dissolved oxygen, NH4 +-, NO3 --levels, and the organisms occurring in the free water as well as in the periphyton community on microscopic slides, were investigated for three weeks. Both the population dynamics of organisms and the environmental conditions within the ecosystems are figured (Figs. 1–6).The ecosystem with flowing water, and the aerated stagnant model showed high contents of O2 and fast mineralisation of peptone up to the NO3 --level. The unaerated model showed a retarded decomposition of peptone and accumulation of ammonia.The unaerated stagnant ecosystem showed the highest individual counts of bacteria and ciliates, while in the flowing model a limited number of organisms only was found.Most of the differences between flowing and stagnant waters are due to the varying O2-level. Only two species were directly inhibited by the current speed tested in these experiments.

Zoologisches Institut der Universität Bonn Hydrobiologische Arbeitsgruppe (Leiter: Prof. Dr. H. Bick)

Mit Untersützung der Weltgesundheitsorganisation.

Herrn Prof. Dr. Rolf Danneel zum 70. Geburtstag gewidmet.

Anschrift der Verfasser: PProf. Dr. H. Bick und Diol. Biol. W. Schmerenbeck, Hydrobiologische Arbeitsgruppe am Zoologischen Institut der Universität, D05300 Bonn 1, Poppelsdorfer Schlo\.  相似文献   

15.
    
Summary Two classes of partial revertants of 00-type mutants in the pyruvate dehydrogenase system ofEscherichia coli K 12 could be distinguished enzymatically and genetically. In one class of these strains the second mutation has occurred at or near the primary 00 site. The partial revertants of this class synthesize a pyruvate dehydrogenase complex containing a defective carboxylase component. The strains of the other class proved to be suppressed 00-type mutants,the second mutation having occurred outside the acetate locus on the E. coli chromosome. One of the suppressor alleles was found to be specific for a certain 00 site; it did not act on another genetically distinguishable 00 site nor on any of the tested mutant sites in the pyruvate dehydrogenase genes. The suppressed 00 type strains synthesize only small amounts (about 1/50 of wild type) of pyruvate dehydrogenase with a carboxylase component which so far could not be distinguished from the wild type carboxylase. In addition, the suppressor gene mutants produce a partial complex of the pyruvate dehydrogenase which lacks the carboxylase component. It is not yet known whether or not this situation represents a disproportional synthesis of the constituent enzymes of the pyruvate dehydrogenase complex, i.e., production of smaller amounts of the carboxylase than required for the formation of the enzyme complex.The results are discussed regarding their significance for the regulation of protein biosynthesis inE. coli in connection with similar data of other authors (Jacob andMonod 1961;Beckwith 1963, 1964) obtained with the lactose system of the same organism.

Mit 2 Textabbldungen  相似文献   

16.
Summary The author reports on the clinical and mycological studies of a case of black-grain maduromycosis in a woman from Santa Maria (Province of Catamarca, Argentine).Cultures of black grains in Sabouraud medium have developed colonies ofMadurella mycetomi and also ofMadurella grisea Mackinnon, Ferrada &Montemayor, 1949.The author questioned, which of the two species is the etiological agent in the present case and he concluded that the microscopic aspect of the black grain permits to suppose thatMadurella mycetomi is the agent in this case.

En homenaje al Prof. Tibor Benedek.  相似文献   

17.
W. Laux 《BioControl》1964,9(3):293-298
Summary Two types of larvae ofMalacosoma neustria (L.) different in their behaviour as well as in their activity, produce also layers of hemocytes of different thickness after parasitization by the tachinidMericia ampelus wilk. A nuclear polyhedrosis that occurred simultaneously killed both larval types at different speed. The possibility is discussed that the quality of the hemocyte reaction to parasitization depends not only directly on the larval type, but also indirectly through the polyhedrosis.

Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.

Herrn WOR Dr. J. M.Franz danke ich für wertvolle Anregungen und jederzeitige Unterstützung der Arbeit.  相似文献   

18.
I. Moore  A. Navon 《BioControl》1964,9(2):181-185
Résumé Un milieu artificiel pour l'élevage deProdenia litura F. est décrit sur lequel six générations successives de cette noctuelle furent élevées collectivement et deux individuellement. La fermeture du cycle biologique de larve néonata à larve néonate fut également obtenue sur ce milieu dans le cas d'Agrotis ypsilon Rott. etCyrphis unipuncta Haw.

Contribution from The Volcani Institute of Agricultural Research, Rehovot, Israel. 1964 Series, No. 679-E.

Division of Entomology, the Volcani Institute of Agricultural Research Rehovot.  相似文献   

19.
Summary Action potentials from single visual cells of the compound eye are lead off during illumination of the retina of Calliphora erythrocephala by means of intracellular capillary microelectrodes. The size of the monophasic and depolarizing action-potentials depends on light-intensity and on plane of polarized light. Turning the plane of polarization from maximum to minimum efficacy equals a decrease of intensity of about 50%. As the dioptric apparatus is optically isotropic, the experiments described here prove the hypothesis of Autrum and Stumpf, namely that the single visual cell responds to different planes of polarization with different states of excitation.

Die Untersuchungen wurden von der Deutschen Forschungsgemeinschaft unterstützt.  相似文献   

20.
Summary Two new species of the genusBinodoxys Mackauer 1960 and one new species of the genusLipolexis Foerster 1862 (Hymenoptera: Aphidiidae) from the Oriental region are described. All parasites have been reared from aphids onCitrus. A key is given for the known species of the genusLipolexis Foerster.

22. Beitrag zur Kenntnis derAphidiidae.  相似文献   

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