TY - JOUR A1 - Bringmann, Gerhard A1 - Zagst, Rainer A1 - Schöner, Bernd A1 - Busse, Holger A1 - Hemmerling, Martin A1 - Burschka, Christian T1 - Acetogenic Isoquinoline Alkaloids. XXIII. Structure of the Naphthyl Isoquinoline Alkaloid Dioncophylline A N2 - No abstract available KW - Chemie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31331 ER - TY - JOUR A1 - Albert, Bernhard A1 - Berning, Wilfried A1 - Burschka, Christian A1 - Hünig, Siegfried A1 - Martin, Hans-Dieter A1 - Prokschy, Frank, T1 - Transanulare Wechselwirkung des Azo-Chromophors inisodrinanalogen Systemen T1 - Transanular Interactions of the Azo Chromophore in Isodrin-type Systems N2 - No abstract available KW - Chemie Y1 - 1981 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31328 ER - TY - JOUR A1 - Fiala, Brigitte A1 - Linsenmair, Karl Eduard A1 - Maschwitz, Ulrich T1 - Diversität von Interaktionen zwischen Ameisen und Pflanzen im südostasiatischen Regenwald T1 - Diversity of ant-plant interactions in south-east Asian rainforests N2 - Assoziationen von Ameisen mit Pflanzen (und oft noch mit pflanzensaugenden Insekten als drittem Partner) dürften eine Ursache des Artenreichtums und der hohen Abundanzen tropischer Formicidae sein. Die von den Ameisen genutzten Pflanzen bieten entweder Nahrung an, über extraflorale Nektarien und/oder Nährkörperchen, oder aber - bei den eigentlichen Myrmekophyten - Nistraum und z.T. auch Nahrung. Diese Beziehungen zeichnen sich durch unterschiedliche Nutzungsweisen und Nutzungsintensitäten und damit stark differierende Abhängigkeit der Partner voneinander aus. Ein besonders breites Spektrum von Ameisen-Pflanzen-Assoziationen finden wir in der paläotropischen Baumgattung Macaranga (Euphorbiaceae), die sich daher als Modellsystem für vergleichende Untersuchungen hervorragend eignet. Die Grundfrage unserer Untersuchungen an diesem System lautet: Verläuft aufgrund der ausgeprägt mosaikartigen Verteilung der von den myrmekophilen Pflanzen angebotenen Nahrungs- und Nistraumressourcen die Neu- und Wiederbesiedlung von Habitaten durch die Ameisen in Form von Zufallsprozessen? Oder werden, im Gegenteil, durch diesen Umstand Spezialisierungen seitens der Ameisen gefördert und die Zusammensetzung der Lebensgemeinschaften dadurch stärker deterministisch geprägt? Unsere bisherigen Untersuchungen zeigen, daß beide Prinzipien wirken. Bei der alleinigen Nutzung von Nahrungsressourcen fehlen spezialisierte Beziehungen weitgehend und stochastische Ereignisse dürften sehr häufig die Pflanzen-Ameisen-Assoziation bestimmen. Bei den eigentlichen Myrmekophyten hingegen ist die Auswahl der assozierten Ameisen viel stärker determiniert, ganz besonders dann, wenn der Wohnraum, den die Pflanze offeriert, nur durch aktives Öffnen seitens der Ameisen erschlossen werden kann. N2 - Associations of ants with plants can be regarded as one reason for the high abundance and diversity of ants in the tropics. The plants either provide food as extrafloral nectar and/or food bodies or, in the true myrmecophytes, nesting space and partly also food. These associations are characterized by very different forms and intensities of use of the plant resources and, therefore, also varying mutual dependency of the partners. A broad spectrum of different ant-plant associations is found in the paleotropical tree genus Macaranga (Euphorbiaceae) wh ich is therefore especially suited as a model system for a comparative investigation. The central question of our studies is: Does the mosaic character of the spatial distribution of food and nesting resources provided by the myrmecophilous plants rather favour stochastic processes during colonization of habitats by ants? Or does it, on the contrary, preferentially lead to strong specializations in the ants? Our investigations show that both principles are realized. In interactions where ants only use the food resources, specific relationships are lacking and stochastic events direct the associations. In obligate myrmecophytes, however, the colonization largely follows deterministic principles, especially when nesting space inside the plant actively has to be made accessible by the ants. Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32894 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Sommerville, John A1 - Müller, Ulrike T1 - DNA is assembled into globular supranucleosomal chromatin structures by nuclear contents of amphibian oocytes N2 - The assembly of DNA into nucleosomal and supranucleosomal chromatin structures has been studied (i) by injection of circular DNA molecules (plasmids) into nuclei of Pleurodeles waltlii oocytes; and (ii) by in vitro incubation of plasmid molecules with the supernatant fraction from oocyte nuclei of Pleurodeles and Xenopus laevis, followed by purification of nucleoprotein structures formed with sucrose gradient centrifugation. [n both types of experiments , spread preparations of the newly assembled and transcriptionally inactive chromatin , examined by electron microscopy , show dense globular higher order (supranucleosomal) packing forms. Under partially relaxing (low salt) preparation conditions granular chromatin subunits of about 30 nm diameter can be seen either as widely spaced particles or in closely packed aggregates. The transcriptionally inactive endogenous chromatin of chromomeres of lampbrush chromosomes is arranged in similar higher order chromatin units. A correlation is found between the sizes of the DN A molecule probes used and the numbers of nucleosomes and higher order globules in the assembled chromatin structures. After prolonged dispersion in low salt buffers , these globular chromatin units unfold into chains of7-12 nucleosomes. The results support the concept that chromatin is arranged , under physiological ion concentrations as they are present in the nucleus , in supranucleosomal units of globular morphology. Y1 - 1980 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39671 ER - TY - JOUR A1 - Hügle, Barbara A1 - Hazan, Rachel A1 - Scheer, Ulrich A1 - Franke, Werner W. T1 - Localization of ribosomal protein S1 in the granular component of the interphase nucleolus and its distribution during mitosis N2 - Using antibodies to various nucleolar and ribosomal proteins, we define, by immunolocalization in situ, the distribution of nucleolar proteins in the different morphological nucleolar subcompartments. In the present study we describe the nucleolar localization of a specific ribosomal protein (51) by immunofluorescence and immunoelectron microscopy using a monoclonal antibody (R5 1-105). In immunoblotting experiments, this antibody reacts specifically with the largest and most acidic protein of the small ribosomal subunit (51) and shows wide interspecies cross-reactivity from amphibia to man. Beside its localization in cytoplasmic ribosomes, this protein is found to be specifically localized in the granular component of the nucleolus and in distinct granular aggregates scattered over the nucleoplasm. This indicates that ribosomal protein 51, in contrast to reports on other ribosomal proteins, is not bound to nascent pre-rRNA transcripts but attaches to preribosomes at later stages of rRNA processing and maturation. This protein is not detected in the residual nucleolar structures of cells inactive in rRNA synthesis such as amphibian and avian erythrocytes. During mitosis, the nucleolar material containing ribosomal protein 51 undergoes a remarkable transition and shows a distribution distinct from that of several other nucleolar proteins. In prophase, the nucleolus disintegrates and protein 51 appears in numerous small granules scattered throughout the prophase nucleus. During metaphase and anaphase, a considerable amount of this protein is found in association with the surfaces of all chromosomes and finely dispersed in the cell plasm. In telophase, protein 51-containing material reaccumulates in granular particles in the nucleoplasm of the newly formed nuclei and, finally, in the re-forming nucleoli. These observations indicate that the nucleolus-derived particles containing ribosomal protein 51 are different from cytoplasmic ribosomes and, in the living cell, are selectively recollected after mitosis into the newly formed nuclei and translocated into a specific nucleolar subcompartment, i.e ., the granular component. The nucleolar location of ribosomal protein 51 and its rearrangement du'ring mitosis is discussed in relation to the distribution of other nucleolar proteins. KW - Cytologie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39695 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Hinssen, Horst A1 - Franke, Werner W. A1 - Jockusch, Brigitte M. T1 - Microinjection of actin-binding proteins and actin antibodies demonstrates involvement of nuclear actin in transcription of lampbrush chromosomes N2 - Nuclei of amphibian oocytes contain large amounts of actin, mostly in unpolymerized or short-polymer form. When antibodies to actin or actin-binding proteins (fragmin and the actin modulator from mammalian smooth muscle) are injected into nuclei of living oocytes of Pleurodeles waltlii, transcription of the lampbrush chromosomes, but not of the rRNA genes, is inhibited. When transcription is repressed by drugs or RNA is digested by microinjection of RNAase into oocyte nuclei, an extensive meshwork of actin filament bundles is seen in association with the isolated lampbrush chromosomes. These observations indicate a close relationship between the state of nuclear actin and transcriptional activity and suggest that nuclear actin may be involved in transcriptional events concerning protein-coding genes. Y1 - 1984 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39706 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Hansmann, Paul A1 - Falk, Heinz A1 - Sitte, Peter T1 - Ultrastructural localization of DNA in two Cryptomonas species by use of a monoclonal DNA-antibody N2 - Immunogold cytochemistry - DNA localization - Cryptomonas nucleomorph The distribution and subcellular localization of DNA in the unicellular alga Cryptomonas has been investigated electron-microscopically by indirect immunocytochemistry, using a monoclonal DNA antibody and a gold-Iabeled secondary antibody. This technique proved to be very sensitive and entirely specific. DNA could be demonstrated in four different compartments (nucleus, nucleomorph, plastid, and mitochondrion). Within the plastid, DNA is concentrated in stroma regions that are localized preferentially around the center of the organelle. The mitochondrion contains several isolated DNA-containing regions (nucleoids). Within the nucleus, most of the DNA is localized in the 'condensed' chromatin. DNA was also detectable in small areas of the nucleolus, whereas the interchromatin space of the nucleus appeared almost devoid of DNA. Within the nucleomorph, DNA is distributed inhomogeneously in the matrix. DNA could furthermore be detected in restricted areas of the 'fibrillogranular body' of the nucleomorph, resembling the situation encountered in the nucleol us. The presence of DNA and its characteristic distribution in the nucleomorph provide additional, strong evidence in favour of the interpretation of that organelle as the residual nucleus of a eukaryotic endosymbiont in Cryptomonas. KW - Cytologie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39746 ER - TY - JOUR A1 - Scheer, Ulrich T1 - Changes of nucleosome frequency in nucleolar and non-nucleolar chromatin as a function of transcription: an electron microscopic study N2 - The morphology of nucleolar and non-nucleolar (Iampbrush chromosome loops) chromatin was studied in the electron microscope during states of reduced transcriptional activity in amphibian oocytes (Xenopus laevis, Triturus alpestris, T. cristatus). Reduced transcriptional activity was observed in maturing stages of oocyte development and after treatment with an inhibitor, actinomycin D. Strands of nucleolar chromatin appear smooth and thin, and contain only few, if any, nucleosomal particles in the transcribed units. This is true whether they are densely or only sparsely covered with lateral ribonucleoprotein fibrils. This smooth and non-nucleosomal character is also predominant in the interspersed, apparently nontranscribed rDNA spacer regions. During inactivation, however, nucleolar chromatin frequently and progressively assumes a beaded appearance in extended fibril-free-that is, apparently nontranscribed - regions. I n either fUll-grown 00- cytes or late after drug treatment, most of the nucleolar chromatin is no longer smooth and thin, but rather shows a beaded configuration indistinguishable from inactive non - nucleolar chromatin. In many chromatin strands, transitions of fibril-associated regions of smooth character into beaded regions wihout lateral fibrils are seen. Similarly, in the non-nucleolar chromatin of the retracting lampbrush chromosome loops, reduced transcriptional activity is correlated with a change from smooth to beaded morphology. Here, however, beaded regions are also commonly found interspersed between the more or less distant bases of the lateral fibrils, the putative transcriptional complexes. I n both sorts of chromatin, detergents (in particular Sarkosyl) that remove most of the chromatin proteins including histones from the DNA axis but leave the RNA polymerases of the transcriptional complexes attached were used to discriminate between polymerases and nucleosomal particles. The results suggest that nucleosomes are absent in heavily transcribed chromatin regions but are reformed after inactivation. In contrast to the findings with inactivated nucleolar genes, in lampbrush chromosome loops the beaded nucleosomal configuration appears to be assumed also in regions within transcriptional units that, perhaps temporarily, are not involved in transcription. Y1 - 1978 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39750 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Sommerville, J. T1 - Structural organization of nascent transcripts and hnRNA molecules in amphibian oocytes N2 - Comparisons ofrelative lengths oflampbrush loops, nascent RNP transcripts and hnRNA molecules from oocytes of amphibia with different C-values show that there is an increasing trend in loop, and transcriptional unit, length with increase in genome size but no increasing trend with respect to RN A contour length.The formation of duplex regions and circles in RNP fibrils indicates that RNA processing may occur within the nascent fibrils. The hnRNA molecules from oocytes of the various amphibia readily form intermolecular duplex structures. These complementary sequences have a low kinetic complexity and are transcribed from highly repetitive sequences distributed throughout the genome. Their possible function is considered. Y1 - 1981 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39765 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Schmidt-Zachmann, Marion S. A1 - Hügle, Barbara A1 - Franke, Werner W. T1 - Identification and localization of a novel nucleolar protein of a high molecular weight by a monoclonal antibody N2 - A monoclonal murine antibody (No-I 14) is described which reacts specifically with a polypeptide of molecular weight (M,) 180000 present in low-speed nuclear pellets from oocytes and somatic cells of Xenopus laevis and X. borealis and in isolated amplified nucleoli. Two-dimensional gel electrophoresis has revealed the acidic nature of this polypeptide (isoelectric at pH of ca 4.2 in the presence of 9.5 M urea). A relatively large proportion of the protein is extracted at elevated ionic strength( i.e., at 0.4-0.5 M alkali salt) in a form sedimenting at approx. 7-8S , compatible with a monomeric state. It is also extracted by digestion with RNase but not with DNase. In immunofluorescence microscopy, antibody No-114 stains intensely nucleoli of oocytes and all somatic cells examined , including the residual nucleolar structure of Xenopus erythrocytes which are transcriptionally inactive. During mitosis the antigen does not remain associated with the nucleolar organizer regions (NOR) of chromosomes but is released and dispersed over the cytoplasm until telophase when it re-associates with the reforming interphase nucleoli. At higher resolution the immunofluorescent region is often resolved into a number of distinct subnucleolar components of varied size and shape. Immunoelectron microscopy using colloidal gold-coupled secondary antibodies reveals that the M, 180000 protein is confined to the dense fibrillar component of the nucleolus. This conclusion is also supported by its localization in the fibrillar part of segregated nucleoli of cells treated with actinomycin D. We conclude that nucleoli contain a prominent protein of M, 180000 which contributes to the general structure of the dense fibrillar component of the interphase nucleolus , independent of its specific transcriptional activity. Y1 - 1984 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39786 ER - TY - JOUR A1 - Schüssler, Ulrich T1 - Mobilisation einzelner Elemente in Amphiboliten aus der Umgebung der KTB-Lokation, Zone Erbendorf-Vohenstrauss, nördliche Oberpfalz N2 - No abstract available KW - Mineralogie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39248 ER - TY - JOUR A1 - Thiry, Marc A1 - Scheer, Ulrich A1 - Goessens, Guy T1 - Localization of nucleolar chromatin by immunocytochemistry and in situ hybridization at the electron microscopic level N2 - Nucleoli are the morphological expression of the activity of a defined set of chromosomal segments bearing rRNA genes. The topological distribution and composition of the intranucleolar chromatin as well as the definition of nucleolar structures in which enzymes of the rDNA transcription machinery reside have been investigated in mammalian cells by various immunogold labelling approaches at the ultrastructural level. The precise intranucleolar location of rRNA genes has been further specified by electron microscopic in situ hybridization with a non-autoradiographic procedure. Our results indicate that the fibrillar centers are the sole nucleolar structures where rDNA, core histones, RNA polymerase I and DNA to po isomerase I are located together. Taking into account the potential value and limitations of immunoelectron microscopic techniques, we propose that transcription of the rRNA genes takes place within the confines of the fibrillar centers, probably close to the boundary regions to the surrounding dense fibrillar component. Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39289 ER - TY - JOUR A1 - Gessler, Manfred A1 - König, A. A1 - Arden, K. A1 - Grundy, P. A1 - Orkin, S. H. A1 - Sallan, S. A1 - Peters, C. A1 - Ruyle, S. A1 - Mandell, J. A1 - Li, F. A1 - Cavenee, W. A1 - Bruns, G. A. T1 - Infrequent mutation of the WT1 gene in 77 Wilms' Tumors N2 - Homozygous deletions in Wilms' tumor DNA have been a key step in the identification and isolation of the WTI gene. Several additional loci are also postulated to contribute to Wilms' tumor formation. To assess the frequency of WTI alterations we have analyzed the WTI locus in a panel of 77 Wilms' tumors. Eight tumors showed evidence for large deletions of several hundred or thousand kilobasepairs of DNA, some of which were also cytogenetically detected. Additional intragenic mutations were detected using more sensitive SSCP analyses to scan all 10 WTI exons. Most of these result in premature stop codons or missense mutations that inactivate the remaining WTI allele. The overall frequency of WTI alterations detected with these methods is less than 15%. While some mutations may not be detectable with the methods employed, our results suggest that direct alterations of the WTI gene are present in only a small fraction of Wilms' tumors. Thus, mutations at other Wilms' tumor loci or disturbance of interactions between these genes likely play an important role in Wilms' tumor development. KW - Wilms' tumor KW - WTI KW - Zinc finger gene KW - Tumor suppressor gene KW - Nephroblastoma KW - Deletion analysis KW - SSCP analysis KW - Mutation screening Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34308 ER - TY - JOUR A1 - Ellgring, Johann Heinrich T1 - Psychosoziale Aspekte des Morbus Parkinson N2 - No abstract available Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34052 ER - TY - JOUR A1 - König, Dorothea T1 - Materialien zu den Fragmenten des Mihanovic-Homiliars N2 - No abstract available Y1 - 1984 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38566 ER - TY - JOUR A1 - König, Dorothea T1 - Materialien zu den Fragmenten des Mihanovic-Homiliars N2 - No abstract available Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38599 ER - TY - JOUR A1 - König, Dorothea T1 - Notizen zum Wortschatz des Vatikanski Hrvatski Molitvenik N2 - No abstract available Y1 - 1974 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38740 ER - TY - JOUR A1 - König, Dorothea A1 - Aitzetmueller, Rudolf T1 - Die Slavistik an der Universität Würzburg N2 - No abstract available Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38778 ER - TY - JOUR A1 - Hee, Katrin T1 - Nicht Tabu N2 - Dieser Artikel beschreibt eine Unterrichtssequenz für den Deutschunterricht im Bereich Deutsch als Fremdsprache und richtet sich an Lernende der Niveaustufe A2. Er zeigt, wie Lernende spielerisch sowohl rezeptive Sprachkenntnisse als auch aktive Sprachbeherrschung verbessern und ihren Wortschatz erweitern können. Ein besonders wichtiges Kriterium sind dabei der Spielcharakter und die Auflockerung des Unterrichts, sowie die Möglichkeit, individuell auf die Bedürfnisse der Studenten eingehen zu können. N2 - This paper describes a teaching sequence for German as a foreign language (A2). It shows how learners can improve their receptive and active oral skills, as well as broaden their active and passive vocabulary in a playful way. The main focus is to gain knowledge in the classroom in a relaxed atmosphere, while concentrating on the students´ individual needs. KW - Wortschatz KW - Spiele im Fremdsprachenunterricht KW - Deutsch als Fremdsprache KW - Games in language teaching KW - German as a foreign language Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39075 ER - TY - JOUR A1 - Hee, Katrin T1 - Ein internationales Kochbuch N2 - In diesem Artikel wird eine Unterrichtssequenz beschrieben, die sich über einen Zeitraum von zirka 2 Wochen hinzieht und sich an Deutschlernende auf A1-Niveau richtet. Unterrichtsprojekt und Inhalt des Artikels ist ein internationales Kochbuch, das die Studenten selbst entwerfen. Das Projekt eignet sich besonders zur Binnendifferenzierung von großen Gruppen. Jedes Kapitel wird von einer Gruppe bearbeitet, so dass die Studenten je nach Fähigkeiten und Lerntempo individuell ihr Wissen anwenden und erweitern können. Der Artikel gibt einen Überblick über die einzelnen Kapitel des Kochbuches, die jeweiligen Lernziele und allgemeine didaktische Hinweise in Bezug auf das Projekt. N2 - This paper describes a teaching project which will be aimed at students of German at the A1 level, and observed over a two week period. The project deals with the conception, writing and editing of an international cookbook. The project is particularly suited to the development of individual student´s potential in large groups. Each chapter is edited by a group so that each student can apply and further develop their own individual knowledge and skills, at their own pace. The article gives an overview of each chapter of the cookbook, the respective learning objectives and general educational conventions as to the project. KW - Projektarbeit KW - Handlungsorientierung KW - Deutsch als Fremdsprache KW - German as a foreign language Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39067 ER -