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1.
Induced chromosome aberrations in unfertilized oocytes of mice   总被引:1,自引:0,他引:1  
Summary Just before ovulation we treated 10–12-week-old female mice of the strains C3H and (101×C3H)F1 with 2.3.5.-triethyleneimonobenzoquinone-1.4 (T), cyclophosphamide (C) and methotrexat (M). The chromosome analysis took place shortly after ovulation at the time of metaphase II. The method described in detail seems to be appropriate to examine the induction of genetic defects during oogenesis by chemical agents.
Zusammenfassung Wir behandelten 10–12 Wochen alte weibliche Mäuse der Stämme C3H und (101×C3H)F1 kurz vor der Ovulation mit 2.3.5.-Triethyleniminobenzochinon-1.4 (T), Cyclophosphamid (C) und Methotrexat (M) Die Chromosomenanalyse erfolgte kurz nach der Ovulation zum Zeitpunkt der Metaphase II. Die im Detail beschriebene Methode erscheint geeignet, die Auslösung genetisch bedingter Eireifungsstörugen durch chemische Agentien zu untersuchen.


This work was sponsored by the Deutsche Forschungsgemeinschaft.  相似文献   

2.
Metaphase chromosomes of Mesostoma ehrenbergi and M. lingua when swollen attain sizes many times their normal one and form ramifications if they are treated with nuclear isolation medium or destilled water. After spreading and pronase digestion it can be demonstrated that the ramifications and ribbon like structures are formed by chromosomal protein and that they are partly free of chromosomal fibers. The chromosomal fibers (DNA and rest of protein) with a diameter of about 150 Å are composed of two sub-units about 70 Å in diameter. Any one subunit can be reduced to a single DNA containing strand of 30 Å by pronase digestion. The double strandedness is confirmed by chromatid isolabeling in 3H-thymidine-autoradiographs.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

3.
Summary A simple, yet rapid and accurate apparatus for cytophotometry is described. It employs rapid scanning of an object field of 9 × 9 µ with a light spot of 0.8 µ in diameter. Light source variations are canceled through a two-beam arrangement. Silicon diodes are used as logarithmic elements and a sensitive galvanometer acts as an integrating measuring device.
Zusammenfassung Es wird ein einfacher Zytophotometer für schnelle und präzise Messungen im sichtbaren Licht beschrieben. Ein mikroskopisches Feld (9 × 9 µ) wird von einem Leuchtpunkt (Durchmesser 0,8 µ) abgerastert. Helligkeitsschwankungen der Lichtquelle werden durch ein Zweistrahlverfahren kompensiert. Siliciumdioden finden Verwendung als logarithmische Schaltelemente und die integrierte Extinktion wird von einem empfindlichen Galvanometer direkt angezeigt.


With 5 Figures in the Text  相似文献   

4.
    
Summary Before x-raying young pupae ofEphestia kühniella were treated for 6 hours with low (–7o, +3°C) or high (+30o, +35o, +40°C) temperatures. The mutation rates of four types of scale mutations (somatic mutations) were influenced by these temperature treatments in a different manner. In consequence there were different mutation spectra at the applied temperatures. The relation of mutation ES 1 to mutation ES 2 was 5:1 in the –7°C group and 11:1 in the +35°C group. The differences are statistically significant.

Mit 1 Textabbildung

Die Untersuchung wurde vom Bundesministerium für Atomkernenergie und Wasserwwirtschaft unterstützt.  相似文献   

5.
Summary No recombination could be observedwithin three extended mutations (block mutations) of the rII region of phage T4. The block mutations are studied under two different conditions, where (1) both parental particles contained an identical block mutation, and where (2) a block mutation was present in only one parent, while the other contained a point mutation, or was wild type at the corresponding location.In further experiments it was shown that the presence of a block mutation in only one parent reduces recombinationoutside the block. This interference decreases with increasing distance between the block mutation and the other sides.Although up to now no difference in density could be observed between wild type particles and block mutants, the genetic data which are reported here do support the interpretation that block mutations represent deletions within the genetic material.

Mit 3 Textabbildungen

Dissertation an der Mathematisch-Naturwissenschaftlichen Fakultät der Universität zu Köln, eingereicht im Januar 1962.  相似文献   

6.
    
Summary Experiments were carried out to investigate the effects of different wavelengths of X-rays (10–100 kV, 600 r) on four somatic mutations of the scales on the hind wings of Ephestia kühniella Z.We made three experiments at different times. Each consisted of eight groups for the different voltages of the X-rays.The mutation rates and the relative frequencies of the four mutations were compared.There are no correlations between the mutational spectrum and the qualities of X-rays.The variations between each group of one experiment and between the three experiments are great. It cannot be said which factors may be responsible for this variability.

Mit 2 Textabbildungen

Die Untersuchung wurde im Auftrag des Sonderausschusses Radioaktivität durchgeführt und vom Ministerium für Atomkernenergie und Wasserwirtschaft unterstützt.  相似文献   

7.
Zusammenfassung Es wird eine Übersicht über die verschiedenen Methoden zur DNS-Messung an Chromosomen gegeben. Die Methoden werden kurz beschrieben und die wichtigsten Ergebnisse der verschiedenen Autoren diskutiert.
Problems of characterizing individual chromosomes by measuring the DNA content
Summary A review of the different methods of determining the DNA content of individual chromosomes is given. The methods are described briefly, and the results of the different authors are discussed.


Nach einem Referat anläßlich der 11. Tagung der Gesellschaft für Anthropologie und Humangenetik, Mainz, 7. 10. 1969.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft, AZ Mu 258/3.  相似文献   

8.
Ohne Zusammenfassung

Mit 1 Textabbildung

Erschienen in Histochemie2, 298–305 (1961)  相似文献   

9.
Zusammenfassung Nach Hemmung der de novo-Synthese von TMP durch 5-F-UdR läuft die DNS-Synthese in vitro in Anwesenheit von 10–5 M/l mit unveränderter Geschwindigkeit ab. Dadurch ist die DNS-Synthese-Dauer über die quantitative autoradiographische Messung des 14C-TdR-Einbaus bestimmbar. Diese in vitro-Methode wird an Rattenknochenmark und Zellen einer CML geprüft. Erste Ergebnisse zeigen eine gute Übereinstimmung mit in vivo-Messungen durch andere Methoden.
In vitro determination of the duration of DNA synthesis of individual cells
Summary Suspended haemopoietic cells are incubated in the presence of 5-fluoro-deoxyuridine (5-F-UdR) as an inhibitor of the de novo synthesis of thymidine monophosphate (TMP). The DNA synthesis rate remains undisturbed, if 10–5 M/l thymidine (TdR) is added. Thus, the DNA synthesis rate of individual cells can be determined by means of a quantitative autoradiographic method in measuring the incorporation rate of 14C-TdR into the DNA of the cells. DNA synthesis rates are then converted into DNA synthesis times. This in vitro method has been checked in cells of rat bone marrow and of peripheral blood in a case of chronic myelocytic leukaemia (CML). Preliminary results correlate well with in vivo estimations obtained by other methods.


Studie im Rahmen des Assoziationsvertrages EURATOM-GSF für Hämatologie Nr. 031 641 BIAD

Unterstützt durch die Deutsche Forschungsgemeinschaft: SFB 51/5  相似文献   

10.
Zusammenfassung Die vonVaurie (1950) mitParus rubidiventris vereinigte ArtP. rufonuchalis wird revalidiert. Die ausschlaggebenden Hinweise sind sympatrisches Sommervorkommen, Paarbildung nur zwischen äußerlich gleichen Individuen und deren sehr unterschiedlicher Reviergesang.
Species status ofParus rufonuchalis Blyth
Summary The speciesParus rufonuchalis, lumped byVaurie (1950) withP. rubidiventris is revalidated. The striking hints are sympatric summer occurrence, pairs consisting only of specimens of the same outer appearence and their very different songs.


Herrn Professor Dr. E. Schüz zum 70. Geburtstag gewidmet.

Mit einem Jahresstipendium des DAAD und einer Sachbeihilfe der DFG — Ergebnisse der Nepal-Reise 1969/70, Nrs. 3. — Nr. 2: Z. Arbeitsgem. österr. Ent. (Wien), 23 (1): 15–24, 1971.  相似文献   

11.
Résumé Les auteurs, étudiant les diverses cellules épithéliales rencontrées dans la région périportale du foie foetal humain, décrivent deux types d'éléments qui possèdent des caractères ultrastructuraux intermédiaires entre ceux de la cellule épithéliale biliaire et ceux de l'hépatocyte.Ils décrivent un type cellulaire à cytoplasme et noyau fortement denses, différents de ceux que l'on observe dans les «dark cells» de Steiner et coll. (1962b).
Summary The fine structure of the different cells at the margin of the portal spaces was investigated in the foetal human liver. Two types of cells intermediate between biliary epithelial and parenchymal elements were described.In addition, a type of cell in which both the cytoplasm and nucleus are electron-dense was observed. This element is different from the dark cell of Steiner et al. (1962b).


Travail subventionné par le «Fonds National Suisse de la Recherche Scientifique», requête N 3731.

Avec la collaboration technique de Mme M. Schreyer et de Mlle M.-M. Bertholet.  相似文献   

12.
Résumé A pH 5,57, en modifiant les durées de fixation et d'incubation, il est possible d'appliquer la technique de coloration histochimique des plaques motrices de Koelle et Friedenwald à des muscles ou à des prélèvements tissulaires d'épaisseur allant jusqu' à 3 mm.Cette technique nous a permis de repérer, chez le Chat, la situation des jonctions neuro-musculaires des muscles intercostaux par rapport aux arcs chondro-costaux. La topographie des plaques motrices du diapragme a été également précisée.
Summary At pH 5.57, with modifications of the times of fixation and incubation, it is possible to apply the Koelle and Friedenwald histo-chemical technique to muscles or samples of tissues 3 mm thick. This technique allows to study, in the cat, the localization of end-plates in the intercostal space. The topography of the diaphragmatic end-plates has been studied.


Attaché de recherche à l'I.N.S.E.R.M.

Nous remercions Mme. A. Rousseau pour sa collaboration efficace lors de la phase initiale de ce travail.  相似文献   

13.
Zusammenfassung Ein tagesperiodischer Wechsel der spektralen Zusammensetzung des Lichtes (12 Std 2900 ° K:12 Std 3400 ° K) vermag die Bewegungsaktivität vonTaeniopygia guttata zu synchronisieren, selbst wenn die meßbare Lichtintensität konstant bleibt (100 Lux, 440 erg × cm–2 × sec–1). Die spektrale Zusammensetzung des Lichtes ist von der Sonnenhöhe abhängig. Dieser Faktor kann als tagesperiodischer Zeitgeber in der Hocharktis wirksam sein.
Quality of light is a Zeitgeber forTaeniopygia guttata
Summary Circadian locomotor activity ofTaeniopygia guttata was synchronized by changing spectral distribution of light (12 h 2900 ° K: 12 h 3400 ° K). Intensities were equal in both phases (100 Lux, 440 erg. cm–2. sec–1). Light quality depends on the altitude of the sun and, therefore, it might be a Zeitgeber in high arctic regions.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft (Sachbeihilfe an Prof. Remmert Be 107/12).  相似文献   

14.
Toxicity or resistance tests on the green peach aphid Myzus persicae (Sulz.) by incorporating the toxicant into artificial media are influenced by a number of factors. It was found that the morph of the aphid had a pronounced effect on results. Apteriform larvae imbibed more food and at the discriminatory concentration tested were also over five times more susceptible to phosphamidon than were alatiform larvae. No difference was observed between the two aphid morphs in the inhibition of their AChE by malaoxon.
Résumé Le milieu artificiel d'élevage utilisé est celui de Dadd et al. (1967). Les insecticides adjoints à ce milieu sont le phosphamidon et le malaoxon. Il se révèle que des larves «aptériformes» prennent plus de nourriture que les larves «alatiformes», et sont au moins cinq fois plus sensibles que ces dernières à une concentration donnée d'insecticide. Cependant le taux d'inhibition de l'acetylcholinestérase est sensiblement le même chez ces deux formes.


Hemiptera, Aphididae.

This research has been financed in part by a grant made by the U.S. Department of Agriculture, under PL 480.  相似文献   

15.
Summary We deal with a new variety ofAspergillus which we callAspergillus gracilis Bainiervar. sartoryi (Biourge) Batista, Lima and Vital.This variety appears to be very important under the phylogenetic point of view, apparently being an intermediate form betweenAspergillus andPenicillium.Its morphology resemblesA. gracilis but the conidia characteristics are distinct; we took the epithetsartoryi fromA. sartoryi Biourge which was not described by the respective author.We suggest, too, the transfer of the seriesA. restrictus, where we put our new variety, from the groupA. glaucus, to become independant, as a connective series in the phylogenetic development betweenAspergillus andPenicillium, since the type of the series and the other elements that it embraces does not produce sclerotia or cleistothecia and the conidial apparatus offers curious similarity toPenicillium. Besides, some fungi of the series grow well in certain culture media, in complete discordance with the members of the groupA. glaucus.

Publiçacão no 4

Chefe do Instituto de Micologia;

Diretor do Instituto de Antibióticos e Prof. de Microbiologia da Escola de Química;

Assistente micologista do Instituto de Micologia — (Todos da Universidade do Recife).

Os autores declinam o seu agradecimento ao Dr.Heraldo da Silva maia, Assistente micologista eD. Marilene Maranhão Moreira, Auxiliar-Técnico, do Instituto de Micologia, pela colaboração que lhes prestaram, durante a realização do presente trabalho.  相似文献   

16.
Zusammenfassung Das Papillon-Léage-Psaume-(Oro-facio-digitales-)Syndrom und das Mohr-Syndrom sind genetisch eigenständige und auch klinisch unterscheidbare Symptomenkomplexe. Einige Patienten, die früher als dem Papillon-Léage-Psaume-Syndrom zugehörig betrachtet wurden, müssen auf Grund heutiger Kenntnis dem Mohr-Syndrom zugeordnet werden. Die differentialdiagnostisch entscheidenden Gesichtspunkte werden diskutiert und zusammengestellt. Ein von Helbig (1958) und ein von Koberg u. Schettler (1966) beschriebener Patient gehören möglicherweise einem anderen, selbständigen Fehlbildungskomplex an.
Differential diagnosis between Papillon-Léage-Psaume-Syndrome and Mohr-Syndrome
Summary The oro-digito-facial syndrome (Papillon-Léage-Psaume) and the Mohr-Syndrome are genetically seperate entities and can be distinguished clinically. Several patients previously thought to belong to the Papillon-Léage-Psaume Syndrome can now be diagnosed to represent cases of the Mohr-Syndrome. The differentialdiagnosis is discussed. A case described by Helbig (1958) and a case published by Koberg and Schettler (1966) may represent another related type of malformation.


Direktor: Prof. Dr. Dr. R. Ritter

Nach einem Vortrag, gehalten anläßlich der Tagung der Arbeitsgemeinschaft für Kieferchirurgie in Bad Homburg v. d. Höhe am 17. 5. 1969.

Herrn Prof. Dr. Dr. h. c. Hans Nachtsheim zum 80. Geburtstag gewidmet  相似文献   

17.
Summary The mutagenic activity of the tri-functional ethyleneimino derivate Trenimon® (2,3,5-tri-ethyleneimino-benzoquinone 1,4) was tested in very low concentrations on human lymphocytes.The investigations revealed that a concentration of 2.8×10-10 Mol/l or higher caused a marked dose-dependent increase of all types of aberrations. In concentrations less than 2.8×10-10 Mol/l, the amount of aberrant cells as well as the rates of gaps and breaks per metaphase lay in the same range as for the blank control, as indicated by statistical treatment of the results.
Zusammenfassung Bestimmung der Schwellendosis der cytogenetischen Wirkung von Trenimon® an menschlichen Lymphocyten in vitro.Die cytogenetische Aktivität des trifunktionellen Äthyleniminderivates Trenimon® (2,3,5-Tris-äthylenimino-benzochinon 1,4) in sehr niedrigen Konzentrationsbereichen wurde an menschlichen Lymphocytenkulturen geprüft.Die Versuche ergaben daß von der Konzentration 2,8×10-10 Mol/l an ein steiler Anstieg aller Aberrationstypen mit der Dosiserhöhung zu verzeichnen ist. In den Konzentrations-bereichen unter 2,8×10-10 Mol/l lagen die Anzahl aberranter Zellen sowie die Achromasie-und Bruchraten pro Metaphase im, Bereich der Nullkontrolle.Der experimentell ermittelte Schwellenwert der cytogenetischen Aktivität von Trenimon wurde durch die statistischen Teste erhärtet.


This investigation comprises the results of a work pressented for a diploma by W. Kaufmann  相似文献   

18.
Günter Fellenberg 《Planta》1965,64(3):287-290
Summary Bromouracil and histone inhibit root formation and tissue differentiation in dark grown pea epicotyls when they are applicated 11–48 hours after culture initiation. The activity of cell division is thereby not suppressed.

Mit 3 Textabildungen  相似文献   

19.
    
Summary The mutagenicity of seven N-alkylnitrosamides was investigated in backmutation tests inSaccharomyces cervisiae (ad6–45). Dose-response curves were run for each substance. Three types of curves were observed: linear, plateau and a type showing a sharp peak followed by a gradual increase (maximum-minimum-type), as described previously. There is a possibility that the first two types are in fact a modification of the third. The simplest interpretation of this third type could be the existence of two populations of different sensitivity in our strain. A comparison between the mutagenic threshold doses of the various nitrosamides and the rate of their decomposition by hydrolysis in vitro does not show any correlation.

Mit 9 Textabbildungen  相似文献   

20.
Summary By making a tongue-slit in the shaft of the inflorescence ofArabidopsis thaliana 7 different urethanes (1/200 mol+1/200 mol KCl) were forced into the buds through the transpiration stream. After this treatment with 6 of these substances the frequency of the monohybrid segregating mutations was significantly raised 5- to 10times over the control as determined by seedling tests.The mutation frequency was positively correlated with the size of the urethan molecule and seemed to be little affected by its chemical substitution. The mutants were of the same type than those obtained after irradiation with X-rays.These results are in agreement with the conception that the mutagenic effect of the urethanes is indirect and probably due to general disturbances of different metabolic processes in the cell.

Mit 2 Textabbildungen  相似文献   

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