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1.
Autoradiographic and cytological investigations were performed to elucidate the role of supernumerary chromosomes (E chromosomes) in the oogenesis of Wachtliella persicariae. In contrast to the compact S chromosomes, these extra chromosomes are despiralized during the entire oogenesis (Fig. 1) and synthesize RNA (Fig. 10c). As no nucleoli could be found in the oocyte nucleus, the E chromosomes are thought to produce messenger RNA. — The S chromosomes are inactive in the first period of oocyte growth and surrounded by concentric lamellate bodies (Fig. 4). After degeneration of the nurse chamber, they also despiralize and synthesize RNA. — In certain stages of oocyte development, there is a striking correspondence in the number of bundles of the E chromosomes with the haploid number of the S chromosomes (Fig. 5). These findings could be a hint to polyploidy of the supernumerary chromosomes.With financial support by the Deutsche Forschungsgemeinschaft.Herrn Professor Dr. Dr. h.c. B. Rensch zum 70. Geburtstag gewidmet.  相似文献   

2.
Summary A microfluorometric method for measuring the DNA content of chromosomes is described. The measurements were made with the MPV (microscope photometer with adjustable measuring diaphragm, E. Leitz, Wetzlar) with an incident light fluorescence illuminator of 0,05% Feulgen (pararosaniline) stained chromosomes of the cell line B 14 FAF 28 of the Chinese hamster. The variation coefficient of the measurements ranged between 4 and 11%. The measured values correlate well with DNA measurements quoted in the literature for absorption cytophotometry and length measurements for the same chromosomes.With support from the Deutsche Forschungsgemeinschaft, AZ Mu 258/3.Parts of the results reported here are submitted by Barnim Nitsch to the medical faculty of Munich in fulfilment of the requirements for the Dr. med. degree.We thank Dr. K.-R. Trott, Gesellschaft für Strahlenforschung mbH, Neuherberg, for the original cell cultures of the Chinese hamster; Dr. F. Back, Institut für Hämatologie der GSF, München, for allowing us to use the MPV; Dr. K. Moritz, Zoologisches Institut der Universität München, for carrying out the absorption measurements on the UMSP I.  相似文献   

3.
Asynchronous DNA replication of euchromatic (E) and heterochromatic (H) chromosomes and heterochromatic B chromosomes (B) were studied in the mealybug, Pseudococcus obscurus Essig (Homoptera: Coccoidea). The study was carried out on mycetocytes of adult females and on spermatocytes of mid-second instar males by employing tritiated thymidine labeling and autoradiography. In the mycetocytes the incorporation of the labeled thymidine began and ended later in the B's than in the E chromosomes. The S period was found to be about 21 hours. The DNA replication of the E chromosomes occupied about 86% of the S period and that of the B's 33%; during 18% of the mid-S period the replication of the two types of chromosomes overlapped. In the meiotic S period of the spermatocytes, the DNA of the E chromosomes started to replicate earlier than that of the H chromosomes and the B's, but the replication of the E chromosomes, the H chromosomes, and the B's overlapped. The H chromosomes completed their replication much later than the E chromosomes and slightly later than the B's.Supported by grants GB 1585 and GB 6745 to Dr. Uzi Nur from the National Science Foundation, Washington, D. C.Part of a thesis submitted to the University of Rochester in partial fulfillment of the requirements for the degree of Doctor of Philosophy.  相似文献   

4.
In the males of the olive scale insect, Parlatoria oleae (2n=8), the paternal set of chromosomes becomes heterochromatic during late cleavage or early blastula and remains so until spermatogenesis. Immediately before the onset of meiosis in the males one or more heterochromatic chromosomes disappear from each primary spermatocyte. At prophase four euchromatic and from one to three heterochromatic chromosomes are present in each cell. The disappearance of the heterochromatic chromosomes before meiosis could be due either to the dehetero-chromatization of the heterochromatic chromosomes and their subsequent pairing with their euchromatic homologues, or to the destruction of the heterochromatic chromosomes. — The alternative interpretations of spermatogenesis in P. oleae were tested by using chromosome aberrations, which had been induced in the heterochromatic set by paternal X-irradiation, as genetic markers in breeding tests of about 400 X1 males. Meiosis was examined in X1 males which showed conspicuous chromosomal rearrangements in their somatic cells. The absence of either heteromorphic chromosome pairs or multivalents at spermatogenesis and the failure of the X1 males to transmit any form of chromosome aberration induced by paternal irradiation is strong evidence that the heterochromatic chromosomes are destroyed in P. oleae. — The evolutionary relationships of the chromosome systems in the coccids are considered. Models are outlined for the derivation of a Comstockiella system involving chromosome destruction either from a lecanoid sequence or from a hypothetical Comstockiella sequence involving chromosome pairing. Problems concerning the control of chromosome destruction are discussed.From a dissertation submitted in partial fulfillment of the requirements of Doctor of Philosophy in Genetics.This work was supported by grant GB 8196 from the National Science Foundation to Dr. Spencer W. Brown, and by a National Institutes of Health Fellowship 1 F02 CA 44173-01 to the author from the National Cancer Institute.Dedicated to Dr. Sally Hughes-Schrader on the occasion of her seventy-fifth birthday.  相似文献   

5.
Zusammenfassung Menschliche Lymphocyten, die am 6., 9. und 12. Tag nach Pockenschutzimpfung kultiviert wurden, zeigten keine sicher verwertbaren Chromosomenanomalien. Nach Infektion menschlicher Lymphocytenkulturen hemmt Vaccinevirus die Mitosen und zerst?rt die Zellen in toto parallel zur Dauer der Einwirkung. Numerische und strukturelle Ver?nderungen an den Chromosomen wurden nicht beobachtet.
The influence od vaccinia viruses on human chromosomes in vitro and in vitro
Summary Contradictory views are expressed in the literature on the question as to whether viruses induce anomalies in chromosomes. Vaccinia viruses in particular are generally stated to cause chromatid and chromosome breakage in L-cells (human embryonal lung tissue). The subject of the present paper is an experimental investigation of the effect of vaccinia viruses on the chromosomes of human blood lymphocytes. In the in vivo portion of this investigation the chromosomes were examined during and after viremia subsequent to vaccination. Only two of the eight vaccinated children examined showed a larger number of chromosome breaks during viremia than unvaccinated controls. This might possibly be due to different degrees of viremia, although local and general reactions were the same. Other causes might also be sought in vivo or in vitro, such as preparation of the chromosomes, or an unnoted mycoplasma infection of the lymphocyte cultures. In the in vitro portion of this investigation, cultures of human lymphocytes were infected with vaccinia viruses at different stages of incubation. In culture the virus concentrations exhibited a rapid initial decrease, which gradually tapered off during the period of observation. No increases in virus concentration were noted. The longer the period of infection with caccinia virus, the less growth shown by the lymphocytes, and the more mitotic cells with in toto destruction of the chromosome. Anomalies in individual chromosomes were not observed any more frequently than in controls.


(Direktor: Prof. Prof. Dr. ?. Kerpel-Fronius)

(Direktor: OMR Prof. Dr. med. habil. W. Plenert)

(Direktor: Prof. Dr. G. Veres)  相似文献   

6.
A period of chromosome spiralization and contraction was observed between premeiotic interphase and leptotene in Lilium longiflorum Croft. There was variation in the extent of preleptotene spiralization and contraction of chromosomes among microsporocytes, anthers and buds. The chromosomes sometimes contracted sufficiently to be visible as separate entities. It could then be determined that the chromosomes were single and entirely separate; synapsis and crossing-over had not yet occurred. Furthermore there was no evidence of alignment or association of homologues during the preleptotene contraction period; the chromosomes appeared to be distributed at random. The chromosomes subsequently elongated into the leptotene stage. Wherever they were visible separately the chromosomes were single in early leptotene. These observations support the classical view that synapsis of homologous chromosomes takes place during zygotene, followed by crossing-over at pachytene.It is a pleasure to dedicate this paper to Dr. Sally Hughes-Schrader on the occasion of her seventy-fifth birthday.  相似文献   

7.
Native highly repetitive DNA sequences have been allowed to react in situ with DNA-depleted polytene chromosomes of chironomids in cytological preparations. The double-stranded DNA can bind specifically to the centromeric heterochromatin, where these sequences have been localized previously by in situ hybridization. Various control experiments support the conception that heterochromatin-specific DNA-binding proteins are involved in the in situ binding. Dedicated to Prof. Dr. Wolfgang Beermann for his 60th birthday  相似文献   

8.
Surface-spread polytene (SSP) chromosomes of salivary glands from late third-instar larvae were used for the construction of an electron microscopic (EM) photo map of the entire genome of D. hydei. In comparison with the light microscopic chromosome map of Berendes (1963), based on squash preparations, the EM micrographs depict some 40%–50% more bands. — Two different types of chromosome constrictions are described. One type is assumed to be caused by differential distribution of chromosomal proteins; the other one appears to represent underreplicated sections in the salivary gland chromosomes.Dedicated to Prof. Dr. H.J. Becker on the occasion of his 60th birthday  相似文献   

9.
High resolution patterns of DNA replication in human lymphocyte chromosomes during early and late S-phases were studied by means of the BrdU-Hoechst-Giemsa technique. The late replicating bands were found to be identical with highly detailed G-bands. Between early replicating bands and R-bands subtile differences were observed. A possible correlation between a replication band seen on the chromosomal level and a replication cluster observed after fiber autoradiography is discussed. Dedicated to Professor Dr. Wolfgang Beermann on the occasion of his 60th birthday  相似文献   

10.
Summary The chromosome complement of two ovine (Ovis aries L.) kidney cell lines are described. Nuclei of MDOK, the older cell line, are generally larger than those of OK cells, they are hypo-tetraploid and show considerable chromosomal irregularities both in structure and behavior. The OK line observed since its initiation, is now hyper-diploid and exhibits a gradual accumulation of chromosomes. Both cell lines have in common the fact that they now maintain a larger proportion of chromosomes with interstitial centromeres than telocentric chromosomes. This observation parallels similar ones made earlier in bovine cells. However, the processes whereby this condition arose in the respective cultures are believed to be different and are discussed.Dedicated to Professor Dr. H. Bauer on the occasion of his 60th birthday.Supported in part by Contract No. PH 43-63-13 from the National Cancer Institute, National Institutes of Health, Public Health Service.  相似文献   

11.
Two cases of chronic myelogenous leukaemia were studied during the final blastic crisis. The results show in case I a stemline of 50 (2 Ph1) intact and 2 fragmentary chromosomes, with a considerable variation from this mode, and in case II a stemline of 48 chromosomes (2 Ph1), with only a slight variation. Different aspects of the presentation of aneuploidy in CML are discussed in relation to the findings in both cases, and special attention is given to the formation of stemlines.Director: Prof. Dr. H. Baitsch  相似文献   

12.
The nuclei of the growing oocytes of Sepia officinalis contain lamp-brush chromosomes with clearly demonstrable chromomeres bearing pairs of lateral loops (Fig. 4). Similar to the findings of Callan and Lloyd (1960) in amphibian oocytes the chromosomes of Sepia exhibit some specially organized loops which can be used as landmarkers for recognizing certain chromosomes (Fig. 5). Maximal loop despiralization occurs only in nuclei of follicles during their initial growth phase. The following developmental period is characterized by a successive contraction of loops and chromosome axes (Fig. 7), despite the fact that the diameter of the oocyte nucleus enlarges still three times. In the oldest nuclei hundreds of nucleolus-like granules arise near the chromosomes which later spread over the entire nucleus (Fig. 9).

Herrn Professor Dr. K. Bier () in dankbarer Verehrung gewidmet.  相似文献   

13.
Mutant genes affecting higher plant meiosis   总被引:13,自引:0,他引:13  
Summary That meiosis is conditioned by a large number of genes majority of which are present in a dominant state, is evidenced by the detection of numerous monogenic recessive mutant genes which affect the premeiotic, meiotic and post-meiotic course of events. These genes are site- and stage-specific, and a few are sex specific. Of these, the most prevalent are the mutant genes affecting male meiosis and causing male sterility (ms genes) and those inhibiting synapsis and chiasma formation (synaptic genes) and leading to gametic sterility. Majority of the mutant genes affect the entire chromosomal complement but a few influence only specific chromosomes of a complement so that the chromosomes behave differentially within a genome of the same species. Some mutant genes alter chromosome form and function, others modify integrity, degree of spiralization, movement and migration of chromosomes. Their cytogenetic behaviour, genetic significance and breeding utility are described and discussed.Dedicated to Professor Dr. Werner Gottschalk, Director, Institute of Genetics, University of Bonn, Federal Republic of Germany, on his 65th birthday for his excellent scientific contribution and humane nature  相似文献   

14.
Summary Karyotypes of 6 patients with chronic lymphatic leukaemia were examined (lymphocytes). Chromosomes of one patient showed abnormality in the form of a structural mosaicism concerning the E group. Karyotype analysis showed in 70 p.c. of metaphases an unusual chromosome in the E group, morphologically very similar to C group chromosomes.(Director: Prof. Dr. med. M. Kedra)  相似文献   

15.
The replication pattern of the X and Y chromosomes at the beginning of the synthetic phase was studied in human lymphocyte cultures partially synchronized by the addition of 5-fluoro-2-deoxyuridine (FUdR). The data were evaluated statistically by an analysis of the distribution of silver grain counts over the X and Y chromosomes. —In cells from normal females, one of the X chromosomes began replication later than any other chromosomes of the complement. The short arm of the late replicating X chromosome started replication earlier than the long arm. The telomeric region of the short arm was a preferential site of DNA synthesis at the beginning of replication. —In partially synchronized lymphocyte cultures from a patient with the XXY syndrome, the Y chromosome started replication together with the late replicating X chromosome. The Y chromosome most frequently replicated synchronously with the short arm of the X. The centromeric region of the Y chromosome initiated synthesis before the telomeric region and appeared to replicate synchronously with the telomeric region of the short arm of the X. These findings are discussed with reference to the pairing of the X and Y chromosomes at meiosis.Supported in part by the National Institute of Health Research Grant HD-01979 and National Foundation Birth Defects Research Grant CRCS-40. Dr. Knight was a predoctoral fellow under National Institute of Health Training Program HD-00049-09.  相似文献   

16.
Summary Isolated protoplasts of Vicia faba and Petunia hybrida have been fused by the action of Ca++, high pH and, occasionally, PEG. The heterokaryotic stage frequently endured mitotic divisions. Only one cell was found with apparently fusing nuclei. Another heterokaryon showed asynchronous phases in the nuclear cycle. Three hybrid tissues have been identified 50 and 60 days after fusion. One of them could be propagated, is 9 months old and still rapidly proliferating. The fusion hybrids contained predominantly nuclei or chromosomes of one or the other species and a few chromosomes of the second parent. These observations were assigned to chromosome elimination which has been conclusively seen in cells containing nuclei of Petunia-type and one or two chromosomes of Vicia left in the cytoplasm. Breakage of chromosomes was the only type of chromosome mutations found in hybrid tissue.Dedicated with compliments to Professor Dr. Josef Straub on the occasion of his 67th birthday and the 17th anniversary of his directorship within the 50 years of history of the Erwin-Baur-Institut (Max-Planck-Institut für Züchtungsforschung)  相似文献   

17.
Summary Cytogenetic studies of an 8-year-old caucasian girl with typical but mild manifestation of Bloom's syndrome showed a characteristic increase of homologous chromatid translocations and prematurely condensed chromosomes. The average frequency of sister chromatid exchanges (SCE) in lymphocytes with 133 was much higher than in skin fibroblasts with 49. The inter- and intrachromosomal distributions of SCE in lymphocytes were analyzed.Prof. Dr. H.-R. Wiedemann to his 60th birthday.  相似文献   

18.
A system of nomenclature for band patterns of mouse chromosomes   总被引:40,自引:0,他引:40  
Mouse chromosomes banded by quinacrine mustard staining, by the ASG technique, or by Giemsa staining following trypsinization or chymotrypsinization are described in detail. Three hundred and twelve regions within the mouse karyotype can be distinguished and a simple system of nomenclature is proposed for naming these regions. This nomenclature is applied to discussion of the locations of the breakpoints of twenty translocations and of many specific gene loci.Dedicated to the memory of Dr. Stanley W. Wright, in gratitude for his support of, and interest in, our work.Supported by Cancer Research Funds of the University of California and USPHS Grant HD 04608.  相似文献   

19.
Summary Meiotic studies of a boy, both of whose sibs also had Down's syndrome, were suggestive of a 21/21 chromosome rearrangement. Banding of somatic chromosomes from his mother and affected sister validated this interpredation and indicated a 21/21 translocation, not an isochromosome.
Zusammenfassung Meiose-Untersuchungen an einem Jungen, dessen beide Geschwister ebenfalls das Down-Syndrom hatten, ließen ein 21/21-Chromosomen-Rearrangement vermuten. Die Bandenmuster somatischer Chromosomen seiner Mutter und seiner ebenfalls kranken Schwester sprachen für diese Interpretation und wiesen auf eine 21/21-Translokation, nicht auf ein Isochromosom hin.


These studies were supported by NIH Grants AM No. 13173 and HD No. 05082 (Dr. Hecht) and RR-62 and No. 5 SO 1 RR054-11 (Dr. Seely).  相似文献   

20.
Bender  K.  Burckhardt  Klara 《Human genetics》1970,9(1):75-85
Summary Chromosome aberrations permit the assignment to and the exclusion of genes on certain chromosomes or definite segments. Only exclusion methods are discussed. All relevant data are compiled in a table from which it can be determined, which genetic systems are excluded from certain autosomal segments.
Zusammenfassung Angeborene Chromosomenaberrationen ermöglichen die Zuordnung und den Ausschluß von Genen auf dem betroffenen Segment. Nur die für Lokalisierungsausschlüsse verwendbaren Methoden werden diskutiert. Aus einer Zusammenstellung der bisherigen Befunde wird ermittelt, welche genetischen Systeme von einer Lokalisierung auf bestimmten Autosomen(segmenten) des Menschen ausgeschlossen werden können.


Direktor: Prof. Dr. Dr. H. Baitsch

Supported by the Deutsche Forschungsgemeinschaft.  相似文献   

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