Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Cytogenetic investigations on development and degeneration of oocytes from juvenile mice (1980)
    Springer
    Anatomy and embryology 161 (1980), S. 9-18 
    Details
    ISSN: 1432-0568
    Keywords: Cytogenetics ; Oocytes ; Development ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Oocytes were isolated by mechanical disruption of the ovarian tissue of juvenile mice aged between 8 and 28 days p.p. Different types of oocytes could be distinguished by direct observation using an inverted light microscope. Their relative amount within the oocyte population isolated was determined in relation to age of the animals. The following types were isolated and examined: 1. “Normal” oocytes containing an intact germinal vesicle (that is, a nucleus in dictyate stage). In all age groups 55 to 83% of the oocytes were of this type. Their nuclear developmental stage was determined by studying their capacity to resume meiosis in culture as a function of age. 45% of the oocytes isolated from 15 day old mice were competent to resume meiosis. In mice aged 21 days more than 80% of the oocytes measuring about 80 μm in diameter resumed meiosis in vitro. No further increase in mean diameter or in the amount of competent oocytes could be found in older mice. 2. Degenerating oocytes. Five different types could be distinguished. a) “Atretic” oocytes present in all age groups investigated with pyknotic or disintegrating nuclei; b) “Precociously matured” oocytes first observed in mice aged 15 days containing normal diakinesis-and metaphase II-chromosomes; c) “Vacuolized” oocytes first isolated on day 18 having metaphase II-chromosomes scattered within the cytoplasm; d) “Fragmented” oocytes also first observed 18 days p.p. containing chromatin dissociated into micronuclei of different sizes within the cytoplasmic fragements; e) “Ghost” oocytes present in all age groups, characterized by the disintegration of the cytoplasm so that only the surrounding zona pellucida can be clearly seen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304665
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Surface characteristics of oocytes from juvenile mice as observed in the scanning electron microscope (1980)
    Springer
    Anatomy and embryology 161 (1980), S. 19-27 
    Details
    ISSN: 1432-0568
    Keywords: Surface characteristics ; Oocytes ; Mouse ; Scanning Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The in vivo and in vitro development of the zona pellucida as well as the vitelline membrane surface of oocytes isolated from juvenile mice aged between 8 and 30 days p.p. were investigated by scanning electron microscopy. In vivo a consistent development of the zona pellucida surface can be observed, namely the formation of a fibrous network like structure interspersed with numerous pores. After enzymatic removal of the zona pellucida the surface of the vitelline membrane was studied. In “normal” oocytes with intact germinal vesicles, microvilli were distributed over the entire oocyte surface in all age groups investigated. After resumption of meiosis in vitro a characteristic differentiation on the vitelline membrane occurs. A glabrous polar region appears in primary oocytes and a glabrous polar body in secondary oocytes. The same differentiation in surface organization could be observed in the in vivo precociously matured oocytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00304666
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Human gene therapy: possibilities and limitations (1987)
    Springer
    Cellular and molecular life sciences 43 (1987), S. 375-378 
    Details
    ISSN: 1420-9071
    Keywords: Human gene therapy ; medical and ethical issues ; hereditary diseases ; gene transfer systems ; in vitro fertilization ; embryo transfer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Gene therapy provides new options for medicine, and implies new responsibilities for making decisions relating to the limitations which reason and morality impose upon manipulation of the human genome for the benefit both of patients and of society. This contribution outlines the possibilities and limits of gene therapy in man from a medico-technical viewpoint.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01940416
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Thymine dimer repair in fibroblasts of patients with dysplastic naevus syndrome (DNS) (1988)
    Springer
    Cellular and molecular life sciences 44 (1988), S. 169-171 
    Details
    ISSN: 1420-9071
    Keywords: Dysplastic naevus syndrome ; DNA-repair ; cancer genes ; familial malignant melanoma ; monoclonal antibodies specific for UV-dimers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Dysplastic naevus syndrome (DNS) is frequently observed in association with familial melanoma and xeroderma pigmentosum (XP), but the role of UV-light in the development of DNS has not been elucidated. Previous work has shown that UV-induced unscheduled DNA synthesis is associated with the early loss of antigenicity observed in immunoassays using a monoclonal antibody specific for thymine-thymine dimers. We now show that the rate of loss of antigenicity, which reflects the relative amount of bound antibody, observed during the first 60 min following 10 Jm−2 UVC irradiation is significantly reduced (p=0.02) in cultures of fibroblasts from 7 out of 8 DNS patients compared with the results from cells of a group of 30 healthy volunteers. This observation suggests an early event in excision repair is altered in the majority of DNS patients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01952205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Chromosomes of two species of woodpeckers (Aves: Piciformes) (1983)
    Springer
    Cellular and molecular life sciences 39 (1983), S. 201-202 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The karyotypes ofDendrocopos major andD. medius show a gradual transition from macro- to microchromosomes and a high diploid chromosome number. The Z-chromosome is the largest element.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01958899
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Mating behavior and cytogenetical aspects of sex-inversion in the fishCoris julis L. (Labridae, Teleostii) (1982)
    Springer
    Cellular and molecular life sciences 38 (1982), S. 809-811 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary It was observed that in the fishCoris julis L., in its natural environment, both primary and secondary males take part in reproduction. Chromosome studies showed 23 homologous chromosome pairs, which are identical in males and females, and a variable 24th pair. The heteromorphism of this pair is identical in secondary males and in the majority of females; these are presumably the females that can undergo sex inversion. Primary males show a different heteromorphism of the same pair.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01972285
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Human in vitro fertilization and embryo transfer: expectations and concerns (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 1515-1517 
    Details
    ISSN: 1420-9071
    Keywords: Human IVF-ET ; human sterility ; bioethics ; medical issues ; legislation ; research
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01964787
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Chromosomes and human neoplasms (1976)
    Springer
    European journal of pediatrics 123 (1976), S. 1-13 
    Details
    ISSN: 1432-1076
    Keywords: Cancer etiology ; Tumor cytogenetics ; Chromosome instability syndromes ; Chromosomal syndromes ; Leukemias ; Chromosome investigations in leukemia ; Y chromosome ; Individuals at high risk of cancer ; Acquired chromosome damage ; Chromosome banding techniques
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Numerical and structural chromosome aberrations are frequently found in neoplastic cells. As demonstrated by the new chromosome banding techniques these aberrations are not random, but tend to show a specific occurrence. A model example is the leukemias where many cytogenetical investigations have been done to date. In leukemia chromosome analysis serves the following purposes: to identify a neoplastic process, to confirm and strengthen the hematological diagnosis, for the early diagnosis of transformation from a chronic leukemia into its blastic phase and for following up the clonal evolution of a leukemic cell line. In the discussion of chromosomes and neoplasms it must be mentioned that individuals demonstrating chromosomal instability and some trisomic patients show a greater tendency toward the development of a malignancy. Malignancy is primarily a cellular phenomenon caused by a disturbance in cellular regulation, whose fine events are not known. Therefore the exact role of the chromosomes in neoplastic processes cannot be stated. From experimental investigations it appears that the affected chromosomes carry cell growth regulating factors and also that a specific aberration is the result of the action of a specific agent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00497675
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Genetic analysis of familial erythrophagocytic lymphohistiocytosis (1984)
    Springer
    European journal of pediatrics 142 (1984), S. 248-252 
    Details
    ISSN: 1432-1076
    Keywords: Familial erythrophagocytic lymphohistiocytosis ; Genetic analysis ; Consanguinity rate ; Autosomal recessive inheritance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A family with two patients suffering from familial erythrophagocytic lymphohistiocytosis (FEL) is described. Reports on FEL found in the literature were collected and the family trees reconstructed. Genetic analysis of this material indicated that FEL is an autosomal recessive hereditary disease. This conclusion is supported by the following evidence: considerably increased consanguinity rate; complete concordance in monozygotic twins; more frequent occurrence in inbred populations and in cousins; limitation of cases to one generation, and results of segregation analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00540245
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Variations in karyotypes of normal premature babies, new-born babies and infants (1971)
    Springer
    Human genetics 〈Berlin〉 14 (1971), S. 33-43 
    Details
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 4754 Lymphocytenmetaphasen von 36 männlichen und weiblichen Frühgeborenen, Neugeborenen und Kleinkindern wurden nach dem Vorkommen von numerischen und strukturellen Aberrationen, von Assoziationen und sichtbaren Satelliten der akrozentrischen Chromosomen untersucht, wobei wir die Zellkulturen, die wir nach einer Mikromethode nach Hirschhorn durchführten, nach 48 und 72 Std Kulturzeit abbrachen. Aneuploidie. Wir beobachteten in 1,87% sämtlicher untersuchter Zellen eine abnorme Chromosomenzahl. Bei den einzelnen Individuen kamen aneuploide Kerne zwischen 0 und 5% vor, ohne daß ein Unterschied zwischen den Altersgruppen, den Geschlechtern oder den Kulturzeiten bestand. Strukturelle Abnormalitäten. Sie traten in 4,75% aller untersuchten Mitosen, bei den einzelnen Probanden zwischen 1 und 8% auf, wobei Gaps am häufigsten auf den Chromosomen der gruppe D, Brüche auf denen der Gruppe A gefunden wurden. Die Altersgruppen, die Geschlechter, die Präparate der verschiedenen Kulturzeiten und Serien unterschieden sich im Vorkommen von Strukturabnomalitäten nicht voneinander. Assoziationen der akrozentrischen Chromosomen. Ihr Vorkommen ist abhängig von: Individuum, Altersgruppe, Kulturzeit. In einer Altersgruppe für eine bestimmte Kulturzeit charakterisiert ihre Häufigkeit ein Individuum. Satelliten. Sowohl die Häufigkeit der D-Satelliten wie auch die der G-Satelliten ist für ein Individuum charakteristisch. Ihr Vorkommen bei einem Probanden war bei beiden Kulturzeiten gleich.
    Notes: Summary 4754 lymphocyte metaphases of 36 male and female premature babies, new-born babies and infants were analyzed for the occurrence of numeric and structural chromosome aberrations, of associations and visible satellites of the acrocentric chromosomes. The cell cultures were done after a micro-method according to Hirschhorn and were interrupted after 48 and 72 hrs of culturing. Aneuploidy. 1.87% of all the cells analyzed showed an abnormal number of chromosomes. In the single individual aneuploidic nuclei occurred between 0 and 5% without there being a difference in group of age, sex or time in culture. Structural Abnormalities. In 4.75% of the total number of mitoses analyzed, and between 1to 8% in the single individual, structural abnormalities were recorded. Gaps were found most frequently in chromosomes of group D, breaks in those of group A. The difference between age-groups,sexes, culturing time and culture series has no significance for the occurrence of structural abnormalities. Associations of Acrocentric Chromosomes. Their occurrence depends on the individual, the age-group and the time in culture. Within one age-group with a certain culturing time, an individual is characterized by their occurrence. Satellites. The frequency of D-satellites as well as of G-satellites is characteristic of an individual. Their occurrence with one subject remained the same for both culture periods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273029
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...