Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • 1985-1989  (9)
  • 1980-1984  (5)
Materialart
Erscheinungszeitraum
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 28 (1987), S. 2639-2649 
    ISSN: 1089-7658
    Quelle: AIP Digital Archive
    Thema: Mathematik , Physik
    Notizen: It is well known that the n-fermion algebra is a complex Clifford algebra of dimension 22n with the orthogonal group O(2n,C) as group of automorphisms. The n-boson algebra viewed similarly as a complex "symplectic Clifford'' algebra is investigated. It is of infinite dimension and has the symplectic group Sp(2n,C) as a group of automorphisms. Special attention is given to the case n=1 and various bases. In particular, the matrix elements of the bases between harmonic oscillator states and their relation with special functions are investigated.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1365-2559
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: There are many significant differences, but also considerable overlap between the quantitative histopathological features of mild and marked atypical endometrial hyperplasias and well and moderately differentiated carcinomas, thus preventing its application to individual patient care. To try to overcome this problem, a classification rule for the diagnosis in individual patients, using discriminant analysis has been developed. Utilizing nine quantitative features, all the above four groups can be adequately separated. None of the carcinomas was misclassified as hyperplasia, and only one case of marked atypical hyperplasia was erroneously classified as well differentiated carcinoma, but with a probability of carcinoma 0.75, hyperplasia 0.25. By contrast, the classification probabilities of all the confirmed carcinomas exceeded 0.90. Therefore, using 0.90 as a classification level (‘threshold’), a reliable rule is obtained. A slightly more simple classification rule distinguishes between all the hyperplasias and all the carcinomas. In this way, all the cases of the test set were correctly classified. The classification rules can be used to select patients with benign disease for hormone therapy(Kistner 1973) as an alternative to hysterectomy, and can be programmed in an inexpensive microcomputer. The quantitative techniques are relatively easy, and are capable of being performed in most histopathological laboratories.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1365-2559
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Discrimination between borderline and malignant mucinous ovarian tumours is a well-known diagnostic problem. In order to obtain objective reproducible and consistent features for differential diagnosis, 32 quantitative microscopical features were assessed in 10 benign, 10 borderline and 22 malignant mucinous ovarian tumours. There were many significant differences between the three groups, but using multivariate analysis there was 93% agreement between the histopathological assessment of these sections and the qualitative analyses. The following features were useful in the quantitative classification: the mean area, the mean perimeter and the mean of the short axis of the nucleus; the volume percentage of the epithelium; the mitotic activity. In three cases, there was a difference between the original histopathological and computer classification. It was debatable whether the original diagnosis was correct, and therefore, all the cases were independently reassessed blind by three pathologists. Their diagnoses lend strong support to the computer classification in two of the three cases. The computer classification seems therefore to be even better than 93%. The present quantitative techniques are inexpensive, relatively easy to use, and, we believe, have a useful place in diagnostic histopathology.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    ISSN: 1432-2307
    Schlagwort(e): Bladder cancer ; Grading ; Histomorphometry ; Cytomorphometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Cytomorphometry, using various cytopreparatory techniques on bladder washings and histomorphometry on the resected bladder tumours, was used in an attempt to answer the question: Can cytomorphometry replace histomorphometry for grading of bladder tumours? For the analysis of quantitative data, a probit model was used. Three out of the four cytomorphometric methods provided data supportive to the histomorphometry Using one of the four cytomorphometric methods was sufficient to enhance grading accuracy and all were equally good. Two cases of high grade carcinoma in situ were properly identified by cytomorphometry (as judged on the follow-up data) but the concurrent resected papillary tumours were low grade. These findings indicate that cytomorphometry is a useful method in bladder tumour grading. In some cases it is preferable to histomorphometry.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Histochemistry and cell biology 75 (1982), S. 145-150 
    ISSN: 1432-119X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The administration of monosodium glutamate (MSG) to newborn rats accelerates by two weeks the migration of fluorescent dopaminergic perikarya from the median eminence towards the arcuate nucleus at the time of puberty, which normally occurs from day 22 till 55 after birth. It is hypothesized that MSG affects the trigger mechanism for this migration. The disappearance of fluorescent dopaminergic cells that occurs after MSG administration is considered as a secondary effect.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Histochemistry and cell biology 73 (1981), S. 165-169 
    ISSN: 1432-119X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The transition from infanthood to adulthood is characterized by a sequence of events which are not yet fylly understood. Hormonal changes influencing neuronal circuits in various hypothalamic area are —at least in part — held responsible. Using catecholamine fluorescence techniques in rats it has been found that a displacement of dopaminergic cells can be seen; the fluorescence activity shifting from the median eminence at day 20 after birth to the dorsolateral part of the arcuate nucleus around day 45 after birth, as is the case for catalase positive cells in these areas. It is concluded that the displacement of at least two populations of cells from the median eminence to the arcuate nucleus runs parallel to the onset of puberty. The relation of this shift in respect to the suprachiasmaticpreoptic control will be discussed.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Archives of gynecology and obstetrics 233 (1983), S. 131-140 
    ISSN: 1432-0711
    Schlagwort(e): Chlamydia trachomatis ; CIN
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary We found, as have others, a strong correlation between indirect immunofluorescence techniques and cell culture for the diagnosis ofChlamydia trachomatis infection in material obtained from the cervix. Five epithelial cell types indicative ofChlamydia trachomatis infection (indicator cells) were found in smears in patients with positive immunofluorescence. An attempt to diagnoseChlamydia trachomatis infection in 50 routine smears based on the presence of these indicator cells showed false positives and false negatives so that the diagnosis ofChlamydia trachomatis still requires confirmation by immunofluorescence or culture techniques. The indicator cells frequently had the same morphometric features as cells seen with cervical intraepithelial neoplasia, which may explain why some smears revert to normal after patients are given antibiotics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular histology 19 (1987), S. 658-664 
    ISSN: 1573-6865
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Application of microwaves in histochemistry and cytochemistry generally speeds up the technique. Microwaves stimulate diffusion into the tissue and influence the proteins and membrane of the cell. Silver impregnation techniques for the brain, such as the fast Rio—Hortega or the slow Golgi—Cox technique, normally require a minimum time period of 7 days and 20 days respectively. Using microwaves, the Rio—Hortega technique can be completed within 24 h. In sections prepared from mature brains, good silver impregnation of cell bodies, of axons and their terminals, and of dendrites and their spines are obtained. An explanation is given as to why the method cannot be further reduced in time. To our knowledge, this is the first report of the application of microwave irradiation for colouring pieces of tissue.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular histology 20 (1988), S. 397-404 
    ISSN: 1573-6865
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The activities of various enzymes present in brain homogenates were assayed biochemically (a) with no pretreatment, (b) following a standard microwave treatment in saline and (c) after a standard microwave treatment in formalin. All enzyme activity was lost after the microwave — formalin in treatment. Following microwave — saline treatment, the activities of alkaline phosphatase, 5′-nucleotidase, isocitrate and succinate dehydrogenases were reduced. In contrast, the activities of lactate and malate dehydrogenases were unchanged, and that of acetylcholinesterase apparently increased. Analogous outcomes were seen following attempted histochemical demonstrations of these enzymes. Thus satisfactory histochemical demonstration of all enzymes was achieved (except with alkaline phosphatase, lactate and malate dehydrogenases) following the microwave-saline pretreatment. Since acid phosphatase, catalase and peroxidase were also successfully demonstrated, it seems that microwave-saline pretreatments permit both retention of sufficient enzyme activity for histochemical demonstration to occur and retention of sufficient structural integrity for critical morphological investigations. Since the failure to stain the sites of lactate and malate dehydrogenases is not due to microwave inactivation of these enzymes, their demonstration may be possible by varying the staining procedures.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular histology 20 (1988), S. 335-340 
    ISSN: 1573-6865
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A technique is described to detect bromodeoxyuridine (BrdU) incorporate by cells in S-phase, with a monoclonal antibody, using removable plastic embedding and immunogold-silver staining (IGSS). The incubation times were reduced and the immunological reactions enhanced by microwave irradiation. The embedding in methyl methacrylate enabled us to make thinner sections and it improved the quality of the preparations. The methyl methacrylate did not hinder the reaction of BrdU with the antibody because it could be removed prior to the IGSS procedure. The IGSS procedure appeared to be very sensitive, requiring lower concentrations of the antibodies than other methods. The use of microwave irradiation shortened the time needed to stain a section from 7 to less than 4 h. Furthermore, using microwave irradiation, the concentration of the antibodies needed could be reduced even further compared with the normal IGSS procedure. In sections of the mouse testis and small intestine only nuclei of cells known to be able to proliferate appeared BrdU positive. The non-specific background staining was found to be negligible. In testes of mice that received both3H-thymidine and BrdU more than 95% of the radioactively labelled cells also showed BrdU label and vice versa. This indicates that both methods are equally sensitive for detecting cells in S-phase.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...