ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Springer
    Journal of molecular evolution 16 (1980), S. 95-110 
    ISSN: 1432-1432
    Keywords: Evolutionary Divergence ; DNA ; Single copy ; Thermal Stability ; S1 Nuclease ; Hydroxyapatite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary New methods have been applied to the determination of single copy DNA sequence differences between the sea urchin speciesStrongylocentrotus purpuratus, S. franciscanus, S. drobachiensis, andLytechinus pictus. The thermal stability of interspecies DNA duplexes was measured in a solvent (2.4 M tetraethylammonium chloride) that suppresses the effect of base composition on melting temperature. The lengths of duplexes were measured after digestion with S1 nuclease and correction made for the effect of length on thermal stability. The degree of base substitution that has occurred in the single copy DNA during sea urchin evolution is significantly larger than indicated by earlier measurements. We estimate that 19% of the nucleotides of the single copy DNA are different in the genomes of the two sea urchin congeners,S. purpuratus, andS. franciscanus, which apparently diverged only 15 to 20 million years ago.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular evolution 20 (1984), S. 195-201 
    ISSN: 1432-1432
    Keywords: DNA ; Mobile genetic element ; Enhancer ; Rare maternal transcript
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A comparison has been made between the Sp88 gene regions of the DNAs of the sea urchinsStrongylocentrotus purpuratus (Sp.) andStrongylocentrotus drobachiensis (Sd.). Examination of the 3′ terminal part of the transcribed region revealed a short repetitive sequence present in Sd. but absent from Sp. A 12-nucleotide sequence present once in Sp. is almost perfectly duplicated at both ends of the repeat in Sd., suggesting that a mobile repeat was inserted in the Sd. genome. Other members of this family of repeated sequences occur in many interspersed locations in the genomes of both species. Except for the insertion duplication, the inserted sequence lacks direct or reverse repeats.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 251 (1988), S. 65-70 
    ISSN: 1432-0878
    Keywords: Adipose tissue ; Cell proliferation ; Cell differentiation ; Histochemistry ; Swine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cells in fetal adipose tissue and cells in vitro are characterized by rapid proliferation. Serum factors have been shown to be important for the rapid proliferation of cells in vitro. The present experiment was performed to determine if neuroendocrine regulatory mechanisms of the fetus can influence the actions of serum factors on preadipocyte proliferation and differentiation in vitro. Sera were obtained from decapitated fetal pigs and intact littermates during gestation. Sera were tested for their effects on primary cultures of preadipocytes and stromalvascular cells derived from inguinal adipose tissue of young Sprague-Dawley rats. Coverslip cultures were used for histochemical analysis of enzymes after 12 days of incubation with test media. Analysis of growth curves produced from sequential [3H]-thymidine labeling indicated that fetal age influences rates of proliferation. Sera from decapitated fetal pigs specifically reduced the number of proliferating preadipocytes in culture. Sera from decapitated fetal pigs induced a minimum of 50% less differentiation of sn-glycerol-3-phosphate dehydrogenase activity than sera from intact pigs at all fetal ages. Histochemical staining for enzymes of differentiating preadipocytes was also reduced in cultures incubated with sera from decapitated fetal pigs in comparison to sera from intact pigs. The present study has demonstrated that the in vivo effect of decapitation on fetal adipose tissue development is a consequence of alterations in systemic factors present in serum in response to removal of central regulation by the hypothalamic-pituitary axis.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 250 (1987), S. 185-190 
    ISSN: 1432-0878
    Keywords: Adipocyte ; Proliferation ; Differentiation ; Primary culture ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This experiment was conducted to determine if serum factors are responsible for differences in cellularity of prenatal and postnatal pig adipose tissue as determined by in vitro measurement of cellular proliferation and enzyme-histochemical metabolic development. Cellular proliferation of stromal-vascular cells derived from rat inguinal adipose tissue was measured by [3H]-thymidine incorporation. Coverslip cultures were used for analysis of histochemical differentiation. Cells were incubated in media containing 10% fetal bovine, fetal pig, mature pig, or various combinations of these sera. Fetal bovine serum promoted more [3H]-thymidine incorporation than fetal or postnatal pig sera. Fetal pig sera also stimulated more [3H]-thymidine incorporation than mature pig sera. Sera from adult pigs promoted differentiation and lipid filling of adipocytes. Fetal pig sera stimulated histochemical expression of enzymes, but did not induce lipid filling. Fetal bovine serum produced histochemically undifferentiated cells. Addition of fetal bovine serum to media containing mature pig sera reduced lipid accumulation and histochemical reactivity of cells. This effect of fetal serum was thus due to specific inhibition of lipid deposition and not substrate restriction. These experiments demonstrated that serum factors have a major influence on morphological development of fetal and postnatal adipose tissue.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 1 (1989), S. 149-155 
    ISSN: 1040-452X
    Keywords: Gene regulation ; Echinoderm ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We report the first measurements of cell number, total RNA, and transcript accumulations for two actin genes during larval development of the sea urchin Strongylocentrotus purpuratus. At 5 weeks of feeding, when development of laboratory-raised larvae is completed, the cell number has increased about 100-fold with respect to the pluteus-stage embryo to about 150,000 ± 50,000, and the total RNA has increased 46-fold to about 130 ng per larva. The transcripts of the Cylla cytoskeletal actin gene, which is expressed in adult tissues, continue to accumulate throughout larval development. A contrasting pattern of transcript accumulation is observed for Cyllla, a different cytoskeletal actin gene that in the embryo is expressed only in aboral ectoderm. These transcripts increase in number early in larval development, when the larval epidermis is differentiating, and then decline in quantity. It is known that at metamorphosis the larval epidermis is largely histolyzed and that the Cyllla gene is not expressed in the juvenile or adult.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 25 (1990), S. 110-122 
    ISSN: 1040-452X
    Keywords: DNA-protein interactions ; Embryonic gene regulation ; Regulatory factors ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Expression of the Cylla cytoskeletal actin gene is a marker of differential gene activation in the aboral ectoderm of the early sea urchin embryo. Gene transfer expreiments have defined a 2,300 nucleotide cis-regulatory domain required for the correct spatial and temporal control of this gene. This domain includes at least 20 sites at which relatively stable DNA-protein complexes form in vitro on reaction with embryo nuclear extracts. We report the nucleotide sequence of the whole regulatory domain and map the sites at which high-specificity DNA-protein interactions occur. These were located initially by gel shift assays carried out on progressive restriction digests of given subfragments of the large regulatory domain and were located more exactly by oligonucleotide gel shift competitions. Eight of the sites of specific interaction are unique within the Cyllla regulatory domain, and the remainder consist of five different sites that occur more than once. We observe some well known sequences also found in regulatory regions of other genes, e.g., “CCAAT” and “octamer” elements. The various sites have been classified regarding putative biological function in other work, and the present studies permit an assessment of the number and complexity of interactions constituting each functional class and of the relative locations of sites of each class.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Philadelphia : Wiley-Blackwell
    Journal of Cellular and Comparative Physiology 62 (1963), S. 43-47 
    ISSN: 0095-9898
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Electron Microscopy Technique 14 (1990), S. 298-306 
    ISSN: 0741-0581
    Keywords: Colloidal gold ; Critical point drying ; Hairy cell leukemia ; Interleukin-2 receptor ; Macrophages ; Lymphokine-activated killer cells ; Peldri II ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: For many years critical point drying (CPD) has been the method of choice for preparing cells for scanning electron microscopy (SEM). Described herein is a simple, efficient, inexpensive, reproducible, and safe procedure using Peldri II, a proprietary fluorocarbon compound that is solid at room temperature and a liquid above 25°C, as a sublimation dehydrant for processing specimens for SEM. The utility of Peldri II was demonstrated in studies using leukocytes from the blood of healthy donors and patients with leukemia as well as from long-term lymphoblastoid cell lines. The application of the proposed Peldri II procedure was further documented in SEM studies in which the expression and distribution of the interleukin-2 receptor (IL-2R) on leukocyte surface membranes was imaged using colloidal gold-labeled antibodies (i.e., immunogold). When compared with current SEM preparation procedures using CPD, Peldri II is a useful alternative that is thought to offer several important advantages.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...