ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Digitale Medien

Enhancement of Agkistrodon piscivorus piscivorus venom phospholipase A2 activity toward phosphatidylcholine vesicles by lysolecithin and palmitic acid: Studies with fluorescent probes of membrane structure (1995)

Sheffield, Mark J. ; Baker, Brian L. ; Li, Du ; [weitere]

s.l. : American Chemical Society

Biochemistry 34 (1995), S. 7796-7806

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1520-4995

Quelle: ACS Legacy Archives

Thema: Biologie , Chemie und Pharmazie

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1021/bi00024a003

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

2

Digitale Medien

Antioxidant survey to assess antagonism to redox stress using a prokaryotic and an eukaryotic system (1996)

Baker, H. ; DeAngelis, B. ; Frank, O. ; [weitere]

Springer

Cellular and molecular life sciences 52 (1996), S. 597-599

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1420-9071

Schlagwort(e): Glutathione ; free radicals ; antioxidants ; oxidant stressors ; buthionine ; menadione

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie , Medizin

Notizen: Abstract Using a prokaryote (Escherichia coli) and a metazoa-resembling eukaryote (Ochromonas danica), we surveyed antioxidants which might overcome redox stress imposed by menadione sodium bisulphite (MD) and buthionine sulphoximine (BSO). BSO oxidant stress was evident only inO. danica; MD oxidant stress was evident in both organisms. Glutathione, its precursors, e.g. cysteine, homocysteine, and 2-oxo-4-thiazolidine carboxylic acid, and red blood cells, emerged as prime antioxidants for relieving BSO and MD oxidant stress. BSO and MD oxidant activity and antioxidant-annulling effect inO. danica were judged comparable to those found in animal cells whereas the resultsE. coli were not entirely equivalent. TheO. danica system emerged as a practical, rapid, and useful system for pinpointing oxidant stressors and antioxidants, and shows promise for studies with mammalian systems.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/BF01969736

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

3

Digitale Medien

Growth hormone receptor expression in the nucleus and cytoplasm of normal and neoplastic cells (1998)

Lincoln, D. T. ; Sinowatz, Fred ; Temmim-Baker, Labiba ; [weitere]

Springer

Histochemistry and cell biology 109 (1998), S. 141-159

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-119X

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie , Medizin

Notizen: Abstract Growth hormone (GH) exerts its regulatory functions in controlling metabolism, balanced growth and differentiated cell expression by acting on specific receptors which trigger a phosphorylation cascade, resulting in the modulation of numerous signalling pathways dictating gene expression. A panel of five monoclonal antibodies was used in mapping the presence and somatic distribution of the GH receptor by immunohistochemistry in normal and neoplastic tissues and cultured cells of human, rat and rabbit origin. A wide distribution of the receptor was observed in many cell types. Not all cells expressing cytoplasmic GH receptors displayed nuclear immunoreactivity. In general, the relative proportion of positive cells and intensity of staining was higher in neoplastic cells than in normal tissue cells. Immunoreactivity showed subcellular localisation of the GH receptor in cell membranes and was predominantly cytoplasmic, but strong nuclear immunoreaction was also apparent in many instances. Intense immunoreactivity was also observed in the cellular Golgi area of established cell lines and cultured tissue-derived cells in exponential growth phase, indicating cells are capable of GH receptor synthesis. The presence of intracellular GH receptor, previously documented in normal tissues of mostly animal origin, is the result of endoplasmic reticulum and Golgi localisation. Heterogeneity of immunoreactivity was found in normal and neoplastic tissue with a variable range of positive cells. The nuclear localisation of immunoreactivity is the result of nuclear GH receptor/binding protein, identically to the cytosolic and plasma GH-binding protein, using a panel of five monoclonal antibodies against the GH receptor extracellular region. The expression of GH receptors, not only on small proliferating tumour cells such as lymphocytes, but also on well differentiated cells including keratinocytes, suggests that GH is necessary not only for differentiation of progenitor cells, but also for their subsequent clonal expansion, differentiation and maintenance.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/s004180050212

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

4

Digitale Medien

Crystal structure of Escherichia coli manganese superoxide dismutase at 2.1-Å resolution (1998)

Edwards, Ross A. ; Baker, Heather M. ; Whittaker, M. M. ; [weitere]

Springer

JBIC 3 (1998), S. 161-171

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-1327

Schlagwort(e): Key words Superoxide dismutase ; Manganese enzyme ; Crystal structure ; Metalloprotein ; DNA binding

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie , Chemie und Pharmazie

Notizen: Abstract The three-dimensional structure of the manganese-dependent superoxide dismutase (MnSOD) from Escherichia coli has been determined by X-ray crystallography at 2.1 Å resolution. The protein crystallizes with two homodimers in the asymmetric unit, and a model comprising 6528 protein atoms (residues 1–205 of all four monomers), four manganese ions and 415 water molecules has been refined to an R factor of 0.188 (R free 0.218). The structure shows a high degree of similarity with other MnSOD and FeSOD enzymes. The Mn centres are 5-coordinate, trigonal bipyramidal, with His26 and a solvent molecule, probably a hydroxide ion, as apical ligands, and His81, Asp167 and His171 as equatorial ligands. The coordinated solvent molecule is linked to a network of hydrogen bonds involving the non-coordinated carboxylate oxygen of Asp167 and a conserved glutamine residue, Gln146. The MnSOD dimer is notable for the way in which the two active sites are interconnected and a "bridge" comprising His171 of one monomer and Glu170 of the other offers a route for inter-site communication. Comparison of E. coli MnSOD and FeSOD (a) reveals some differences in the dimer interface, (b) yields no obvious explanation for their metal specificities, and (c) provides a structural basis for differences in DNA binding, where for MnSOD the groove formed by dimerization is complementary in charge and surface contour to B-DNA.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/s007750050217

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

5

Digitale Medien

Vocal and visual stimuli enabling copulation behavior in female buntings (1988)

Baker, M. C. ; Baker, A. E. M.

Springer

Behavioral ecology and sociobiology 23 (1988), S. 105-108

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-0762

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Summary The loud and elaborate songs of male songbirds are throught to serve in territorial defense and to stimulate reproductive behavior in the female. We report here that in contrast to several other species, song alone is inadequate to induce sexual (lordosis) behavior in female indigo and lazuli buntings (Passerina cyanea and P. amoena); they require a more elaborate stimulus configuration to develop the full expression of sexual receptivity as indicated by a stereotyped copulation solicitation display. A live male must be present near the female, singing must ensue, and in addition a second and unique vocal utterance must be heard by the female; this is a soft buzzy-sounding vocalization, audible for no more than a few meters, not recognized previously as a critical arousal signal of the male songbird repertoire. Females also utter similar soft sounds in an intimate vocal exchange with the male leading to solicitation of copulation.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/BF00299893

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

6

Digitale Medien

A family of pneumatically-operated thin layer samplers for replicate sampling of heterogeneous water columns (1985)

Baker, Alan L. ; Kromer Baker, Kathleen ; Tyler, Peter A.

Springer

Hydrobiologia 122 (1985), S. 207-211

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1573-5117

Schlagwort(e): microstratification ; thin layer sampler ; heterogeneous water column ; chemocline ; stratification ; meromixis

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Abstract A series of inexpensive, pneumatic thin layer water samplers is described. They can be operated from small boats, and permit sampling at 2.5 cm intervals with little or no disturbance of stratified systems such as oxyclines or redoxclines of meromictic lakes, or microstratification of flagellates in sheltered epilimnia. Some models permit replicate sampling at closely-spaced intervals in a two-dimensional array. Their performance abilities are illustrated with examples of microstratification.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/BF00018280

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

7

Digitale Medien

The occurrence and significance of amino acids in floral nectar (1986)

Baker, H. G. ; Baker, I.

Springer

Plant systematics and evolution 151 (1986), S. 175-186

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1615-6110

Schlagwort(e): Angiosperms. — Nectar ; amino acids ; pollinators ; sample size ; phylogenetic constraint ; evolutionary significance. — Flora of California

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Abstract Approximately 1 500 angiosperm species, in previous papers, have been sampled for the assessment of the amino acids (a. a.) in their nectar. We reaffirm that the findings provide statistically significant data linking differences in the concentration with pollinator type. Flowers that are pollinated by animals that have alternative sources of protein-building a. a.’s show lower a. a. concentration than those that are not. There is a tendency for woody plant nectar a. a.’s to be less concentrated than those of herbaceous plants, but there can be “phylogenetic constraints” which may reduce the correlations of a. a. concentration with pollinator type and with life form. The individual a. a.’s form complements which are qualitatively extremely constant within species. Proline is a normal constituent of many nectars and does not necessarily indicate contamination of the nectar by pollen. Criticism of our findings byGottsberger & al. (1984) is answered by reference to our previous publications and those of other workers, and to the presentation of data from California native species, not published previously. All previous postulates are borne out by these new data with the exception of positive correlations of a. a. concentration with “primitive” and “advanced” floral characteristics taken one at a time, which appear to be inconsistent and are affected strongly by the nature of the family in which they occur. Summary data are provided for families and genera which indicate that high or low a. a. concentration can typify certain families and genera of both relatively “primitive” and relatively “advanced” nature. Needs for future research on an ecosystem basis are quoted.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/BF02430273

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

8

Digitale Medien

Kenrick, J. ; Bernhardt, P. ; Marginson, R. ; [weitere]

Springer

Plant systematics and evolution 157 (1987), S. 49-62

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1615-6110

Schlagwort(e): Angiosperms ; Leguminosae ; Mimosoideae ; Acacia terminalis ; Bee- and bird-pollination ; extrafloral nectaries ; intraspecific variation

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Abstract Intraspecific variation has been found for several pollination-related characteristics in two isolated populations of the self-incompatible treeAcacia terminalis: floral characteristics including colour and flowering time; style length; size and colour of extrafloral nectaries on the leaf petioles; chemical components of the extrafloral nectar; different taxa of bee pollinators; and frequency differences in bird pollinators. These differences possibly reflect the evolution of two different pollination syndromes within this species.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/BF00939180

Permalink