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
    Daily fluctuations of titratable acidity, content of organic acids (malate and citrate) and soluble sugars of varieties and wild relatives of Ananas comosus L. growing under natural tropical conditions (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 16 (1993), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The genus Ananas has its centre of origin in northern South America. In this area, several varieties of Ananas comosus are widely cultivated, and a number of wild species are found growing under variable conditions of light intensity, soil fertility and water availability. Here we report detailed daily courses of titratable acidity, and malate, citrate and free-sugars content of several cultivated varieties of A. comosus and of A. ananassoides, a closely related species growing on granitic rock-outcrops in southern Venezuela. Day-night oscillations of both malate and citrate were detected in plants growing under full sun, but malate was by far the most important organic anion associated with CAM performance in ail populations sampled. Fructose was the dominant compound in the neutral fraction, but only sucrose showed a consistent inverse relation with the cycle of titratable acidity. The diel oscillations of free sugars measured were not always enough to account for the amount of organic anions accumulated during the night. Plants cultivated under shady conditions always showed a lower night-time increase in titratable acidity and organic acids, and also smaller oscillations in the amount of free sugars than sun exposed plants. In all populations growing under full sun, osmolality increased during the night, but it was not always possible to explain these changes on the basis of variations in molar concentrations of organic acids and sugars. Besides, no diel variations in the cations K+, Ca2+ and Mg2+ were detected. K+ was always the dominant cation (K/Ca ratios ∼ 19), while Mg2+ was always higher than Ca2+ (Mg/Ca ∼ 2).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.1993.tb00844.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Associative ERP effects with memories of artificial faces
    Amsterdam : Elsevier
    Cognitive Brain Research 2 (1994), S. 39-48 
    Details
    ISSN: 0926-6410
    Keywords: Event-related potential ; Face ; N400 ; Priming
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine , Psychology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0926-6410(94)90019-1
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Calcium Fluxes, Ion Currents and Dihydropyridine Receptors in a New Immortal Cell Line from Rat Heart Muscle
    Amsterdam : Elsevier
    Journal of Molecular and Cellular Cardiology 25 (1993), S. 829-845 
    Details
    ISSN: 0022-2828
    Keywords: Calcium channels ; Calcium flux ; Cardiac cell line ; Cell transformation ; Cultured heart muscle ; Dihydropyridine receptors ; Ion channels
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1006/jmcc.1993.1093
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    An ERP Study of Expectancy Violation in Face Perception
    Amsterdam : Elsevier
    Brain and Cognition 26 (1994), S. 1-22 
    Details
    ISSN: 0278-2626
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine , Psychology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1006/brcg.1994.1039
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Incongruence negativities elicited by words and faces: Different scalp distributions
    Amsterdam : Elsevier
    International Journal of Psychophysiology 11 (1991), S. 83 
    Details
    ISSN: 0167-8760
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine , Psychology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0167-8760(91)90348-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Different ERP effects related to visual and semantical incongruition during face processing
    Amsterdam : Elsevier
    International Journal of Psychophysiology 14 (1993), S. 140 
    Details
    ISSN: 0167-8760
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine , Psychology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0167-8760(93)90216-C
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    MEMBRANE ANTIGENS RECOGNIZED BY HETEROANTISERA AGAINST MOUSE TUMOURS, TESTED IN CELL LINES OF DIFFERENT H - 2 HAPLOTYPES (1978)
    Oxford, UK : Blackwell Publishing Ltd
    International journal of immunogenetics 5 (1978), S. 0 
    Details
    ISSN: 1744-313X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The pattern of reactivity of two heteroantisera against mouse tumour cells (rabbit anti-Meth A sarcoma: RAMA; and rabbit anti-RBL-5 leukaemia: RAR-5) has been studied in various cell lines of different H-2 haplotypes in complement-dependent cytotoxicity tests using a microadioassay.RAMA was cytotoxic not only for Meth A (H-2d) but also for MCG4, P815Y, LSTRA, YC8 (H-2d), L929, TLC5, Gardner (H-2k), RBL-5 and TLX/9 (H-2b). RAR-5 similarly killed RBL-5, as expected, as well as Meth A, P815Y, MCG4, SL2, YC8, LSTRA (H-2d), L929 (H-2k), TLX/9, MBL2, Gil IV, EL4 (H-2b) and YAC (H-2a).The cross-cytotoxicity RAMA-RBL-5 and RAR-5-Meth A was abolished when RAMA or RAR-5 were absorbed with allogeneic tissues from C57B1/6, BALB/c, CBA/H, C57B1/10 (B10), B10.BR, B10.D2, but not with rat lymphoid cells. A species-specific antigen present in these strains of mice thus appeared to be responsible for this cytotoxicity.The direct killing obtained with RAMA on Meth A and RAR-5 on RBL-5 was not absorbed by: (a) allogeneic cells of C57B1/6, CBA/H, AKR, B10, B10.BR, B10.D2 for RAMA, and CBA/H, BALB/c, B10, B10.BR, B10.D2 for RAR-5; or (b) syngeneic normal lymphoid cells (BALB/c and C57B1/6 respectively).This suggests the presence of a heteroantibody in the sera recognizing structures at the tumour cell surface that are absent in normal lymphoid cells—a tumour-specific antigen (TSA).Finally, the TSA of Meth A (recognized by BALB/c-absorbed RAMA) did not cross-react with eight mouse cell lines of different aetiology and origin: MCG4, P815Y, Gardner, TLC5, L929, TLX/9, LSTRA and RBL-5. However, the TSA of RBL-5 (recognized by C57B1/6 absorbed RAR-5) reacted not only with RBL-5 but also with tumour cells induced by viruses antigenically related to Rauscher, belonging to the group FMR Gi. It reacted also with EL4, a tumour cell line not virus induced, and weakly with SL2, a spontaneous tumour cell line. It did not react with TLX/9 (X-ray induced) or Meth A (chemically induced).From these results it is concluded that heteroantisera against mouse tumour cells recognize at least species-specific antigens and tumour-specific antigens.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1744-313X.1978.tb00660.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Application of flow cytometry to the study of antiphagocytic properties of Klebsiella pneumoniae capsular polysaccharide (1993)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS immunology and medical microbiology 7 (1993), S. 0 
    Details
    ISSN: 1574-695X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Abstract We used flow cytometry to compare the effects of whole cells and capsular polysaccharides of Klebsiella pneumoniae on the phagocytic ability ot polymorphonuclear leukocytes. Our results showed a light descrease in phagocytic activity in the presence of capsular polysaccharides, but a marked decrease with whole cells. Our findings suggest that the resistance to phagocytosis in these microorganisms is not due exclusively to their capsule, as claimed by other authors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-695X.1993.tb00382.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Relationships between carbon and hydrogen isotope ratios and nitrogen levels in leaves ofClusia species and two other Clusiaceae genera at various sites and different altitudes in Venezuela (1996)
    Springer
    Trees 10 (1996), S. 351-358 
    Details
    ISSN: 1432-2285
    Keywords: Altitude ; Carbon isotope ratio ; Clusiaceae ; Crassulacean acid metabolism ; Deuterium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Samples of the Clusiaceae generaClusia, Oedematopus andDystovomita were collected at various sites and different altitudes in northern and south-western Venezuela. Analyses of stable isotopes of carbon and hydrogen and of leaf-nitrogen levels were performed on the dried samples. Correlations among these variables, i.e. carbon isotope discrimination (Δ), hydrogen isotope ratio (δD) and N-levels, and with altitude were assessed. In the samples, where values of Δ above 15‰ indicate predominant performance of C3 photosynthesis, there were slight tendencies of increasing Δ, δD and N-levels with increasing altitude and of increasing Δ with increasing N. Although these correlations taken separately were not statistically significant, they support each other and indicate increasing transpiration and increased leaf-nutrient supply at increasing altitude. Performance of crassulacean acid metabolism (CAM) in species ofClusia appears to be restricted to altitudes below 1500 m a.s.l. There was a significant negative correlation of Δ with altitude in the samples, where values of Δ below 10‰ indicated predominant performance of CAM. This suggests that phases II and IV of CAM are progressively suppressed towards the upper altitudinal limit of CAM inClusia in northern Venezuela. It is concluded that among the large number of environmental factors and combinations thereof, which determine the expression of CAM inClusia and trigger C3-CAM transitions in C3/CAM intermediate species, low availability of water is the most important.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02185638
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Prolonged leaf senescence in Clusia multiflora H.B.K. (1997)
    Springer
    Trees 11 (1997), S. 370-377 
    Details
    ISSN: 0931-1890
    Keywords: Key words Clusia multiflora ; Foliar aging ; Leaf weightper area ; Senescence ; Tropical montane forest
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract  Leaf aging and senescence in Clusia multiflora H.B.K. was investigated by artificial treatments, such as floating leaf discs on water in darkness, or darkening leaves attached to the parent plant in situ in trees living in a tropical cloud forest. In both cases several parameters modified by age were evaluated such as nitrogen levels, chlorophyll content, succulence and carbohydrates levels. A prolonged senescence (nearly 3 months in floating leaf discs) was observed, contrasting with species such as Heliocarpus americanus (5 days) and Cecropia palmatisecta (20 days), characterized by low values of leaf weight per area, but similar to species with high leaf weight per area and with high levels of organic acids such as Clusia minor and Fourcroya humboldtiana, where acids may act as a reserve of C and energy. After 30 days in darkness C. multiflora leaf samples collected in the field did not show differences in comparison to non-darkened opposite leaves with respect to chlorophyll, titratable protons and carbohydrates, and leaves performed photosynthesis after 2 months in darkness. The effect of age in leaves was evaluated in a gradient of leaves, sampled at different positions from the apex and ranging in age from 15 days to 2 years old. The study of senescence in tropical wild plants is uncommon, but it is important knowledge for understanding foliar development, and response to internal rather than environmental regulation in climates where seasons are not strongly marked as is the case in the tropical mountain forest, where C. multiflora constitutes an important component in the early successional vegetation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00009681
    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...