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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 13 (1990), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract. Suspension cultured cells of Chenopodium rubrum were grown photoautotrophically under a diurnal light-dark cycle of 16-8h. The following phases of the batch culture were differentiated: a short lag, a cell division phase terminated by a pronounced transition to stationary maintenance which finally gradually passed into senescence. Nitrogen fluxes typical of these stages were followed by measuring uptake of NO3 and NH4+ from the medium and their incorporation into the cellular fractions of nitrogenous compounds. Activities of seven N-metabolizing enzymes were determined. Compartmentation of enzymes and nitrogenous compounds was analysed after isolation of intact chloroplasts and vacuoles from protoplasts. Eighty-two per cent of the N originally present in the medium was taken up and incorporated to an extent of 80% into protein until the end of the division phase. Net protein synthesis ceased upon transition to the stationary phase. During the division phase a vacuolar pool of NO3 was established and then maintained throughout the resting phase. Free cellular NH4+ was not localized within the vacuole and responded to the ammonium content of the medium. Amino acids accumulated in the cells especially during the stationary phase, during which they were present in the vacuole. Typical nitrogen relations are portrayed as flux diagrams for one day of each of the essential developmental phases. The enzyme activities were easily sufficient to account for the observed flow rates of the corresponding nitrogenous compounds. Hence, uptake of NO3 and NH4+ must be considered as steps limiting N metabolism in Chenopodium rubrum cell suspensions.
    Type of Medium: Electronic Resource
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  • 2
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    Unknown
    Washington D.C., Wash. : Periodicals Archive Online (PAO)
    Historical methods. 28:3 (1995:Summer) 125 
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  • 3
    ISSN: 1434-601X
    Keywords: 23.20.Lv ; 27.60+j
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract 117Te has been studied via82Se(40Ar,5n)117Te, and a new, substantially extended level scheme is proposed to I≈53/2. Our TRS calculations suggest rotational bands, but with an experimental sensitivity of ≈2%, we see none. Our results differ from those of Sharma, et al, who report two isolated E2 bands. We find them less band-like, being joined at the top and changed in content and order. We suggest a noncollective oblate shape for a new 39/2− level.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 18 (1939), S. 1416-1417 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Der Chirurg 68 (1997), S. 1132-1136 
    ISSN: 1433-0385
    Keywords: Key words: Humeral shaft fractures ; Osteosynthesis ; Intramedullary nailing ; Functional bracing. ; Schlüsselwörter: Oberarmschaftbrüche ; Osteosynthese ; Marknagelung ; funktionelle Behandlung.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung. Es wurden 63 Patienten mit einer Oberarmschaftfraktur durchschnittlich 18 Monate nach Unfall sowohl klinisch als auch radiologisch nachuntersucht. 27 Patienten (Gruppe A) wurden operativ und 36 Patienten (Gruppe B) konservativ behandelt. Die Analyse der Ergebnisse nach einem Punktescore nach Kwasny ergab durchschnittlich 6,7 Punkte für Gruppe A und 2,2 Punkte für Gruppe B zu Gunsten des konservativen Vorgehens (p 〈 0,0001; F = 46,9). In den 2 miteinander vergleichbaren Gruppen war die konservative Therapie der chirurgischen Versorgung von Oberarmschaftbrüchen sowohl bzgl. Beweglichkeit von Schulter- und Ellbogengelenk, Kraftminderung, dem Auftreten neurologischer Störungen und von Schmerzen sowie der subjektiven Bewertung der Behandlung und der Kosmetik durch die Patienten überlegen. Die Auswertung der radiologischen Ergebnisse ergab keine Unterschiede (p = 0,48).
    Notes: Summary. Sixty-three patients with humeral shaft fractures were evaluated clinically and radiographically 18 months after injury; 27 patients were treated surgically (group A) and 36 patients conservatively (group B). Analysis of the results according to a score by Kwasny revealed 6.2 points in group A and 2.2 points in group B (P 〈 0.0001; F = 46.9). The results of these two comparable groups suggest that conservative treatment of humeral shaft fractures is superior regarding mobility of the shoulder and elbow, strength, the incidence of neurological complications, pain, subjective rating and cosmesis. There were no differences on roentgenograms between the two groups (P = 0.48).
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 32-33 (Dec. 1993), p. 111-116 
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-1939
    Keywords: Monoterpene indole alkaloids ; Tropical trees ; Abiotic factors ; Growth ; C/N balance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The growth of Tabernaemontana pachysiphon (Apocynaceae) plants and the alkaloid content of leaves were investigated in the greenhouse at three levels of nutrient supply under two contrasting water and light regimes. We determined height increment, above-ground biomass production, leaf size, specific leaf weight and the content of the alkaloids apparicine, A2, isovoacangine, tubotaiwine and tubotaiwine-N-oxide. The effects of major controlling factors such as light, water and nutrient supply could be directly correlated with growth and were largely independent of each other. In contrast, leaf-alkaloid contents were influenced by interdependencies among the main factors and individually affected in a synergistic or antagonistic manner which deviated from the effects on growth. The following general trends could be identified with respect to the quantitatively predominant alkaloids apparicine, tubotaiwine and isovoacangine. Increasing nutrient supply had a positive effect on both growth and alkaloid content. Drought increased alkaloid content, but retarded growth. High light intensity lowered alkaloid content but promoted growth. We investigated the relationship between primary production and the production of secondary metabolites with respect to relative and total alkaloid content as well as in relation to the leaves' nitrogen status. Our results showed that under conditions of low nutrient supply, higher proportions of leaf nitrogen were allocated to alkaloids than at moderate or high nutrient supply. Under conditions of drought and low light, all plants allocated almost equal proportions of leaf nitrogen to alkaloids, regardless of fertiliser. Total alkaloid content per plant, however, increased with fertilisation. With respect to the N-allocation strategy, we found no indication of a trade-off between primary production and the production of secondary metabolites in this species. Rather, our results are in accordance with the carbon nutrient balance hypothesis.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Archives of gynecology and obstetrics 254 (1993), S. 1053-1054 
    ISSN: 1432-0711
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1432-2048
    Keywords: Key words: Electron paramagnetic resonance ; Frost hardening ; Membrane fluidity ; Photoperiod ; Scots pine ; Thylakoid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. The fluidity of chloroplast thylakoid membranes of frost-tolerant and frost-sensitive needles of␣three- to four-year-old Scots pine (Pinus sylvestris L.) trees, of liposomes produced from the lipids of the thylakoids of these needles, and of liposomes containing varying amounts of light-harvesting complex (LHC) II protein was investigated by means of electron paramagnetic resonance (EPR) measurements using spin-labelled fatty acids as probes. Broadening of the EPR-resonance signals of 16-doxyl stearic acid in chloroplast membranes of frost-sensitive needles and changes in the amplitudes of the peaks were observed upon a decrease in temperature from +30 °C to −10 °C, indicating a drastic loss in rotational mobility. The lipid molecules of the thylakoid membranes of frost-tolerant needles exhibited greater mobility. Moderate frost resistance could be induced in Scots pine needles by short-day treatment (Vogg et al., 1997, Planta, this issue), and growth of the trees under short-day illumination (9 h) resulted in a higher mobility of the chloroplast membrane lipids than did growth under long-day conditions (16 h). The EPR spectrum of thylakoids from frost-tolerant needles at −10 °C was typical of a spin label in highly fluid surroundings. However, an additional peak in the low-field range appeared in the subzero temperature range for the chloroplast membranes of frost-sensitive needles, which represents spin-label molecules in a motionally restricted surrounding. The EPR spectra of thylakoids and of liposomes of thylakoid lipids from frost-hardy needles were identical at +30 °C and −10 °C. The corresponding spectra from frost-sensitive plants revealed an additional peak for the thylakoids, but not for the pure liposomes. Hence, the domains with restricted mobility could be attributed to protein-lipid interactions in the membranes. Broadening of the spectrum and the appearance of an additional peak was observed with liposomes of pure distearoyl phosphatidyl glycerol modified to contain increasing amounts of LHC II. These results are discussed with respect to a loss of chlorophyll and chlorophyll-binding proteins in thylakoids of Scots pine needles under winter conditions.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1432-2048
    Keywords: Key words: Chlorophyll ; Chlorophyll-binding protein ; Frost hardening ; Photosynthesis ; Pinus (frost hardening)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. Photosynthetic CO2 uptake, the photochemical efficiency of photosystem II, the contents of chlorophyll and chlorophyll-binding proteins, and the degree of frost hardiness were determined in three-year-old Scots pine (Pinus sylvestris L.) trees growing in the open air but under controlled daylength. The following conditions were compared: 9-h light period (short day), 16-h light period (long day), and natural daylength. Irrespective of induction by short-day photoperiods or by subfreezing temperatures, frost hardening of the trees was accompanied by a long-lasting pronounced decrease in the photosynthetic rates of one-year-old needles. Under moderate winter conditions, trees adapted to a long-day photoperiod, assimilated CO2 with higher rates than the short-day-treated trees. In the absence of strong frost, photochemical efficiency was lower under short-day conditions than under a long-day photoperiod. Under the impact of strong frost, photochemical efficiency was strongly inhibited in both sets of plants. The reduction in photosynthetic performance during winter was accompanied by a pronounced decrease in the content of chlorophyll and of several chlorophyll-binding proteins [light-harvesting complex (LHC)IIb, LHC Ib, and a chlorophyll-binding protein with MW 43 kDa (CP 43)]. This observed seasonal decrease in photosynthetic pigments and in pigment-binding proteins was irrespective of the degree of frost hardiness and was apparantly under the control of the length of the daily photoperiod. Under a constant 9-h daily photoperiod the chlorophyll content of the needles was considerably lower than under long-day conditions. Transfer of the trees from short-day to long-day conditions resulted in a significantly increased chlorophyll content, whereas the chlorophyll content decreased when trees were transferred from a long-day to a short-day photoperiod. The observed changes in photosynthetic pigments and pigment-binding proteins in Scots pine needles are interpreted as a reduction in the number of photosynthetic units induced by shortening of the daily light period during autumn. This results in a reduction in the absorbing capacity during the frost-hardened state.
    Type of Medium: Electronic Resource
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