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  • 1
    ISSN: 1432-1939
    Schlagwort(e): Key words C use efficiency ; Chronosequence ; Metabolic quotient ; Microbial biomass ; Phospholipid fatty acid
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We studied microbial community composition in a primary successional chronosequence on the forefront of Lyman Glacier, Washington, United States. We sampled microbial communities in soil from nonvegetated areas and under the canopies of mycorrhizal and nonmycorrhizal plants from 20- to 80-year-old zones along the successional gradient. Three independent measures of microbial biomass were used: substrate-induced respiration (SIR), phospholipid fatty acid (PLFA) analysis, and direct microscopic counts. All methods indicated that biomass increased over successional time in the nonvegetated soil. PLFA analysis indicated that the microbial biomass was greater under the plant canopies than in the nonvegetated soils; the microbial community composition was clearly different between these two types of soils. Over the successional gradient, the microbial community shifted from bacterial-dominated to fungal-dominated. Microbial respiration increased while specific activity (respiration per unit biomass) decreased in nonvegetated soils over the successional gradient. We proposed and evaluated new parameters for estimating the C use efficiency of the soil microbial community: “Max” indicates the maximal respiration rate and “Acc” the total C released from the sample after a standard amount of substrate is added. These, as well as the corresponding specific activities (calculated as Max and Acc per unit biomass), decreased sharply over the successional gradient. Our study suggests that during the early stages of succession the microbial community cannot incorporate all the added substrate into its biomass, but rapidly increases its respiration. The later-stage microbial community cannot reach as high a rate of respiration per unit biomass but remains in an “energy-saving state,” accumulating C to its biomass.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Biology and fertility of soils 18 (1994), S. 80-82 
    ISSN: 1432-0789
    Schlagwort(e): Biological variation ; Coniferous forest ; Near-infrared spectrum ; Partial least-square regression ; Microbial biomass ; Soil respiration
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Near-infrared spectroscopy and soil physicochemical determinations (pHH2O, organic matter content, total C content, NH inf4 sup+ , total N content, cation-exchange capacity, and base saturation) were used to characterize fire-or wood ash-treated humus samples. The spectroscopic and the soil physicochemical analysis data from the humus samples were used separately to explain observed variations in soil respiration and microbial biomass C by partial least-square regression. The first regression component obtained from the physicochemical and spectroscopic characterization explained 10–12% and 60–80% of the biological variation, respectively. This suggests that information on organic material collected from near-infrared spectra is very useful for explaining biological variations in forest humus.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Biology and fertility of soils 23 (1996), S. 7-14 
    ISSN: 1432-0789
    Schlagwort(e): Key words Acid rain ; Coniferous humus ; Ergosterol ; Microbial biomass ; Muramic acid ; Soil respiration ; Subarctic areas
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Humus chemistry and respiration rate, ATP, ergosterol, and muramic acid concentration as measures of chemical properties, microbial activity, biomass, and indicators of fungal and bacterial biomass were studied in a long-term acid rain experiment in the far north of Finnish Lapland. The treatments used in this study were dry control, irrigated control (spring water, pH 6), and two levels of simulated acid rain (pH 4 and pH 3). Originally (1985–1988), simulated acid rain was prepared by adding both H2SO4 and HNO3 (1.9:1 by weight). In 1989 the treatments were modified as follows. In subarea 1 the treatments continued unchanged (H2SO4+HNO3 in rain to pH 4 and pH 3), but in subarea 2 only H2SO4 was applied. The plots were sampled in 1992. The acid application affected humus chemistry by lowering the pH, cation exchange capacity, and base saturation (due to a decrease in Ca and Mg) in the treatment with H2SO4+HNO3 to pH 4 (total proton load over 8 years 2.92 kmol ha–1), whereas the microbial variables were not affected at this proton load, and only the respiration rate decreased by 20% in the strongest simulated acid rain treatment (total proton load 14.9 kmol ha–1). The different ratios of H2SO4+HNO3 in subareas 1 and 2 did not affect the results.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Biology and fertility of soils 23 (1996), S. 7-14 
    ISSN: 1432-0789
    Schlagwort(e): Acid rain ; Coniferous humus ; Ergosterol ; Microbial biomass ; Muramic acid ; Soil respiration ; Subarctic areas
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Geologie und Paläontologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Humus chemistry and respiration rate, ATP, ergosterol, and muramic acid concentration as measures of chemical properties, microbial activity, biomass, and indicators of fungal and bacterial biomass were studied in a long-term acid rain experiment in the far north of Finnish Lapland. The treatments used in this study were dry control, irrigated control (spring water, pH 6), and two levels of simulated acid rain (pH 4 and pH 3). Originally (1985–1988), simulated acid rain was prepared by adding both H2SO4 and HNO3 (1.9:1 by weight). In 1989 the treatments were modified as follows. In subarea 1 the treatments continued unchanged (H2SO4+HNO3 in rain to pH 4 and pH 3), but in subarea 2 only H2SO4 was applied. The plots were sampled in 1992. The acid application affected humus chemistry by lowering the pH, cation exchange capacity, and base saturation (due to a decrease in Ca and Mg) in the treatment with H2SO4+HNO3 to pH 4 (total proton load over 8 years 2.92 kmol ha-1), whereas the microbial variables were not affected at this proton load, and only the respiration rate decreased by 20% in the strongest simulated acid rain treatment (total proton load 14.9 kmol ha-1). The different ratios of H2SO4+HNO3 in subareas 1 and 2 did not affect the results.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Annals of hematology 44 (1982), S. 241-247 
    ISSN: 1432-0584
    Schlagwort(e): Immunotherapy ; Corynebacterium parvum ; Cytostatic therapy ; Hemostasis ; Fibrinopeptide A
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The effect of an immunotherapy with Corynebacterium parvum on the blood coagulation system was investigated in a randomized trial of 18 patients with metastatic breast cancer. All patients received cytostatic therapy. Additionally, C. parvum was given intravenously on day 15 of the cytostatic cycle (group I) or on day 1 (group II) or not at all (group III). Fibrinopeptide A increased within 2 h after intravenous administration of C. parvum in groups I and II and normalized after 24 h (p〈0.05). Platelet counts decreased continuously in all treatment groups (p〈0.05). Prothrombin time, fibrinogen concentration, factor VIII:C and factor VIIIR:Ag were not affected. The fibrinolytic activity showed a slight but not statistically significant increase after intravenous administration of C. parvum. The data suggest that plasma hypercoagulability is induced or enhanced in man even after small intravenous doses of C. parvum.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    ISSN: 1432-1440
    Schlagwort(e): Corynebacterium parvum ; Chemotherapy ; Metastatic breast cancer ; Corynebacterium parvum ; Chemotherapie ; metastasierendes Mammakarzinom
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Seit September 1975 haben wir 156 Patientinnen mit metastasierenden Mammakarzinomen in eine prospektive multizentrische Studie aufgenommen. Alle Patientinnen erhielten 6 Zyklen Vincristin, Adriamycin und Cyclophosphamid (VAC) und anschließend weiterhin monatlich einmal 5-Fluorouracil, Methotrexat und Cyclophosphamid (FMC), bis eine Tumorprogression dokumentiert wurde. Auf Grund randomisierter Zuweisung erhielt etwa die Hälfte der Patientinnen zusätzlich subkutan Injektionen von Corynebacterium parvum jeweils am Tag 1 eines Chemotherapiezyklus (VAC/FMC). Bei den 150 auswertbaren Patientinnen fanden sich 33 von 76 (45%) bzw. 36 von 74 (49%) komplette oder partielle Remissionen unter Chemotherapie ohne bzw. mit Zusatz von Corynebacterium parvum. Die Kaplan-Maier-Kurven für die Dauer der Remissionen und des Überlebens waren bei beiden Kollektiven fast identisch (mediane Remissionsdauer 14,5 bzw. 12,1 Monate und mediane Überlebenszeit 22,2 bzw. 21,1 Monate). Die hämatologischen und gastrointestinalen Nebenwirkungen waren bei beiden Gruppen ebenfalls ähnlich. Auffällig war jedoch, daß 19 von 74 (26%) Patientinnen als Folge der wiederholten subkutanen Injektionen von Corynebacterium parvum Hautulcera entwickelten. Diese Patientinnen zeigten die längste Überlebenszeit (p=0.002, log rank test). Diese Ergebnisse lassen vermuten, daß eine unspezifische Immunstimulation mit Corynebacterium parvum am Tag 1 der heute üblichen Polychemotherapie den meisten Patientinnen mit metastasierenden Mammakarzinomen nichts nützt, sondern eine „immunreaktive“ Untergruppe mit gesteigerter lokaler Toxizität und Überlebenszeit selektioniert.
    Notizen: Summary A total of 156 patients with metastatic breast cancer were entered into a prospective multicenter trial in September 1975. All patients were treated monthly with vincristine, adriamycin and cyclophosphamide (VAC) six times, followed by 5-fluorouracil, methotrexate and cyclophosphamide (FMC) until progression was documented. By random assignment, the patients received 5 mg/m2 Corynebacterium parvum (CP) subcutaneously on day 1, in addition to VAC/FMC. Of the 150 evaluable patients, 33 of 76 (45%) and 36 of 74 (49%) had complete or partial response to VAC/FMC plus CP, respectively. The Kaplan-Maier curves of duration of remission and survival were almost identical (medians 14.5 vs 12.1 months and 22.2 vs 21.1 months, respectively). The hematologic and gastrointestinal toxicity were also similar in the two study groups. However, 19 of 74 (26%) patients developed skin ulcers after repeated injections of CP. These patients showed prolonged survival (P=0.002, log rank test). These results suggest that adding nonspecific immunostimulation with CP to currently available chemotherapy on day 1 is of no benefit to most patients with metastatic breast cancer, but may select an ‘immunoreactive’ subgroup with increased local toxicity and survival.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    ISSN: 1432-1440
    Schlagwort(e): Metastatic breast cancer ; Corynebacterium parvum ; Comparison of different times and routes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary From January 1978 to December 1980, 222 patients with metastatic breast cancer were included into a prospective multicenter trial. All patients were treated once a month with six cycles of VAC- (vincristine, adriamycin, cyclophosphamide) chemotherapy, followed by FMC (5-fluor-ouracil, methotrexate, cyclophosphamide) until progression was documented. By random assignment, the patients received immunostimulation with Corynebacterium parvum (CP) by one of four methods: subcutaneous (SC) on either day 1 or day 14, intravenous (IV) on either day 1 or day 14. The 214 evaluable patients were equally distributed to the four arms. The rates of complete or partial response to VAC/FMC plus CP did not differ significantly between the treatment groups. Of our patients, 22–33% were definite treatment failures. The Kaplan-Meier curves of duration of remission (medians 14 vs. 9 vs. 13 vs. 11 months) did not differ significantly. Only small differences in survival were noted among the four study groups (medians 15.4 vs. 17.5 vs. 17.2 vs. 13.0 months). However, complete and partial responders lived significantly longer (Log rank testP=0.008), when CP was given on day 14 by the SC rather than IV route (29+ vs. 14.3 months). Patients in the four study groups were treated with virtually identical doses of VAC/FMC chemotherapy. Patients receiving CP intravenously on day 14 experienced significantly lower mean leukocyte counts than patients in the other groups. Many patients suffered from high temperature (requiring treatment with antipyretics) and severe gastrointestinal toxicity, particularly when CP was given IV on day 1 together with the chemotherapy. Sixteen patients developed skin ulcers following repeated SC injections of CP. They showed a 4-month longer median survival than patients without these local reactions. Taken together, the results suggest that adding CP in the ways tested to monthly VAC/FMC chemotherapy is of no benefit to patients with metastatic breast cancer.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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