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  • 1
    ISSN: 1432-1939
    Keywords: Air pollution ; Acid rain ; Photosynthesis ; Nutrition ; Picea abies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Photosynthetic rates and nutrient contents of spruce needles were measured in a region with high levels of air pollution in NE Bavaria, Germany (FRG), and compared to spruce grown under clean air conditions at Craigieburn, in the South Island of New Zealand (NZ). The absolute rates of CO2 uptake, the slope of the CO2 response curve at 240 μl l−1 internal CO2 concentration, and the change of photosynthetic rates with needle age at ambient and saturated CO2 concentrations were virtually identical at both measuring sites. These results confirm an earlier conclusion, that there is no long-term effect of atmospheric pollutants directly on photosynthetic CO2 uptake rates with persistent exposure at the FRG site to high levels of anthropogenic air pollution. Photosynthetic capacity at saturating CO2 concentration was three times higher in the NZ spruce. Needles with high photosynthetic capacity in NZ had lower nitrogen and higher calcium concentrations per unit dry weight but higher concentrations of nitrogen, phosphorus, potassium, magnesium and calcium per unit leaf area, and twice the specific leaf weight.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-1939
    Keywords: Photosynthesis ; Specific leaf weight ; Carbon balance ; Larix ; Picea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Canopy photosynthesis is difficult to measure directly or to predict with complex models demanding knowledge of seasonal variation in environmental and physiological properties of the canopy. Trees in particular offer a challenge with their large, aerodynamically rough and seasonally-changing canopy properties. In this paper we assess the possibility of using specific leaf weight to predict seasonal and annual net photosynthetic rate in deciduous (Larix sp.) and evergreen (Picea abies) conifers. Annual photosynthetic rate and specific leaf weight of different positions of the crown in both species were highly correlated (r 2=0.930). Annual carbon uptake by different segments in a mature P. abies crown was closely related to leaf biomass. The relationship was improved by adjusting the leaf biomass of each segment in regard to its specific leaf weight relative to the maximum found in the canopy. The adjustment accounted for associated differences in photosynthetic activity. This combined structural index (leaf biomassxrelative specific leaf weight) could, when calibrated, predict the total annual carbon uptake by different parts of the crown. If direct measurements of photosynthesis are not available, the combined structural index may still serve as a comparative estimator of annual carbon uptake.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-1939
    Keywords: Picea abies ; Forest decline ; Stomatal response ; Photosynthesis ; Mg-deficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary CO2 assimilation rate (A) and leaf conductance (g) were measured in the field on intact branches of 35-year-old Picea abies (L.) Karst. trees, in five plots each in a healthy and a declining stand. The declining site included trees with yellow needles. In order to separate atmospheric effects on gas exchange from effects of nutrient deficiency, direct effects of atmospheric pollutants were studied on green needles of different age classes in plots of trees at different stages of visible decline. The effects of nutrient deficiency on gas exchange were studied on a different group of trees showing needles of various degrees of yellowing. CO2 assimilation of green needles at the same leaf conductance fell somewhat only when needles had reached 5 years of age, the oldest age examined in this study. Leaf conductance decreased with increasing needle age, but green needles in the declining stand had leaf conductances similar to those of needles in the healthy stand. Stomata of needles with different magnesium concentrations responded to light and air humidity in all age classes. Thus, as long as needles were green, no dese effect was detectable up to 5 years of exposure to atmospheric emissions. Since all needles, green and yellow, were exposed to the same pollution levels, differences in gas exchange between green and yellow needles could not be explained simply in terms of long-term direct effects of air pollution. Needle magnesium contents were correlated with needle yellowing. Neither needle color change nor the magnesium concentration were related to g, but CO2 uptake at ambient CO2 levels declined with lower magnesium concentration and greater degrees of needle yellowing.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 55 (1977), S. 1021-1023 
    ISSN: 1432-1440
    Keywords: Platelet function ; impaired ; Bleeding time ; Platelet aggregation ; Synthetic penicillins ; Hemostasis ; Prevention of thrombosis ; Postoperative Bleeding ; Antithrombin ; Plättchenaggregation ; Plättchenfunktionsstörung ; Blutungszeit ; Synthetische Penicilline ; Hämostasestörung ; Thromboseprophylaxe ; Postoperatives Blutungsrisiko ; Antithrombin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei fünf nierengesunden Patienten und zwei Patienten mit geringfügig eingeschränkter Nierenfunktion (Ccr 60–70 ml/min×1,73 m2) führten therapeutische Dosen von Carbenicillin (3×10 g/24 h) nach 12–24 h zu einer deutlichen Verlängerung der nach Ivy gemessenen Blutungszeit (Medianwert vor Therapie zwischen 4 min 08 s–4 min 18 s; nach 24 h 15–20 min, nach 72 h〉30 min). Die Blutungsverlängerung wurde bei Serumspiegeln zwischen 13 und 180 µg/ml beobachtet. Nach Beendigung der Carbenicillingabe war die Blutungszeitverlängerung selbst nach vollständiger renaler Elimination des Medikaments noch für die Dauer von 4 Tagen nachweisbar. Dosiserhöhung führte zur Verstärkung der Thrombozytenfunktionsstörung. Auf die mögliche klinische Bedeutung dieses Befundes (postoperative Blutungsbereitschaft, Interaktion mit anderen gerinnungshemmenden Substanzen, Blutungsbereitschaft bei Thrombopenie) wird hingewiesen.
    Notes: Summary After therapeutic doses of carbenicillin (3×10 g/24 h) prolongation of bleeding time, measured according to Ivy, was observed (median time prior to therapy 4 min 08 s–4 min 18 s; 24 h after therapy 15–20 min; 72 h after therapy 〉30 min) in 5 patients with normal renal function and 2 patients with slight impairment of renal function (Ccr 60–70 ml×1.73 m2). Prolongation of bleeding time was observed at serum concentrations between 13 and 180 µg/carbenicillin/ml. After carbenicillin was withdrawn, prolongation of bleeding time was demonstrable for 4 days, i.v. even after the drug had been eliminated completely by urinary excretion. Higher doses of carbenicillin caused more severe disturbances of platelet function. The finding of prolonged bleeding time after carbenicillin may have clinical relevance (e.g. interaction with other anticoagulants, p.o. wound bleeding, gastro-intestinal hemorrhage, thrombopenia).
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Annals of hematology 44 (1982), S. 241-247 
    ISSN: 1432-0584
    Keywords: Immunotherapy ; Corynebacterium parvum ; Cytostatic therapy ; Hemostasis ; Fibrinopeptide A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: 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.
    Type of Medium: Electronic Resource
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