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  • 1
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Net photosynthesis of Picea abies was measured in a spruce forest in northern Germany with temperature- and humidity-controlled cuvettes in 4 different crown layers on shoots of different ages. These measurments were performed such that temperature and humidity either followed ambient conditions or were kept constant. Annual courses of light-, temperature-, and humidity-related net photosynthesis were determined. Spruce had a remarkably constant rate of CO2 uptake from April to September for 1-year and older needles. Light saturation was achieved at 25 klx. Current year needles had the highest rates of CO2 uptake in early summer, but these rates decreased by autumn. Photosynthetic capacity decreased with needle age and, on a dry weight basis, it was higher in the shade than in the sun crown. The temperature optimum was between 13 and 23° C. Photosynthesis in spruce decreased when air humidity was low. The effect of the natural weather conditions on photosynthetic capacity was determined. The habitat is characterized by a high frequency of low light intensities (75% of total daytime below 20 klx) and cool temperatures (80% of daytime between 9 and 21° C). Low air humidity was only present when light intensities were high. The major limiting factor for production was low light intensities, which reduced photosynthetic capacity in the sun crown to 42% below maximum possible rates. Adverse temperatures reduced CO2 uptake by 28% and large water vapor pressure deficits reduced rates by only 2% compared with maximum possible rates. The limited adaptation to light is discussed.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Growth and CO2 uptake in the crown of a spruce tree is described and the production processes of this evergreen conifer are compared with those of a deciduous beech. Spruce had 60% lower rates of net photosynthesis per dry weight than beech. But, beech had a 30% shorter growing season and a 84% smaller biomass than spruce. The annual CO2 gain was 40% lower in beech than it was in spruce. An analysis shows the following conclusions for this habitat. (1) The effect of a prolonged growing season is small. The annual CO2 gain of spruce would be reduced only by 9% if the growing season was the same length as for beech. (2) The annual CO2 gain would increase 14% if all needles in spruce were deciduous, because the current year needles have a higher average rate of CO2 uptake than 3-year old and older needles, but a lower average rate than 1- and 2-year old ones. However, the carbon balance of the tree shows that spruce could not afford to produce the existing needle biomass (14 t ha-1) each year. (3) If spruce were to produce the same deciduous foliage biomass during the same growing season as beech then total production by spruce would be reduced 67%. (4) The annual CO2 uptake by evergreen spruce was higher than deciduous beech not because of a long growing season, but because of the longevity of its needles, which during their total life time (an average of 5 years) have a two to three times greater CO2 uptake than a deciduous leaf in one summer season. The relatively small investment in current year needles produces an annually low, but long lasting assimilation of CO2.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1365-2044
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Until recently, the most appropriate technique of intubating a patient with a cervical spine injury has been the subject of debate. Tracheal intubation by means of the intubating laryngeal mask (Fastrach™), a modified conventional laryngeal mask airway, seems to require less neck manipulation. The aim of this study was to compare the excursion of the upper cervical spine during tracheal intubation using direct laryngoscopy with that during intubation via the laryngeal mask (Fastrach™), by examination of lateral cervical spine radiographs in healthy young patients. The intubating laryngeal mask (Fastrach™) caused less extension (at C1−2 and C2−3) than intubation by direct laryngoscopy. Direct laryngoscopy is still the fastest method to secure an airway provided no intubating difficulties are present. However, in trauma patients requiring rapid sequence induction and in whom cervical spine movement is limited or undesirable, the intubating laryngeal mask (Fastrach™) is a safe and fast method by which to secure the airway.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Anaesthesia 53 (1998), S. 0 
    ISSN: 1365-2044
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science, Ltd
    Plant, cell & environment 25 (2002), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The effects of soil moisture distribution on water uptake of drip-irrigated corn were investigated by simultaneously monitoring the diurnal evolution of sap flow rate in stems, of leaf water potential, and of soil moisture, during intervals between successive irrigations. The results invalidate the steady-state resistive flow model for the continuum. High hydraulic capacitance of wet soil and low hydraulic conductivity of dry soil surrounding the roots damped significantly diurnal fluctuations of water flow from bulk soil to root surface. By contrast, sap flow responded directly to the large diurnal variation of leaf water potential. In wet soil, the relation between the diurnal courses of uptake rates and leaf water potential was linear. Water potential at the root surface remained nearly constant and uniformly distributed. The slope of the lines allowed calculating the resistance of the hydraulic path in the plant. Resistances increased in inverse relation with root length density. Soil desiccation induced a diurnal variation of water potential at the root surface, the minimum occurring in the late afternoon. The increase of root surface water potential with depth was directly linked to the soil desiccation profile. The development of a water potential gradient at the root surface implies the presence of a significant axial resistance in the root hydraulic path that explains why the desiccation of the soil upper layer induces an absolute increase of water uptake rates from the deeper wet layers.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Munksgaard International Publishers
    Contact dermatitis 46 (2002), S. 0 
    ISSN: 1600-0536
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Tacrolimus (FK 506) is a macrolide discovered in 1984 as a metabolic product of Streptomyces tsukabaensis. It has been used successfully in treating atopic dermatitis, allergic contact dermatitis, lichen planus mucosae and pyoderma gangrenosum. In the present study, we evaluated the anti-inflammatory activity of FK 506 in 2 human skin inflammation models. FK 506 as Protopic® cream was tested (i) in a 4-day repetitive irritation test with 2 × daily application of sodium lauryl sulphate (SLS), and (ii) in a UVB erythema model. The effect was evaluated visually and quantified by non-invasive bioengineering methods, namely chromametry and tewametry (TEWL). When FK 506 was applied 30 min after SLS irritation, an increased inflammation in comparison to controls was observed with all 3 methods, with only the TEWL data reaching statistical significance. 1 × daily application of FK 506 for 5 days, starting at the end of the 4-day irritation period, was without any effect. Similarly, no effect of FK 506 was seen in the UVB model. In conclusion, FK 506 was shown to enhance experimentally induced irritant contact dermatitis and not to accelerate healing of irritant contact dermatitis and UVB erythema.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 805 (1996), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 8
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    Unknown
    Paris : Periodicals Archive Online (PAO)
    Etudes anglaises. 29:4 (1976:oct./déc.) 615 
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Arthroskopie 12 (1999), S. 268-273 
    ISSN: 1434-3924
    Keywords: Schlüsselwörter Knie ; Arthroskopie ; Arthrolyse ; Judet-Operation ; Key words Knee ; Arthroscopy ; Arthrolysis ; Judet operation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: The development of minimally invasive and arthroscopic techniques as well as early rehabilitation has brought a significant increase in the functional outcome of joint mobility following knee surgery. Despite this fact, surgeons are still being confronted with an increasing number of knee operations in patients suffering from limited knee motion or arthrofibrosis. Several surgical techniques to improve knee mobility can be performed, depending on the amount and characteristics of immobility. Indications for arthoscopic or open surgery should be based on an algorhithm. The goal of this paper is to present this algorhithm and discuss the limitations of arthroscopic procedures. In seven patients with an average range of motion of 42.8° preoperatively, an open procedure had to be performed. The average range of motion intraoperatively was 115° and 97.8° at follow-up after 22.4 months.
    Notes: Obwohl verfeinerte, minimalinvasive Operationstechniken sowie neue Implantate in der Kniegelenkchirurgie zumeist eine frühfunktionelle Nachbehandlung ermöglichen und eine langfristige Ruhigstellung vermeiden, ist man auch sicher aufgrund der steigenden Zahl an Eingriffen in der täglichen Praxis immer wieder mit Patienten mit störenden Bewegungseinschränkungen des Kniegelenks konfrontiert. Dauer und Art der Gelenksteife, Ausmaß und Sitz des Bewegungshindernisses sowie Umfang der Funktionseinschränkung indizieren zwar die jeweilige Vorgangsweise, die Indikationsstellung gestaltet sich jedoch aufgrund der Komplexität des pathomorphologischen Substrats der Arthrofibrose problematisch. Diese Arbeit versucht anhand der Empfehlungen anderer Autoren sowie eigener Erfahrungen nach 7 offenen Arthrolysen die Grenzen der arthroskopischen Arthrolyse bzw. die Indikation zum offenen Eingriff aufzuzeichnen. Bei den 7 Patienten wurde die Beweglichkeitsamplitude von präoperativ durchschnittlich 42,8° intraoperativ auf einen Wert von durchschnittlich 115° angehoben, fiel jedoch bei der Nachuntersuchung (im Schnitt nach 22,4 Monaten) auf durchschnittlich 97,8° zurück.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Near threshold photoproduction ofη-mesons from the proton has been measured at the MAMI accelerator with the TAPS spectrometer. The mass of theη-meson was deduced from the threshold energy forη-photoproduction. The result of m η =(547.12 ± 0.06 ± 0.25) MeV supports the low value of theη-mass reported from a dp →3Heη measurement at SATURNE in 1992. Theη-decay branching ratio Γ3π0/Γγγ was measured to be (0.832±0.005±0.012).
    Type of Medium: Electronic Resource
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