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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Inc
    Journal of metamorphic geology 21 (2003), S. 0 
    ISSN: 1525-1314
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: Zircon from a lower crustal metapelitic granulite (Val Malenco, N-Italy) display inherited cores, and three metamorphic overgrowths with ages of 281 ± 2, 269 ± 3 and 258 ± 4 Ma. Using mineral inclusions in zircon and garnet and their rare earth element characteristics it is possible to relate the ages to distinct stages of granulite facies metamorphism. The first zircon overgrowth formed during prograde fluid-absent partial melting of muscovite and biotite apparently caused by the intrusion of a Permian gabbro complex. The second metamorphic zircon grew after formation of peak garnet, during cooling from 850 °C to c. 700 °C. It crystallized from partial melts that were depleted in heavy rare earth elements because of previous, extensive garnet crystallization. A second stage of partial melting is documented in new growth of garnet and produced the third metamorphic zircon. The ages obtained indicate that the granulite facies metamorphism lasted for about 20 Myr and was related to two phases of partial melting producing strongly restitic metapelites.Monazite records three metamorphic stages at 279 ± 5, 270 ± 5 and 257 ± 4 Ma, indicating that formation ages can be obtained in monazite that underwent even granulite facies conditions. However, monazite displays less clear relationships between growth zones and mineral inclusions than zircon, hampering the correlation of age to metamorphism. To overcome this problem garnet–monazite trace element partitioning was determined for the first time, which can be used in future studies to relate monazite formation to garnet growth.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology letters 220 (2003), S. 0 
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The adaptive responses of the bacterium Acinetobacter calcoaceticus to different aliphatic alcohols on the level of the membrane fatty acids were studied in detail. The toxicity of the aliphatic alcohols increased with an increasing hydrophobicity. As alcohols are known to increase the fluidity of the membrane they consequently should cause the same adaptive effect on membrane level. Yet, cells of A. calcoaceticus react completely different to the alcohols: in the presence of long-chained alcohols they increase their degree of saturation, while in the presence of short-chained alcohols they decrease the degree of saturation. So, there are no observable differences in the adaptive responses of bacteria with the so-called anaerobic pathway, like Escherichia coli and Pseudomonas putida, and the bacterium carrying the so-called aerobic pathway like A. calcoaceticus. These results strongly indicate a physico-chemical difference in the membrane effect of both the partitioning and localisation of the different alcohols into the membrane and the membrane adaptive responses of the bacteria to these effects.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    British journal of dermatology 149 (2003), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background  Excimer laser-derived 308-nm ultraviolet (UV) B therapy is a new alternative for treating psoriasis by phototherapy. Some studies have been made showing the effectiveness of intralesional phototherapy technology in treating psoriasis. However, there has been no information available so far with regard to the cumulative dosage on a larger group of patients and on therapy optimized treatment strategies.Objectives  One hundred and twenty psoriatic patients were treated according to standard protocol to define the effectiveness. Our aim was to develop new parameters and determine whether effectiveness could be improved and whether treatment exposure, the cumulative UVB dose and adverse effects could be minimized.Methods  Initially, the excimer laser's effectiveness in treating psoriasis was evaluated in an open prospective study according to standard protocol. This included 120 adult patients (67 female/53 male) with chronic plaque psoriasis and 〈 20% involved body surface. The initial dose was based on three multiples of a predetermined minimal erythema dose (MED). Patients were treated twice a week for the first 3 weeks, then once a week until clearance was achieved. The main parameters were the initial starting dose, psoriasis area and severity index (PASI), the number of treatments needed, the time in treatment and the cumulative dose needed to clear psoriatic plaques. Thereafter, 43 patients were treated as a second comparable group. Therapy began with a starter dose, defined as MED-I. MED-I was defined as a UVB 308-nm dose which provoked a visible increase in erythema after 24 h. In addition, the epidermal thickness of the plaques was measured on an individual basis by 20-MHz ultrasound and correlated to the MED-I.Results  Of the patients who met the standard protocol, 65·7% were at least 90% clear after a maximum of 10 treatments; an even greater number (85·3%) showed a ≥ 90% improvement in PASI after 13 sessions, while 14·7% of patients had only a ≤ 50% PASI improvement. The cumulative UVB dose was 11·25 ± 4·21 J cm−2 and the average treatment time was 7·2 weeks. Patients treated individually with the MED-I starter dose showed nearly identical rates of clearance (83·7%), but were clear in 7·07 ± 2·15 sessions with a cumulative dose of 6·25 ± 4·02 J cm−2.Conclusions  The majority of our patients benefited greatly from laser-derived 308-nm UVB therapy, which cleared skin lesions faster than conventional phototherapy. As this therapy targets only the involved skin, the thickness of the plaques and individual MED-I should determine the initial dose, thus increasing the effectiveness of the therapy. We propose that light therapy sparing uninvolved skin will become predominant in the future.
    Type of Medium: Electronic Resource
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  • 4
    facet.materialart.
    Unknown
    Washington, etc. : Periodicals Archive Online (PAO)
    Germanic Review. 21:3 (1946:Oct.) 165 
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  • 5
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Isomerization of cis to trans unsaturated fatty acids is a mechanism enabling Gram-negative bacteria belonging to the genera Pseudomonas and Vibrio to adapt to several forms of environmental stress. The extent of the isomerization apparently correlates with the fluidity effects caused, i.e. by an increase in temperature or the accumulation of membrane-toxic organic compounds. Trans fatty acids are generated by direct isomerization of the respective cis configuration of the double bond without a shift of its position. The conversion of cis unsaturated fatty acids to trans is apparently instrumental in the adaptation of membrane fluidity to changing chemical or physical parameters of the cellular environment. Such an adaptive mechanism appears to be an alternative way to regulate membrane fluidity when growth is inhibited, e.g. by high concentrations of toxic substances. The cis–trans isomerase (Cti) activity is constitutively present and is located in the periplasma, it requires neither ATP nor any other cofactor such as NAD(P)H or glutathione, and it operates in the absence of de novo synthesis of lipids. Its independence from ATP is in agreement with the negative free energy of the reaction. cti encodes a polypeptide with an N-terminal hydrophobic signal sequence, which is cleaved off during or shortly after the enzyme is transported across the cytoplasmic membrane to the periplasmic space. A functional heme-binding site of the cytochrome c-type was identified in the predicted Cti polypeptide and very recently, direct evidence was obtained that isomerization does not include a transient saturation of the double bond.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Peptide methionine sulphoxide reductase (MsrA) and glutathione S-transferases (GSTs) are considered as detoxification enzymes. In the xenobiotics-degrading bacterium Ochrobactrum anthropi the two enzymes are co-induced by toxic concentrations of aromatic substrates such as phenol and 4-chlorophenol. In aerobic organisms, degradation of aromatic substrates by mono- and dioxygenases leads to a generation of oxidative stress that causes the occurrence of reactive oxygen species (ROS). A capillary electrophoretic method, using the intracellular conversion of dihydrorhodamine-123 into rhodamine-123, was developed to measure the content of ROS in the bacteria. The presence of toxic concentrations of the aromatic substrate 4-chlorophenol, an inducer of GST and MsrA, leads to a significant increase in the production of ROS. These results strongly suggest that GST and MsrA enzymes are part of the bacterial defence mechanism against particular oxidative stress conditions. As oxidative stress is known to be present predominantly close to the cytoplasmic membrane, we investigated the subcellular distribution of both MsrA and GST enzymes in this bacterium grown in the presence of 4-chlorophenol. By Western blotting, MsrA and GST was assayed in the cytoplasm as well as in the periplasm. Moreover, immunolocalisation by colloidal gold immunoelectron microscopy identified the two proteins associated with the cell envelope.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-0533
    Keywords: Key words Allograft-inflammatory factor-1 ; Microglia response factor-1 ; Macrophage-inhibiting factor ; related-protein-8/S100A8 ; Traumatic brain injury ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Intracellular calcium (Ca2+) has been shown to function as second messenger and to be associated with activation of different cell types including microglia. Previously, in human focal cerebral infarctions an early expression of macrophage-related protein-8 (MRP8/ S100A8), a member of the Ca2+-binding S100-protein family, in microglia has been reported. On the other hand, a delayed activation of microglia was observed following traumatic brain injury (TBI). We therefore examined immunohistochemically microglial expression of MRP8 and allograft inflammatory factor-1 (AIF-1), identical to microglial response factor-1 (mrf-1) and ionized calcium binding adaptor molecule-1 (iba1) in human brains after TBI and in control brains. Both, MRP8 and AIF-1 are Ca2+-binding peptides which have been associated with microglial activation in experimental models and in human cerebral infarctions. Detection of AIF-1 in controls confirmed constitutive expression of this peptide in a subset of microglial cells. After TBI, the density of AIF-1+ microglia did not increase significantly. Lesional expression of AIF-1 did not significantly differ from other brain regions. Furthermore, following TBI, we found no significant differences in the density of AIF-1+ microglia as compared to controls. Microglial MRP8 expression was not detectable in controls and within the first 3 days post TBI, but increased rapidly after 3 days post TBI, suggesting a subpopulation of microglial cells to be AIF-1–/MRP8+. We conclude that the delayed expression of MRP8 and the lack of AIF-1 up-regulation in microglia after TBI is in contrast to ischemic brain lesions and might reflect different activation cascades of microglia.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Annales geophysicae 18 (2000), S. 994-994 
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    European archives of psychiatry and clinical neuroscience 181 (1948), S. 256-274 
    ISSN: 1433-8491
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Zusammenfassung Es werden elektro-encephalographische Veränderungen bei Kranken gefunden, die an Anfällen nach Art der „synkopalen vasomotorischen Anfälle“ (Schulte) leiden. Diese Veränderungen bestehen vorwiegend in einer bei mäßiger Hyperventilation in den ersten Minuten zu beobachtenden Verlangsamung der Abläufe unter gleichzeitiger Zunahme der Amplituden, nachdem vorher meist eine immer deutlicher werdende Dysrhythmie auftritt. Gleichartige Veränderungen finden sich auch im Intervall bei Tetanien. Sie sind von den Intervallveränderungen der Epileptiker kaum zu unterscheiden. Daß das Gehirn, sogar die Rinde, bei diesen Krankheitsformen beteiligt ist, wird durch die EEG-Befunde bewiesen. Über seine ätiologische Rolle ist dagegen nichts Positives auszusagen.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    European archives of psychiatry and clinical neuroscience 181 (1949), S. 666-682 
    ISSN: 1433-8491
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Zusammenfassung Beim Hyperventilationsversuch kommt es zu einer Reihe von Änderungen im Stoffwechsel. Vor allem wird durch vermehrtes Abatmen von Kohlensäure im Säure-Basenhaushalt eine Verschiebung nach der alkalischen Seite herbeigeführt. Eigene Untersuchungen zeigen: 1. Ein Einfluß der Hyperventilation auf die Dauer des Kammeraktionsstroms im Ekg, die bei der Tetanie verlängert ist, wird bei gesunden Personen nicht gefunden. 2. Hyperventilationsveränderungen im Elektrencephalogramm — insbesondereδ-Wellen — sind normalerweise sowohl vom Alter der Versuchsperson wie auch von Art und Dauer der Hyperventilation abhängig. Bei einer Reihe von krankhaften Vorgängen (z. B. bei Epilepsie, bei Tetanie und bei vegetativen Krisen) können sie schon bei mäßiger Hyperventilation in den ersten Minuten auftreten. 3. Personen, die bei Hyperventilation sehr früh und sehr deutlich mit subjektiven und objektiven Erscheinungen reagieren, sind im Ertragen des plötzlichen Sauerstoffmangels in der Regel gegenüber anderen Personen benachteiligt, die bei Hyperventilation kaum ansprechen. In diesem Zusammenhang wird die Frage derätiologischen Bedeutung der Hypoxämie für die Genese verschiedener Erkrankungen diskutiert. 4. Alkalireservebestimmungen vor und nach Hyperventilation bei Personen, die dabei tetanisch reagierten, werden mit Alkalireservebestimmungen bei nichttetanisch reagierenden Versuchspersonen verglichen. Hyperventilation bringt regelmäßig ein starkes Ansteigen der Alkalireserve mit sich; ein sicherer Unterschied ist bei den beiden Personengruppen nicht festzustellen. Aus den eigenen Untersuchungen wird geschlossen, der Hyperventilationsversuch stelle eine Funktionsprüfung dar, auf die in erster Linie Systeme mit erhöhter Empfindlichkeit gegen Verschiebungen der Blutgasspannung ansprechen. Seine Erscheinungen sind zum größten Teil befriedigend durch eine Steigerung der allgemeinen Erregbarkeit erklärbar. Es bestehen Gründe für die Annahme, bei willkürlicher Hyperventilation spielten reflektorische Einflüsse — außer den geschilderten — eine Rolle; zu dieser Frage konnten eigene Untersuchungen nicht durchgeführt werden.
    Type of Medium: Electronic Resource
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