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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 5045-5050 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Various processing routes for making permanent magnets based on interstitially modified Sm2Fe17 have been recently developed. Zn bonding of coarse grained Sm2Fe17N3 gives coercivities μ0JHc as high as 2.2 T. Effective methods to prepare highly coercive Sm2Fe17N3 powders for polymer bonding are mechanical alloying and rapid quenching. With the very simple method of additional milling of coarse grained nitrided powders we achieved μ0JHc≈1.5 T. A coercivity up to 3.5 T has been achieved by a modified HDDR procedure, reducing the particle size of the starting material by milling prior to the hydrogenation–disproportionation–desorption–recombination (HDDR) treatment. This is attributed to a better control of two critical parameters, namely grain size and the amount of unrecombined α-Fe accompanying the intermediate TbCu7 structure-type phase. Resin bonded HDDR-Sm2Fe17N3 magnets show an unexpected high initial susceptibility. This may be due to a strong magnetic interaction of the grains. To develop coercivity in Sm2Fe17Cy(approximately-greater-than)1 obtained by gas–solid reactions of Sm2Fe17 the same methods as those applied to Sm2Fe17N3 can be successfully used. Fully dense magnets with a coercivity up to 1.5 T were made from the interstitially as well as substitutionally modified compound Sm2Fe15Ga2C2 by hot pressing of highly coercive powders. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 129-131 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thermodynamically stable nanocrystalline Sm2Fe15Ga2C2 powders were prepared by intense ball milling of homogenized and coarsely ground ingots, and a subsequent annealing of the powders in an argon atmosphere. Such processing results in magnetically isotropic material with a room-temperature coercivity μ0JHc of up to 1.2 T. Scanning electron microscopy observations suggest a homogeneous microstructure, and combined with Scherrer formula estimations, an average grain size of 〈100 nm has been determined. The coercivity can be preserved at high annealing temperatures when the process is performed at an argon pressure of about 800 mbar. The attempt of a hot-pressing procedure resulted in a magnet with a density of 86% (6.7 g/cm3) of the theoretical density (7.8 g/cm3) and a coercivity of 1.3 T. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Pediatric allergy and immunology 7 (1996), S. 0 
    ISSN: 1399-3038
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Age related differences in immunological reactions include variations in the in vitro functions of blood mononuclear cells (MNC). In an attempt to understand the mechanism behind these differences we examined age related differences in the phenotype profiles of MNC in parallel with the in vitro production of interleukin IL-6, tumour necrosis factor alpha (TNFα) and in-terferon gamma (IFNg) in neonates, children and adults. In cultures without added polyclonal activators IL-6 and TNFα levels in children were 3–6 times higher than those of umbilical cords and adults. However, using optimal in vitro stimulation (E. coli lipopolysaccharide (LPS), phytohaemmag-glutinin or pokeweed mitogen (PWM)) no significant differences in the levels of these cytokines were observed. The levels of IFNg in PWM driven cultures followed a different pattern with comparable levels in children and adults, and unmeasurable levels in cord blood MNC. Flow cytometry analysis of the phenotypic distribution of MNC revealed age related differences in the expression of CD3, CD4, CD8, CD14, CD19, CD45RA, CD45RO, CD2, LFA-1, ICAM-1 and LFA-3. Correlation studies did not indicate that the observed differences in cytokine production could be ascribed to differences in the frequency of monocytes, T cells or B cells. The TNFα levels in suboptimally stimulated cultures correlated negatively with the expression of LFA-3 and positively with CD45RA. while IFNg correlated positively with CD2, LFA-1, CD45R0 and CD8.In conclusion, the study provides evidence of age related differences in the production of TNFα, IL-6 and IFNg among neonates, children and adults. These differences may to some extent be caused by differences in the expression of cell surface molecules involved in cellular interactions and signalling.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 381 (1996), S. 676-678 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] In 1983, Hock et al6 studied Jahn-Teller (JT) ions in a conductor within a linear chain model. They showed that a small JT polaron (the combination of the electron and induced lattice distortion around it) can be formed when the JT stabilization energy is comparable with the bare conduction ...
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 235-238 (Oct. 1996), p. 801-806 
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 242 (Dec. 1996), p. 91-100 
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Monatsschrift Kinderheilkunde 144 (1996), S. 1214-1217 
    ISSN: 1433-0474
    Keywords: Schlüsselwörter Kongenitale Alveolarproteinose ; Surfactantprotein B ; Gendiagnostik ; Key words Congenital alveolar proteinosis ; Surfactant protein B deficiency ; Genetic diagnostics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary A term female neonate born to healthy, unrelated parents developed signs of respiratory distress shortly after birth, requiring intubation and mechanical ventilation with high inspiratory oxygen concentrations. The chest X-ray showed diffuse reticular opacities with predominance in the more central areas. Neither exogenous surfactant therapy or systemic steroids had any effect. An open lung biopsy suggested alveolar proteinosis. Surfactant analyses in broncho-alveolar lavage and genetic investigations in the patient and her parents helped to establish the diagnosis of congenital surfactant protein B deficiency. The patient died of respiratory failure at 8 weeks of age. In congenital surfactant protein B deficiency, mutations in the SFTP3-gene on chromosome 2 (which encodes SP-B) result in a disturbance in both surfactant homeostasis and -function which is not amenable to therapy. In families where such mutations are known, e. g. the 121ins2 mutation, the diagnosis can already be established antenatally.
    Notes: Zusammenfassung Wir berichten über ein reifes weibliches Neugeborenes mit unauffälliger Familienanamnese, das wenige Stunden postpartal mit einer Tachydyspnoe und zunehmender Zyanose auffällig wurde, so daß Intubation und maschinelle Beatmung mit hohen Sauerstoffkonzentrationen erforderlich wurden. Radiologisch zeigte sich eine zentralbetonte, diffus vermehrte retikuläre Zeichnung beider Lungen. Weder die Gabe von exogenem Surfactant noch eine systemische Steroidtherapie brachten eine Verbesserung der respiratorischen Situation. Eine Lungenbiopsie ergab den Verdacht auf das Vorliegen einer Alveolarproteinose. Mittels Surfactantanalysen in der Bronchiallavage und genetischer Untersuchungen des Kindes und seiner Eltern konnte die Diagnose einer durch einen kongenitalen Surfactant-Protein-B-Mangel bedingten Alveolarproteinose gesichert werden. Das Kind verstarb im Alter von 8 Wochen an seiner respiratorischen Insuffizienz. Beim angeborenen Surfactant-Protein-B-Mangel kommt es aufgrund von Mutationen im für die Kodierung dieses Proteins verantwortlichen SFTP3-Gen auf dem Chromosom 2 zu einer therapierefraktären Störung der Surfactantfunktion und -homöostase. Ist die verantwortliche Mutation bekannt, wie z. B. bei der 121ins2-Mutation, die bei unserer Patientin vorlag, so kann bei weiteren Schwangerschaften die Diagnose dieser autosomal-rezessiv vererbten Erkrankung bereits pränatal erfolgen.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1432-2307
    Keywords: Bronchial preneoplastic lesions ; Neovascularization ; Factor VIII labelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Angiogenesis is important in a large number of normal and pathological processes including tumour growth and development, inflammation and in wound healing. We investigated whether neovascularization exists in hyperplastic, metaplastic and potentially preneoplastic lesions of the bronchial mucosa as prestages for lung cancer. Biopsy specimens from 86 patients were investigated light microscopically. Formalin-fixed and paraffin-embedded specimens of regular bronchial mucosa including epithelium, basement membrane zone and tunica propria (n=12) without inflammation were compared with specimens with inflammatory reaction (n=9), basal cell- and goblet cell hyperplasia (n=24), squamous cell metaplasia (n=9), squamous cell metaplasia with different degrees of dysplasia (n=11), specimens of micropapillomatosis (n=9) and 13 cases with carcinoma in situ. The grade of neovascularization was assessed by the microvessel density, which was obtained by an immunohistochemical staining of endothelial cells using factor VIII-related antigen and determined by an automatic image-analysing-system. Microvessels were counted in selected areas of highest neovascularization on a×100 field 0.4 mm underneath the basement membrane zone in the tunica propria. Microvessel count, minimal and maximal diameter of the vessels were chosen as morphological variables. A significantly increased microvessel count with 33 vessels/0.6 mm2 was found in specimens with inflammation of the tunica mucosa (regular bronchial mucosa: 20 vessels/0.6 mm2). Microvessel diameter (surface of cut section) increased in specimens of bronchial mucosa with inflammation to 11.3×10−4 mm2 (regular bronchial mucosa: 9.04×10−4 mm2). Microvessel count increased in cases of squamous cell metaplasia (33 vessels/0.6 mm2) squamous cell metaplasia with different degrees of dysplasia (50 vessels/0.6 mm2) and carcinoma in situ with 61 vessels/0.6 mm2. With increasing dysplasia, increasing neovascularization was found in close vicinity to the basement membrane zone. Simultaneously, interepithelial sprouts of endothelial cells were seen. Qualitative and quantitative differences were thus found in potentially preneoplastic lesions.
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  • 9
    ISSN: 1432-055X
    Keywords: Schlüsselwörter Kinder der Zeugen Jehovas ; Anämie ; Verbrennung ; Erythropoetin ; Key words Children of Jehovah's witnesses ; Burn injury ; Anaemia ; Erythropoietin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract A 3.5-year-old girl suffered from a thermal injury affecting 37% of the body surface area. The parents, being Jehovah's witnesses, refused permission for their child to receive blood transfusions. As the haemoglobin level was only 7.5% and a necrectomy was planned, the patient was likely to need blood transfusions. Indications for transfusion were defined as clinical signs of hypoxia and/or cardiovascular instability. A judicial declaration was proposed. Hb decreased during the therapy. To stimulate the erythropoiesis erythropoietin and iron were administered. During the clinical course the anaemia worsened. First, a conservative treatment with polyvidoniodine ointment for tanning was started, to avoid an operation during the acute phase after the injury, as in this case it was thought a blood transfusion would definitely be necessary. On the 19th day after the injury a necrectomy of 10% of the body surface was necessary because of fever and leucocytosis not responding to antibiotics. The most likely cause of the symptoms was an infection of the burned area. Hb was 4.6 g/dl%. General anaesthesia was performed with midazolam, ketamine and vecuronium and mechanical ventilation. No blood transfusion was required during the operation.Vital signs were stable during the preoperative period, during anaesthesia and following the operation. There were no signs of tissue hypoxia. Peripheral oxygen saturation ranged between 98% and 100%, lactate and arterial blood gas samples were normal, and the child was awake and cooperative before and after anaesthesia. The lowest Hb was 3.3 g/dl on the 22th day after injury (3rd postoperative day). In this phase the patient was still playing and riding a tricycle. On the 45th day after injury the child was discharged home with Hb of 10.9 g/dl and reticulocytosis of 33%.
    Notes: Zusammenfassung Ein 3,5jähriges Mädchen, dessen Eltern als Zeugen Jehovas eine Bluttransfusion bei ihrem Kind kategorisch ablehnten, wurde mit einer Verbrennung von 37% der Körperoberfläche und einem Hb von 7,5 g/dl zur Operation verlegt. Als Transfusionsindikationen wurden für den stationären Aufenthalt klinische Zeichen einer Hypoxie und/oder Kreislaufinstabilität festgelegt. Es wurde eine richterliche Verfügung erwirkt, die den Eltern das Sorgerecht für die medizinischen Maßnahmen entzog, um ggf. bei oben beschriebener Indikation eine Transfusion durchführen zu können. Im Verlauf der Behandlung nahmen Hb und Hk weiter ab. Trotz Gabe von Erythropoetin und Eisen konnte die Erythropoese nicht stimuliert werden. Um eine Operation im Akutstadium zu vermeiden, die mit einer hohen Wahrscheinlichkeit eine Bluttransfusion erforderlich gemacht hätte, wurde primär eine konservative Therapie mit einer Gerbung durch Polyvidon-Jodsalbe durchgeführt. Aufgrund einer nekrosebedingten systemischen Infektion erfolgte am 19. Tag eine Nekrosektomie von ca. 10% der Körperoberfläche mit Deckung durch Eigenhaut vom Unterschenkel in intravenöser Anästhesie und kontrollierter Beatmung (Ketamin/Midazolam/Vecuronium). Der Hb betrug präoperativ 4,6 g/dl, der Hk 14%. Da das Kind während des gesamten stationären Aufenthalts kreislaufstabil war und keine Zeichen einer Hypoxie auftraten, wurde keine Transfusion durchgeführt. Der niedrigste Hb betrug am 22. Tag nach Unfall (=3. postoperativer Tag) 3,3 g/dl. Am 45. Tag nach Unfall wurde das Kind mit einem Hb von 10,9 g/dl und 33% Retikulozyten im Differentialblutbild nach Hause entlassen.
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  • 10
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Functional bivalent miniantibodies, directed against the epidermal growth factor receptor, accumulated to more than 3 gl−1 in high-cell-density cultures of Escherichia coli RV308(pHKK) on a pilot scale. The miniantibodies consist of scFv fragments with a C-termi-nal hinge followed by a helix-turn-helix motif, which homodimerizes in vivo. The improved expression vector pHKK is characterized by the hok/sok suicide system, improving plasmid maintenance, and the inducible lac p/o promoter system with the very strong T7g10 Shine-Dalgarno sequence. The expression unit is flanked by terminators. The prototrophic RV308 cells were cultivated in glucose mineral salt medium and reached a cell density of 145 g dry biomass l−1 after 33 h. After induction, growth continued almost unchanged for a further 4 h with concomitant miniantibody formation. In the fed-batch phase, the concentration of glucose was kept almost constant at the physiological level of approximately 1.5 g l−1, using on-line flow injection analysis for control. Surprisingly, E. coli RV308(pHKK) did not accumulate significant amounts of the metabolic by-product acetate under these unlimited aerobic growth conditions.
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