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  • 1
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Platinum group elements (PGE) are strategic materials because 96–99% of the world production is derived from just five mining districts and because they cannot be replaced as catalysts in many chemical processes. In order to lessen the strategic character of PGE, both conventional deposits and unconventional PGE mineralizations were investigated in an attempt to locate viable deposits which would diversify the supplier base. In the Great Dyke, conventional PGE mineralization occurs in the form of pristine sulfide ores mined underground and oxidic surface ores. New observations such as bimodal distributions of the PGE in the Main Sulfide Zone (MSZ), elevated Pt/Pd ratios in the oxidized MSZ compared to the sulfidic part and distinct differences between the platinum group mineral (PGM) assemblages of the MSZ and stream sediments of adjacent rivers emphasize the fact that even though the Great Dyke seems to be the second or third largest PGE occurrence in the world, the complicated PGE distributions and supergene redistributions should be kept in mind during planning and mine operation. Investigations of unconventional PGE occurrences in ophiolites, Alaskan-type intrusions, porphyry copper deposits and in the Kupferschiefer show that economically exploitable PGE concentrations can be expected in a broader variety of host rocks than considered favourable in the past. In the Albanian Mirdita ophiolite average contents of 860 ppb Pt and 60 ppb Pd were detected. Flotation concentrates of porphyry copper deposits, for example from Mamut, Malaysia, Santo Tomas, Philippines, Elacite, Bulgaria, and Ok Tedi, Papua New Guinea, contain between 827 and 1860 ppb Pd + Pt. In selected profiles of the Polish Kupferschiefer average contents of 255 ppb Pt, 94 ppb Pd, 2.4 ppm Au and 13.0 ppm Ag were analysed. The distribution of the PGE resources in the world and the annual production rates, however, underline the fact that the chances for a significant change in the supplier base are relatively low. The Bushveld Complex will remain the largest producer, followed by Noril'sk-Talnakh, Sudbury and Stillwater. If the operations in the Great Dyke reach their planned capacities, the Great Dyke will rank in third place among the PGE-producing deposits in the world.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    International Journal of Psychophysiology 7 (1989), S. 185 
    ISSN: 0167-8760
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine , Psychology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Nuclear Instruments and Methods 182-183 (1981), S. 297-302 
    ISSN: 0029-554X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Physics
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Thin Solid Films 76 (1981), S. 259-267 
    ISSN: 0040-6090
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Nuclear Instruments and Methods 149 (1978), S. 73-76 
    ISSN: 0029-554X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Physics
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 46 (1990), S. 158-160 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 44 (1988), S. 1860-1861 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 44 (1988), S. 2226-2227 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    European journal of epidemiology 8 (1992), S. 321-325 
    ISSN: 1573-7284
    Keywords: Cryptococcus neoformans var. gattii ; Ecology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Environmental isolations have established that Cryptococcus neoformans var. gattii serotype B appears to have a specific ecological association with Eucalyptus camaldulensis. The global distribution of the tree appears to correspond to the epidemiologic distribution of cryptococcosis caused by C. neoformans var. gattii. The epidemiology of cryptococcosis can primarily be explained by exposure to an infective aerosolized inoculum, such as basidiospores released from specific host plants and/or desiccated blastoconidia (yeast cells) disseminated from accumulations of dried pigeon dung. The ecology of C. neoformans still remains largely unresolved, studies on the host-parasite interaction between serotype B and E. camaldulensis are still in progress, and extensive environmental searches are now underway to determine the natural habitats of serotypes A, C and D.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1433-0385
    Keywords: Key words: Aorta – Aneurysm – Aortic aneurysm – Aortic aneurysm, abdominal – Aortic aneurysm, abdominal surgery. ; Schlüsselwörter: Aorta – Aneurysma – Aortenaneurysma – abdominelles Aortenaneurysma – chirurgische Therapie.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung. Einleitung: Anfang der 90er Jahre kam die endovasculäre Stentimplantation als neuartige Methode zur Behandlung des abdominellen Aortenaneurysmas (AAA) auf. Dies bot uns Anlaß, die eigenen Ergebnisse der offenen Chirurgie des AAA zu überprüfen, um die Frage der Standardtherapie des AAA neu zu überdenken. Methoden: Die medizinischen Daten von 941 konsekutiven Patienten mit AAA, die in unserer Klinik von 1990–1997 offen chirurgisch behandelt wurden (Durchschnittsalter 67 Jahre, 6 % über 80 Jahre, 14,5 % Frauen, 3,2 % suprarenale AAA), wurden retrospektiv analysiert. 778 asymtomatische Patienten wurden elektiv, 104 symptomatische Patienten wurden dringlich, und 59 symptomatische Patienten (davon 45 mit Perforation) wurden als Notfall operiert. Ergebnisse: Die Letalität betrug bei elektiven Operationen 1,54 %, bei dringlichen Operationen 8,65 % und bei Notfällen mit perforiertem AAA (unverzügliche Operation nach Aufnahme in die Klinik) 35,6 %. Die Morbidität lag bei elektiven Eingriffen bei 15,9 %, bei dringlichen Operationen bei 28,8 % und bei Notfalloperationen mit perforiertem AAA bei 66,7 %. Für Patienten mit zusätzlichen Eingriffen an Nieren-, Becken- und Beinarterien sowie Kombinationseingriffen in anderen Operationsgebieten war die Letalität im Vergleich zum Durchschnitt nicht erhöht. Schlußfolgerung: Aufgrund der niedrigen Letalität und Morbidität stellt die offene Chirurgie auch heute den gültigen Standard der AAA-Behandlung dar.
    Notes: Summary. Introduction: In 1990 the new method of endovascular graft treatment of abdominal aortic aneurysms (AAA) emerged. For this reason we analyzed the results of open surgery for AAA in our department to consider the question of standard therapy. Methods: In a retrospective study the medical data of 941 consecutive patients treated by open surgery in a single center from 1990 to 1997 (mean age 67 years, 14.5 % female, 3.2 % suprarenal AAA) were analyzed. Operations were performed electively in 778 asymptomatic patients, urgently in 104 symptomatic patients, and as emergency operations (immediately after admission) in 59 symptomatic patients (45 patients presenting with rupture). Results: Mortality was 1.54 % (elective operations), 8.65 % (urgent operations), and 35.6 % (emergency operations, rupture). Morbidity was 15.9 % (elective operations), 28.8 % (urgent operations), and 66.7 % (emergency operations, rupture). Mortality was not increased in patients undergoing additional procedures of the renal, iliac, femoral, or crural arteries. Conclusion: Because of its low mortality and morbidity today open surgical repair remains the standard therapy for AAA.
    Type of Medium: Electronic Resource
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