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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 47 (1969), S. 49-57 
    ISSN: 1432-1440
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Red cell precursors was investigated by means of Feulgen-photometric measurements in the bone marrow from 7 haematological normal persons, 2 patients with acute bleeding, 9 patients with haemolytic anaemia, 6 patients with iron-dificiency anaemia, 6 patients with polycythaemia, 4 patients with pancytopenia, 5 patients during bone marrow regeneration of agranulocytosis and 9 patient with megaloblastic anaemia. 1. 2/3 of red cell precursors shows 2n (2c) DNA-values in normal bone marrow. The other cells are in DNA-synthesis, or they have already doubled their premitotic DNA-content before the onset of mitosis. We have never found erythroblasts with 6n (6c) or 8n (8c) DNA-values. 2. The percentage of DNA synthesizing cells calculated by Feulgen-photometry corresponds to the labelling index by means of3H-thymidine-autoradiography. 3. Disturbances in erythropoiesis in the course of acute bleeding, acute haemolysis, drug induced allergic bone marrow insufficiency and in the course of regeneration of megaloblastic bone marrow after vitamine B12 injection leads to acute changes in the percentage of cells in DNA-synthesis. No changes of the percentage of red cell precursors in DNA-synthesis takes place in cases of prolonged bone marrow irritation in persistent haemolytic anaemia and in polycythaemia. Augmentation of the erythropoietic active bone marrow restored the additional required erythrocytes in these diseases. A diminution of active bone marrow cells and a decrease of DNA synthesizing cells are findings in pancytopenia. 4. A distinct augmentation of red cell precursors with a DNA-content in the middle of 2n and 4n (2c–4c) values in megaloblastic anaemia points at an inhibition of DNA-synthesis in the middle of the DNA synthesis period or of cell death before completion of DNA replication (as a sign of ineffective erythropoiesis). 5. An increase of red cell precursors with 4n (4c) DNA-values in the G2-period of generation cycle takes place after treatment with32P, in megaloblastic anaemia and in anaemia in Glutathionreductase deficiency. This augmentation of G2-cells is not caused by an increase of DNA synthesizing cells. It indicates therefore a prolongation of G2-period and an inhibition of onset of mitosis.
    Notes: Zusammenfassung Es wurden Ergebnisse feulgenphotometrischer DNS-Bestimmungen an roten Vorstufen des Knochenmarks bei 7 hämatologisch Gesunden, 2 Patienten mit frischer Blutung, 9 Patienten mit einer hämolytischen Anämie, 4 Patienten mit einer Eisenmangelanämie, 6 Patienten mit einer Polycythaemia vera bzw. Polyglobulie, 4 Patienten mit einer Pancytopenie, 5 Patienten im Ablauf einer medikamentös allergischen Agranulocytose und 9 Patienten mit einer megaloblastären Anämie vorgelegt. 1. Im Knochenmark hämatologisch Gesunder weisen rund 2/3 der roten Vorstufen annähernd 2n- bzw. 2c-DNS-Werte auf. Der Rest der Zellen befindet sich in prämitotischer DNS-Synthesephase oder hat bereits vor Eintritt in die neue Mitose den DNS-Gehalt verdoppelt. Bei keinem der untersuchten Patienten ließ sich ein Erythroblast mit einem 6n- oder 8n-DNS-Gehalt nachweisen. 2. Der nach quantitativen DNS-Bestimmungen errechnete prozentuale Anteil in DNS-Synthese befindlicher roter Vorstufen entspricht den Ergebnissen nach3H-Thymidininkubation. 3. Akute Störungen innerhalb der Erythropoese infolge einer frischen Blutung, eines akuten hämolytischen Schubes, einer medikamentös-allergisch ausgelösten Markschädigung oder durch eine Markumwandlung nach hochdosierter Gabe von Vitamin B12 im B12-Mangelzustand führen vorübergehend zu einer Änderung des Zellanteils in DNS-Synthese. Länger andauernde Störungen (persistierende hämolytische Anämie, Polycythaemie, Polyglobulie) weisen jedoch gegenüber der normalen Erythropoese keine Zeichen einer veränderten Zellregeneration auf. Der Mehrbedarf an Erythrocyten dürfte in diesen Fällen durch die Ausdehnung des erythropoetisch aktiven Knochenmarks gedeckt werden. Bei Pancytopenien findet sich neben einer Verkleinerung der Gesamtzellzahl im Knochenmark eine Verminderung DNS-synthetisierender Zellen. 4. Eine umschriebene Häufung roter Vorstufen mit einem DNS-Gehalt in der Mitte zwischen 2n- und 4n-Werten weist bei megaloblastären Anämien auf einen verlangsamten Ablauf der DNS-Synthese bzw. auf einen Untergang einzelner roter Vorstufen während der DNS-Verdoppelungsphase im Sinne einer ineffektiven Erythropoese hin. 5. Als Besonderheit fällt nach Radiophosphorbehandlung und bei megaloblastären Anämien wie bei Anämie infolge Glutathionreductasemangel eine Vermehrung der Zellen mit verdoppeltem (4n)-DNS-Gehalt (G2-Phase) auf. Da dieser Befund nicht durch eine Zunahme DNS-Synthetisierender Zellen und damit einen vermehrten Eintritt der Zellen in die G2-Phase erklärt werden kann, muß eine Verlängerung der G2-Phase und ein verzögerter Mitosebeginn angenommen werden.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Manuscripta mathematica 96 (1998), S. 181-194 
    ISSN: 1432-1785
    Keywords: Mathematics Subject Classification (1991):31B05, 41A63, 41A50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract: Let , where B is the open unit ball in ( ), and let denote the collection of functions h in which are harmonic on B and satisfy on . A function h * in is called a best harmonic one-sided L 1-approximant to f if for all h in . This paper characterizes such approximants and discusses questions of existence and uniqueness. Corresponding results for approximation on the cylinder are also established, but the proofs in this case are more difficult and rely on recent work concerning tangential harmonic approximation. The characterizations are quite different in nature from those recently obtained for harmonic L 1-approximation without a one-sidedness condition.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Numerische Mathematik 15 (1970), S. 165-174 
    ISSN: 0945-3245
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary This paper is concerned with convergence of interpolation polynomials in two variables. Some investigations have been made in the special cases of Lagrange and Fejér-Hermite interpolation. Here we give a general method to prove convergence of two-dimensional interpolation processes. The theory is based on the concept of tensor products of interpolation problems. Our main theorem shows that a two-dimensional interpolation process which is a tensor product of two one-dimensional processes converges for a functionh єC [a, b] ⊗C [ā, b] if both “factors” do for certain one-dimensional functions. In addition we prove how the order of convergence of the two-dimensional process depends on the one-dimensional processes. The converse theorem is not true. But we can give a sufficient condition which depends on the density of the interpolation nodes to assure the converse theorem in some cases. In an easy manner the convergence theorem may be extended to higher dimensions.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Tetrahedron Letters 7 (1966), S. 2217-2220 
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Tetrahedron Letters 6 (1965), S. 1753-1755 
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Tetrahedron Letters 7 (1966), S. 5401-5404 
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Tetrahedron Letters 6 (1965), S. 2328 
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Summary Poly-N-carbonyl- and Poly-N-sulfonyl-guanidines were prepared by interfacial polycondensation of N-Dichloromethylenecarbonicacid-amides and N-Dichlor-methylene-sulfonicacid-amides respectively with diamines. The viscosities and softening points of the polymers were determined. Their IR-spectra were compared with those of low molecular weight modell compounds.
    Notes: Zusammenfassung Poly-N-carbonyl- und Poly-N-sulfonyl-guanidine wurden durch Zwischenphasenpolykondensation aus N-Dichlormethylen-carbonsäureamiden bzw. N-Di-chlormethylen-sulfonamiden und Diaminen hergestellt. Die Viskositäten und Erweichungsbereiche der Polymeren wurden bestimmt und ihre IR-Spektren mit entsprechenden niedermolekularen Modellverbindungen verglichen.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Archiv der Mathematik 75 (2000), S. 125-131 
    ISSN: 1420-8938
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract. Let $f \in C^{1,1} ([-1,1]^2), \partial ^2f/\partial x \partial y \geqq 0$ . We characterize the unique best one-sided L 1-approximant h * to f from above (resp. h * from below) with respect to the subspace B 1,1 which consists of all bivariate functions which are sums of univariate functions. h * resp. h * are constructed by a Hermite type interpolation on the diagonal $\{ (t,t) : t \in I \} $ resp. the anti-diagonal $\{ (t,-t) : t \in I \} $ , where $I := [-1,1]$ .
    Type of Medium: Electronic Resource
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