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101.
The determination of enzymatic activities in cell-free extracts of Acidaminococcus fermentans and Peptostreptococcus asaccharolyticus led to a refined scheme for the pathway of glutamate fermentation via (R)-2-hydroxyglutarate to acetate and butyrate. From the ratio of these products the amount of ATP generated by substrate level phosphorylation was calculated. Growth experiments with the organisms including Clostridium symbiosum and Clostridium tetanomorphum indicated that a sodium gradient contributed additional energy for growth. The high growth yields found in organisms containing the biotin dependent sodium pump glutaconyl-CoA decarboxylase could be reduced by the sodium ionophor monensin. In P. asaccharolyticus energy equivalent up to 0.6 mol ATP per mol of glutaconyl-CoA decarboxylated was conserved via the Na+ gradient. The data may explain the growth promoting effects of monensin in cattle. 相似文献
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104.
Mariann Thymann Bernadette Hoste Wolfgang Scheffrahn Jacques Constans Hartwig Cleve 《Human genetics》1985,69(3):224-227
Summary The proteins of three anodal Gc1 variants, Gc 1A16, 1A11, and 1A17, are characterized by the most acidic isoelectric points observed so far among the different Gc mutants. Stepwise removal of N-acetylneuraminic acid (NANA) by treatment with neuraminidase was performed to estimate the degree of sialilation of these Gc variants. The results indicate that both proteins, the anodal and the cathodal component of these Gc 1 mutants, carry sialic acid residues. This observation is remarkable in so far as usually only the anodal component of the Gc 1 protein contains NANA and only a single residue. From the experiments carried out it can be deduced that Gc 1A16 has two NANA residues in the anodal and one NANA residue in the cathodal component. Gc 1A16 was found in four members of three generations in a Danish family; the variant segregated as a Mendelian trait. More difficult to interprete are the results obtained with the variants Gc 1A11 and Gc 1A17. Gc 1A11 probably has three NANA residues in the anodal and two NANA residues in the cathodal component. Gc 1A11 has been observed in two mother-child pairs and is presumably also a simple genetic trait. Gc 1A17 has also several NANA residues in both Gc proteins; it is suggested that the anodal component has either three or four NANA residues and the cathodal component either two or three NANA residues. Family information on this variant is not yet available. 相似文献
105.
In an attempt to relate karyotype evolution to clinical and hematological data serial chromosomal analyses were performed in 31 patients with chronic myeloid leukemia (CML), both in chronic and acute phases. Our results in Philadelphia chromosome (Ph1)-positive CML are in line with karyotype profiles described in the literature. In addition, we report on chromosomal findings in 4 cases of Ph1-negative disease, one presenting with an iso17q chromosome in the positive CML. The same chromosomal abnormality was observed in a small population of Ph1-negative cells present in one of two patients with mixed Ph1-positive/Ph1-negative CML. The first case of a female patient with the loss of a sex chromosome in Ph1-positive cells is reported. Two patients with unusually long and mild chronic phases despite the presence of trisomy 8 in their karyotypes are described. Our findings suggest that the order of appearance of additional chromosomal changes of CML is of prognostic significance for the progression and the clinical picture of the disease. 相似文献
106.
G S Haas E Halperin D Doseretz R Linggood P S Russell R Colvin L Barrett A B Cosimi 《Journal of immunology (Baltimore, Md. : 1950)》1984,132(2):1026-1030
To better understand the immunologic effects of lymphoid irradiation (LI), blood levels of T cell subsets were sequentially monitored in 15 patients before, during, and after irradiation treatment for Hodgkin's disease. Blood levels of all lymphocytes, T cells, and T cell subsets (defined by OKT4 and OKT8) fell dramatically and in similar proportions during early therapy, reaching levels less than 20 to 25% of control by the completion of mantle irradiation, and continuing at very depressed levels through the completion of therapy. Blood levels of OKT8-reactive (OKT8+) cells returned to pretreatment levels (402 +/- 38/mm3 vs 360 +/- 32/mm3 pretreatment) between 6 to 8 mo after LI, whereas blood levels of OKT4-reactive (OKT4+) cells returned to only 42% of previous values (242 +/- 22/mm3 vs 584 +/- 34/mm3 pretreatment) over the same period. The pre-LI ratio of OKT4+ to OKT8+ cells was 1.85 +/- 0.24 and fell to 0.65 +/- 0.05 between 6 to 8 mo after LI. During the recovery period, discrepancies of 208 +/- 32 cells/mm3 (3 to 5 months post LI) and 198 +/- 32 cells/mm3 (6 to 8 mo post LI) developed between the blood levels of OKT3+ cells and the sum of OKT4+ and OKT8+ cells. This suggests the emergence of OKT4+/OKT3-, OKT8+/OKT3-, and/or OKT4+/OKT8+ cells. In five patients, the sum of OKT4+ and OKT8+ cells was compared with the number of cells simultaneously co-stained by OKT4 and OKT8. It appeared that a significant proportion of the cells were OKT4+/OKT3- and OKT8+/OKT3- lymphocytes. We concluded that LI is similarly cytotoxic to peripheral blood T cell subpopulations. The reversed ratio after LI is a result of a slower repopulation of the peripheral blood by OKT4+ cells relative to OKT8+ cells. T cells after LI show a high degree of antigenic immaturity. It is postulated that the bone marrow that lies outside the fields of treatment and contains predominantly immature OKT8+/OKT3- cells is a major source of T cells repopulating the peripheral blood after LI. 相似文献
107.
Albrecht Guhlmann Wolfgang Hagmann Dietrich Keppler 《Prostaglandins & other lipid mediators》1987,34(1)
N-Acetyl-leukotriene E4, the end product of leukotriene C4 metabolism in the mercapturic acid pathway, was rapidly eliminated from the blood circulation into the bile of rats. Part of the N-acethyl-leukotriene E4 secreted from bile into the intestine undewent enterohepatic circulation. Leukotriene absorption occurred from the small intestine and from the colon. Biliary and urinary excretion within 5.5 h amounted to 15 and 2%, respectively, of the intraduodenally administered N-acetyl- H leukotriene E4 in animals anesthetized with ketamine. HPLC analyses indicated that 35% of the biliary radioactivity corresponded to unchanged N-acetyl- H leukotriene E4, while 65% in bile and 100% in urine were polar metabolites. Enterohepatic circulation extends the biological half-life of N-acetyl-leukotriene E4. 相似文献
108.
Dewsbury, D. A., ed. (1985): Foundations of comparative psychology (Zur Geschichte der vergleichenden Psychologie). Benchmark Papers in Behavior Series. Toates, F. (1986): Motivational systems (Antriebe). Le Magnen, J. (1986): Hunger. Rosenblatt, J. S., C. Beer, M.-C. Busnel, & P. J. B. Slater, eds. (1985): Advances in the study of behavior. Dickerson, J. W. T., & H. McGurk, eds. (1982): Brain and behavioural development. Interdisciplinary perspectives on structure and function (Gehirn und Verhaltensentwicklung). Bisping, R. (1985): Gedächtnisübertragung bei Goldfischen. Experimentelle Untersuchungen in der “shuttle-box” mit besonderer Berücksichtigung des Problems der Reizspezifität unter einer Rot-Grün-Diskriminationsbedingung (Memory transfer in goldfish). Nachtigall, W. (1984): Erfinderin Natur: Konstruktionen der belebten Welt (Natural constructions). Rasch und Röhring Verlag, Hamburg und Zürich. 相似文献
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Prof. Dr. med. Wolfgang Schulze Martin Riemer Uwe Rehder Karl-Heinz Höhne 《Cell and tissue research》1986,244(1):1-8
Summary With the use of a digital image-processing method three-dimensional reconstructions of the arrangement of spermatocytes in human seminiferous tubules were performed. With this method it was possible to investigate the cellular distribution in the tubule in nearly any given perspective and projection. In addition, by means of simple mathematical procedures, such as by transformation of Cartesian coordinates into cylindrical coordinates, it was possible to vary the shape of a reconstruction, i.e., to convert the cylindrical image of a tubular portion into a right-angled r--z-representation.The present work not only confirms the existence of a complex helical plan of organization of the human seminiferous epithelium but also provides further aspects of the phenomenon of physiological germ-cell loss and its integration into the kinetics of spermatogenesis.Dedicated to Prof. E.C. Roosen-Runge, Seattle, on the occasion of his 75th birthday 相似文献