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41.
Application of [ (14)C]-progesterone to the leaves of NERIUM OLEANDER L. (Apocynaceae) resulted in the formation of [ (14)C]-digitoxigenin and [ (14)C]-oleandrigenin glycosides; the labelled aglycones were obtained after hydrolysis from the cardenolide extract. Both radioactive cardenolide aglycones were further transformed by the leaves of NERIUM OLEANDER L. to the corresponding 3- O-beta-glucosides digitoxigenin glucoside and oleandrigenin glucoside. It could be shown that both cardenolide glucosides are genuine constituents of the cardenolide fraction of NERIUM OLEANDER L. leaves. The structures of these newly identified compounds were verified by (1)H-NMR and FAB (+) mass spectroscopy and by enzymatic cleavage of the glycosidic bond with a beta-glucosidase from HELIX POMATIA. 相似文献
42.
Franz Buchegger Mai Phan Denis Rivier Stephan Carrel Roberto S. Accolla Jean-Pierre Mach 《Journal of immunological methods》1982,49(2):129-139
A solid-phase enzyme immunoassay using both mouse monoclonal and goat polyclonal antibodies against carcinoembryonic antigen (CEA) was developed. The assay detects 0.6 to 1.2 ng of CEA per ml of serum and has 3 incubation steps which can be performed in 1 day. Polystyrene balls coated with polyclonal goat anti-CEA antibodies are first incubated with heat-extracted serum samples. Bound CEA is then detected by addition of mouse monoclonal antibodies, followed by goat IgG anti-mouse IgG1 coupled to alkaline phosphatase. Results with this enzyme immunoassay using monoclonal antibodiies (M-EIA) have been compared with those obtained by the conventional inhibition radioimmunoassay (RIA) using goat antiserum. Three hundred and eighty serum samples from 167 patients with malignant or non-malignant diseases and from 134 normal individuals with or without heavy smoking habits were analyzed by the 2 assays. Excellent correlation between the results of the 2 assays was obtained, but the M-EIA, using monoclonal antibodies from a single hybridoma, did not discriminate better than the conventional RIA between CEA produced by different types of carcinoma and between CEA associated with malignant or non-malignant diseases. Follow-up studies of several patients by sequential CEA determinations with the 2 assays showed that the M-EIA was as accurate as the RIA for the detection of tumor recurrences. 相似文献
43.
Franz Fogt Robert L Zimmerman Christopher J Hartmann Charlotte A Brown Navneet Narula 《International journal of molecular medicine》2002,9(1):59-60
Cardiac myxomas are the most frequent cardiac tumors and cause for significant morbidity and mortality. Recent evidence indicates that cardiac myxomas are, in fact, neoplasms rather than organized thrombi. Cardiac myxomas may present as solitary lesions or in association with the Carney complex. Carney complex has been linked to chromosome 2p16 and the PRKAR1A gene at 17q22-24. In this study, we analyzed sporadic cardiac myxomas to evaluate whether the genetic alterations seen in Carney complex are present in non Carney complex associated cardiac myxomas as well. We analyzed microdissected material from 13 patients with cardiac myxomas for the markers PRKAR1 9CA, D2S2153, D2S2251 and D2S123. None of the cases demonstrated loss of heterozygosity or definite band changes suggestive of microsatellite instability for any of the markers used. We conclude that sporadic cardiac myxomas are genetically not related to Carney complex and most likely do not represent an incomplete form of Carney complex. 相似文献
44.
Lindsley WG Collicott SH Franz GN Stolarik B McKinney W Frazer DG 《Annals of biomedical engineering》2005,33(3):365-375
Airway closure and gas trapping can occur during lung deflation and inflation when fluid menisci form across the lumina of respiratory passageways. Previous analyses of the behavior of liquid in airways have assumed that the airway is completely wetted or that the contact angle of the liquid-gas interface with the airway wall is 0, and thus that the airway fluid forms an axisymmetric surface. However, some investigators have suggested that liquid in the airways is discontinuous and that contact angles can be as high as 67. In this study we consider the characteristics of constant curvature surfaces that could form a stable liquid-gas interface in a cylindrical airway. Our analysis suggests that, for small liquid volumes, asymmetric droplets are more likely to form than axisymmetric toroids. In addition, if the fluid contact angle is greater than 13, asymmetric droplets can sustain larger liquid volumes than axisymmetric toroids before collapsing to form menisci. These results suggest that (1) fluid formations other than axisymmetric toroids could occur in the airways; and (2) the analysis of the behavior of fluids and the development of liquid menisci within the lungs should include the potential role of asymmetric droplets. 相似文献
45.
Zusammenfassung Es werden zwei Kammern zur mikroskopischen Beobachtung und mikrophotometrischen Untersuchung von lebenden Zellen beschrieben. Mit ihrer Hilfe ist es möglich. Zellen ohne Schädigung mechanisch so zu stabilisiren, dasß sie bis zu Stunden an derselben Stelle liegen bleiben.In der Einstromkammer liegen die Zellen in einlagiger Schicht zwischen einem Deckglas und einer licht- und gasdurchlässigen Folie, die durch Adhäsion festgehalten wird. Der an die Folie angrenzende Raum kann mit gewünschten Gasgemischen durchströmt werden.In der Zweistromkammer liegen die Zellen zwischen zwei lichtdurchlässigen Folien, von denen die eine Gase, die andere auch Flüssigkeiten und gelöste Substanzen durchtreten läßt. Der an die flüssigkeitsdurchlässige Folie angrenzende Raum kann mit gewünschten Lösungen, der andere gleichzeitig mit Gasgemischen beströmt werden. Die Funktionsweise der Zweistromkammer wird am Beispiel der Formänderung von Erythrocyten bei Beströmen mit Lösungen verschiedenen osmotischen Druckes demonstriert. Beide Kammern eignen sich zur Vital-Mikroskopie und Photometrie von einzelnen Zellen, insbesondere Blutzellen und Gewebeschnitten. 相似文献
46.
Franz Thimm Marilene Carvalho Martha Babka Elisabeth Meier zu Verl 《Pflügers Archiv : European journal of physiology》1984,400(3):286-293
The hypothesis that metabolic receptors in skeletal muscle influence heart-rate during exercise was tested by means of a perfused preparation of the rat's hind legs. The isolated leg was connected to the body only by nerve and bone and was perfused with tyrode solution. The humoral changes of exercise were simulated by perfusing with modified tyrode solutions in which concentration of K+, osmolality, concentrations of lactic acid, and inorganic phosphate were changed to reflect to those occurring during heavy exercise. Only perfusion with a solution enriched with lactic acid elicited a significant increase in heart-rate. The response disappeared when the nerve supply to the leg was cooled or sectioned. 20–60 s after the start of perfusion with solution of high [lactic acid] heart-rate began to increase reaching a maximum (
± SE = 20.2 ± 8.2,n = 7) after about 2 min. The effect on heart-rate increased when the venous concentration of lactic acid was increased the range from 3 to 10 mmol/l. In further experiments, we tried to separate the effects of pH and lactate. Heart-rate responses were induced only at low pH and at low pH the extent to which heart-rate changed increased with increases in lactate concentration. 相似文献
47.
IFN-gamma-enhanced allergen penetration across respiratory epithelium augments allergic inflammation 总被引:2,自引:0,他引:2
Reisinger J Triendl A Küchler E Bohle B Krauth MT Rauter I Valent P Koenig F Valenta R Niederberger V 《The Journal of allergy and clinical immunology》2005,115(5):973-981
BACKGROUND: Respiratory allergen contact is the critical event in the elicitation and boosting of allergen-specific immune responses, as well as in the induction of immediate and late inflammatory reactions. OBJECTIVE: We sought to investigate the influence of various factors of allergic inflammation on the integrity and barrier function of respiratory epithelium for allergens. METHODS: We cultured the human bronchial epithelial cell line 16HBE14o- in a transwell culture system as a surrogate of intact respiratory epithelium and used purified iodine 125-labeled recombinant major birch pollen allergen (rBet v 1) to study the extent, kinetics, and factors influencing transepithelial allergen penetration. RESULTS: Culture supernatants from activated allergen-specific T H 1 clones decreased transepithelial resistance. A screening of various factors (histamine, IFN-gamma, IL-1beta, IL-2, IL-3, IL-4, IL-5, IL-8, IL-12, and TNF-alpha) identified IFN-gamma as a potent factor capable of reducing epithelial barrier properties and enhancing transepithelial allergen penetration. Increased submucosal allergen concentrations caused by IFN-gamma-mediated reduction of epithelial barrier function provoked a more than 7-fold augmentation of histamine release from sensitized basophils. CONCLUSION: These results demonstrate that the T H 1 cell-derived cytokine IFN-gamma facilitates allergen penetration through the respiratory epithelium and thereby can aggravate allergic inflammation. 相似文献
48.
Adolf Dörge Franz X. Beck Roger Rick Wolfram Nagel Klaus Thurau 《Pflügers Archiv : European journal of physiology》1990,416(3):335-338
The role of mitochondria-rich cells (MR cells) in transepithelial Na transport was investigated by determining electrolyte concentrations and Rb uptake in individual cells of frog skin epithelium using electron microprobe analysis. Measurements were performed under control conditions and after blocking the transepithelial Na transport with amiloride. Under control conditions, Na and Cl concentrations of MR cells scattered much more than those of principal cells and ranged from a few up to more than 30 mmol/kg wet weight. Rb uptake from the basal side into individual MR cells also showed a large variation and was, on the average, much less pronounced than into the principal cells. In principal cells, amiloride reduced the Na concentration and Rb accumulation. In contrast, no effect was observed upon electrolyte concentration and Rb uptake of MR cells. Rb uptake was correlated to the Na concentration of MR cells both under control conditions and after amiloride. It is concluded that, in contrast to the principal cells, MR cells are not involved in amiloride-sensitive transepithelial Na transport and that their Na/K-pump activity is very low. 相似文献
49.
Stephan A. Wacker Franz Oswald Jörg Wiedenmann Walter Knöchel 《Developmental dynamics》2007,236(2):473-480
Lineage labeling is one of the most important techniques in developmental biology. Most recently, a set of photoactivatable fluorescent proteins originating from marine cnidarians became available. Here, we introduce the application of the green to red photoconvertible protein EosFP as a novel technique to analyze early vertebrate development. Both injection of EosFP mRNA and purified, recombinant EosFP followed by a light-driven green to red conversion allow lineage labeling in virtually any temporal and spatial dimension during embryonic development for at least 2 weeks. Specific staining of cells from nonsurface layers is greatly facilitated by light-driven conversion of EosFP compared with traditional methods. Therefore, green to red photoactivatable proteins promise to be a powerful tool with the potential to satisfy the increasing demand for methods enabling detailed phenotypical analyses after manipulations of morphogenetic events, gene expression, or signal transduction. 相似文献
50.