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51.
Summary Intraperitoneal (i.p.) injection of Dextran Sulfate (D.S.) 500 during a limited period of time influences the course of herpes simplex-virus-infections. D.S.500 was found to reduce the resistance of mice for some herpes simplex-virus strains (Len, L3-2s, Haase) if given between 16 hours before and 2 hours after i.p. infection. The decrease of resistance could be correlated with an increase of the virus content of liver, spleen, brain and spinal cord. Injection of herpes simplex-virus-specific immune serum counteracted the effect of D.S.500 on the course of infections. Conversely, D.S.500 increased the resistance of mice to another group of herpes simplex-viruses (strains D-316, Thea, DD), if given 3 to 8 hours before infection.These effects are ascribed to a special interaction of D.S.500 with macrophages and probably other virus-susceptible cells of the peritoneal cavity and elsewhere with a resulting counteraction to the virus infection.With 2 FiguresIn part presented at the 76th Ordinary meeting of the Society for General Microbiology at the University of Cambridge, April 5–8, 1976.In partial fulfilment of the requirements for the MD degree. 相似文献
52.
Gastrointestinal zygomycosis caused by Mucor indicus in a patient with acute traumatic brain injury.
Maria Deja Steffen Wolf Steffen Weber-Carstens Thomas-Nicolas Lehmann Andreas Adler Markus Ruhnke Kathrin Tintelnot 《Medical mycology》2006,44(7):683-687
We report a gastrointestinal infection caused by Mucor indicus in a patient with severe head injuries. Monotherapy with high-dose liposomal amphotericin B successfully eradicated the mucormycosis. Nevertheless, subsequently a hemicolectomy was necessary due to recurrent bleeding from a deep ulcer. Mucor indicus is an uncommon fungal pathogen, typically found in starters used for food fermentation. Reviewing other reports on Mucor indicus infections, primary gastrointestinal manifestations seem to be typical and indicate an oral route of infection. 相似文献
53.
The plating efficiency for fungal yeast cells is usually less than that expected from microscopic counts, and a number of explanations for this phenomenon have been proposed. The present study was undertaken to explore possible reasons for reduced plating efficiency of Candida albicans. Explanations that we evaluated and found unlikely included: ineffectiveness of different culture media and/or incubation temperatures for growing colonies, insufficient area of the plate available for expression of individual colonies, production of microcolonies, and inaccurate counting of the organisms in the inoculum. An assay for delivery of the inoculum into tissue culture plate wells indicated that reduced delivery of the organisms accounted for lower than expected plating efficiency. C. albicans yeast cells grown under low glucose conditions and expected to have reduced adhesiveness were found to have higher values for both delivery and plating efficiency in our assays. In summary, our results indicate that reduced plating efficiency for C. albicans under the conditions used for these experiments is best explained by the loss of some yeast cells during preparation of the inocula or delivery of the yeast cells onto the plates. 相似文献
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Anne Mellon Mogensen Esther Hage Steffen Bülow 《Virchows Archiv : an international journal of pathology》1989,414(4):321-324
Summary Electron microscopical studies on endocrine cell hyperplasia of duodenal adenomas from five patients with familial adenomatous polyposis were performed. All the endocrine cell types normally found in the duodenal mucosa were identified. A constant feature was proliferation of duodenal-enterochromaffin cells but an increase in the number of all other endocrine cell types apart from pyloricgastrin cells and somatostatin cells, was also observed. Certain types of intestinal endocrine cells (the intestinal enterochromaffin cell and the glicentin cell) are rare cells in the normal duodenal mucosa. The finding of these cells may indicate increased biological aggressivity. 相似文献
56.
Steffen Dietzel Anna Jauch Dirk Kienle Guoquiong Qu Heidi Holtgreve-Grez Roland Eils Christian Munkel Michael Bittner Paul S. Meltzer Jeffrey M. Trent Thomas Cremer 《Chromosome research》1998,6(1):25-33
Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding. 相似文献
57.
Differences in cytokine secretion by intestinal mononuclear cells, peripheral blood monocytes and alveolar macrophages from HIV-infected patients. 总被引:2,自引:1,他引:2 下载免费PDF全文
M Steffen H C Reinecker J Petersen C Doehn I Pflüger A Voss A Raedler 《Clinical and experimental immunology》1993,91(1):30-36
Mononuclear cells of the lamina propria (LpMNC), isolated from endoscopically taken biopsies of the large bowel from AIDS patients, were analysed for their ability to secrete tumour necrosis factor-alpha (TNF-alpha), IL-1 beta and IL-6. Stimulation of LpMNC from normal controls with pokeweed mitogen (PWM) led to a time- and dose-dependent enhancement of TNF-alpha, IL-1 beta and IL-6 secretion. In contrast, PWM stimulation of LpMNC from AIDS patients resulted in only a small increase in TNF-alpha release. Constitutive secretion of IL-1 beta and IL-6 in these patients was already increased to the concentration range of stimulated cells from normal controls and could not be further increased, probably due to maximal in vivo stimulation. Secretion of TNF-alpha, IL-1 beta and IL-6 by peripheral blood monocytes (PBM) and alveolar macrophages from AIDS patients was elevated with or without stimulation compared with normal controls. Obviously, the regulation of TNF-alpha secretion is dependent on the microenvironment. Since it is known that interferon-gamma (IFN-gamma) may induce the production of TNF-alpha, the secretion of this cytokine was examined. Release of IFN-gamma was constitutively and under stimulation lowered in LpMNC from AIDS patients compared with normal controls. Addition of IFN-gamma to LpMNC did not result in enhanced TNF-alpha secretion. Our data indicate a defective function of intestinal mononuclear cells in AIDS patients as shown by the diminished TNF-alpha secretion. 相似文献
58.
R. Müller H. M. Steffen R. Brunner M. Pollok C. A. Baldamus W. Kaufmann 《Journal of molecular medicine (Berlin, Germany)》1991,69(16):742-748
Summary Nine patients on maintenance hemodialysis and transfusion-demanding renal anemia (group A) were treated with rHuEPO 120 IU/kg i.v. three times per week. Hemoglobin-content was raised from 7.2±0.9 to 10.4±0.8 g/dl. In all patients blood pressure rose, three patients developed arterial hypertension. Mean diastoloic blood pressure was 66±12 and 78±16 mmHg (p<0.001) before and after rHuEPO. Rise in blood pressure was accompanied by a significant fall in plasma-noradrenaline-levels (from 498±100 to 383±75 pg/ml;p<0.05) and alpha2-adrenoceptor-density (from 574±76 to 384±49;p<0.05). Compared to nine patients on maintenance hemodialysis and hematocrit over 30% (group B), patients with severe renal anemia (group A before treatment) had higher densities of alpha2-adrenoceptors (574±76 vs. 218±32;p<0.001) despite higher plasma-noradrenaline-levels (498±100 vs. 399±63; n.s.). We suppose a anemia-related disturbance of alpha2-receptor-function with the result of abolished receptor down-regulation and impaired vascular reagibility to vasoconstricting stimuli. With the correction of anemia receptor-function improves, receptor down-regulation as well as vascular reagibility is re-established resulting in augmented vascular resistance and higher blood pressure.
Abkürzungen rHuEPO rekombinantes humanes Erythropoietin - teMAP mittlerer arterieller Blutdruck - RR Blutdrucknach RIVA-ROCCI - RBF regionaler Blutfluß - RPR regionaler peripherer Widerstand 相似文献
Abkürzungen rHuEPO rekombinantes humanes Erythropoietin - teMAP mittlerer arterieller Blutdruck - RR Blutdrucknach RIVA-ROCCI - RBF regionaler Blutfluß - RPR regionaler peripherer Widerstand 相似文献
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