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991.
992.
993.
A 68-year-old man developed pandysautonomia with severe orthostatic dysfunction, fixed heart rate, low serum levels of norepinephrine and epinephrine, absent sympathetic skin responses, and pupillary abnormalities. CSF protein was 92 mg/dl. In spite of a good recovery following corticosteroid administration, a relapse occurred, with accompanying sensory symptoms confined to both arms. Fatal sudden cardiac arrest occurred after 4 months. Autopsy revealed numerous lymphocytic infiltrates, predominantly in autonomic and sensory ganglia and, to a lesser extent, in the nerve roots, spinal cord, and brainstem without evidence for an underlying tumor. This case provides histopathologic evidence for an inflammatory etiology of panautonomic neuropathy in some patients. 相似文献
994.
P. G?r?g 《International journal of experimental pathology》1991,72(2):227-237
The ability of native and oxidized lipids and lipoproteins to stimulate production of reactive oxygen species (ROS; superoxide and hydrogen peroxide) by human blood monocytes has been studied in vitro. Neither native human low density lipoprotein (LDL), ''altered'' LDL (oxidized either by lipoxygenase, activated human monocytes or air) nor oxidized cholesterol had any significant effect on ROS production of monocytes. However, different oxidation products of a lipid emulsion (Lipofundin; largely consisting of linoleic acid oxidized either by lipoxygenase, Fe3+ or ultraviolet irradiation) greatly enhanced ROS production of monocytes. A hypothesis that activation of circulating leucocytes by oxidized fatty acids may generate oxidized plasma LDL, was tested in rabbits. Characteristics of LDL, separated from rabbit plasma 6 h after intravenous injection of an oxidized lipid emulsion, was compared to that of LDL isolated before the lipid treatment. Post-treatment LDL-fraction of plasma had increased lipid peroxide content and compared to the pretreatment LDL, caused a threefold increase in the incorporation of cholesterol into cultured (rat aortic) endothelial cells. The observed intense and lasting stimulation of monocytes by oxidized polyunsaturated fatty acids in vitro, and the generation of ''altered'' LDL by these oxidized lipids in vivo suggests a mechanism by which atherogenic oxidized LDL could form in the circulation. 相似文献
995.
G Balogh 《Orvosi hetilap》1991,132(38):2075-2080
Experiences obtained with 400 cases of thoracal empyema are described. The fact that the rate of lethality was 18.7% until present points out to the severity of the disease. The semi-conservative therapeutical methods used by the author (drainage, drainage and pleura lavage, pleura lavage and thoracoscopy, balance drainage) are presented. With their sensibly more frequent use the rate of operation could be reduced by 8% (from 36.5% to 28.5%) and the lethality rate by 7.6% (from 18.7% to 11.1). Further improvement of the results may be expected of the increased number of early detection (basic care), concentration of empyemic patients in special institutes (departments, wards) and due to it of a more efficient special treatment of uniform contemplation. 相似文献
996.
G Hochhaus H Derendorf H M?llmann J Barth 《Journal of pharmaceutical and biomedical analysis》1991,9(9):761-767
A combined LC/RIA procedure is described for the selective determination of dexamethasone (DEX) and its prodrug dexamethasone-21-isonicotinate (DIN) in plasma. The low affinity of the employed dexamethasone antiserum for DIN (cross-reactivity less than 0.5%) allowed the direct determination of DEX in plasma extracts. For the determination of DIN, both substances of interest were separated by LC, the DIN containing fraction was collected, hydrolysed and the generated DEX was consequently assayed by radioimmunoassay. The assay detection limits were 0.1 ng ml-1 for DEX and 0.75 ng ml-1 for DIN. For both substances, inter- and intra-day variabilities (RSDs) were 6 and 12%, respectively. 相似文献
997.
The antiparasitic drug, suramin, has antiproliferative effects in human carcinoma cells. It has been suggested that this occurs through blockade of growth factor-receptor interactions. Three types of evidence that suramin rapidly inhibits cellular respiration or disrupts cellular energy balance in intact cells of the human prostate carcinoma cell line, DU145, are presented. Beginning at approximately 10(-4) M, suramin rapidly causes dose-dependent inhibition of tetrazolium conversion by mitochondrial dehydrogenases in intact cells, demonstrating an inhibition of respiration. This effect is reversed by exchange with suramin-free media but not by pretreatment with serum, epidermal growth factor, insulin-like growth factor I, acidic and basic fibroblast growth factors, or calcium. Rhodamine 123 (10 micrograms/ml) uptake by mitochondria in intact DU145 cells is inhibited in the presence of 10(-3) M suramin. Treatment with 10(-4)-10(-3) M suramin causes the loss of rhodamine 123 from cells with mitochondria prestained with rhodamine 123, indicating that suramin is acting as an ionophore or respiratory poison. Also shown by electron microscopy are progressive toxic changes in mitochondria of DU145 cells within 1 h after treatment with 10(-4) M suramin. These data indicate that in intact DU145 cells 10(-4) M suramin rapidly disrupts cellular energy balance or respiration as seen by three studies of mitochondrial state. Disruption of energy balance or respiration represents a likely antiproliferative mechanism, as is thought to be a primary mechanism for the action of suramin in parasitic diseases. This proposed mechanism of action for suramin can explain the most prominent observed clinical toxicities of nephrotoxicity, adrenal toxicity, coagulopathy, and demyelinating neuropathy. 相似文献
998.
999.
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