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991.
Hypersomnia is known to be associated with symptoms, such as excessive daytime sleepiness, headache, and decreases in vigilance. We report for the first time a patient who initially presented with symptoms for idiopathic hypersomnia but after a thorough diagnostic evaluation was diagnosed as suffering from Lyme disease. This finding stresses the need to potentially include diagnostic tools, like lumbar puncture, in diagnostic procedures, in order to rule out inflammatory diseases of the central nervous system mimicking hypersomnia symptoms.  相似文献   
992.
Aberrant activation of Notch receptors has been implicated in breast cancer; however, the mechanisms contributing to Notch-dependent transformation remain elusive because Notch displays dichotomous functional activities, promoting both proliferation and growth arrest. We investigated the cellular basis for the heterogeneous responses to Notch pathway activation in 3D cultures of MCF-10A mammary epithelial cells. Expression of a constitutively active Notch-1 intracellular domain (NICD) was found to induce two distinct types of 3D structures: large, hyperproliferative structures and small, growth-arrested structures with reduced cell-to-matrix adhesion. Interestingly, we found that these heterogeneous phenotypes reflect differences in Notch pathway activation levels; high Notch activity caused down-regulation of multiple matrix-adhesion genes and inhibition of proliferation, whereas low Notch activity maintained matrix adhesion and provoked a strong hyperproliferative response. Moreover, microarray analyses implicated NICD-induced p63 down-regulation in loss of matrix adhesion. In addition, a reverse-phase protein array-based analysis and subsequent loss-of-function studies identified STAT3 as a dominant downstream mediator of the NICD-induced outgrowth. These results indicate that the phenotypic responses to Notch are determined by the dose of pathway activation; and this dose affects the balance between growth-stimulative and growth-suppressive effects. This unique feature of Notch signaling provides insights into mechanisms that contribute to the dichotomous effects of Notch during development and tumorigenesis.  相似文献   
993.
Previous studies showed that repeated ingestion of erythrosine B (artificial food color) developed behavioral hyperactivity, but nothing is known about its single administration effect as well as the neurochemical (s) involvement. The present study provides evidence that a single higher dosage (10, 100 or 200 mg/kg, p.o.) of erythrosine administration to young adult male rats reduced motor activity (MA) maximally at 2 h and brain regional (medulla-pons, hippocampus and hypothalamus) serotonergic activity (measuring steady-state levels of 5-HT and 5-HIAA, pargyline-induced 5-HT accumulation and 5-HIAA declination rate and 5-HT receptor binding) under similar experimental condition. The degree of erythrosine-induced inhibition of both MA and brain regional serotonergic activity was dosage dependent. Lower dosage (1 mg/kg, p.o.) did not affect either of the above. Erythrosine (100 or 200 mg/kg, p.o.)-induced MA suppression was also observed in the presence of specific MAO-A inhibitor, clorgyline (5 mg/kg, i.p.) or MAO-B inhibitor, deprenyl (5 mg/kg, i.p.); but their co-application (5 mg/kg, i.p., each) effectively prevented the erythrosine-induced motor suppression. Altogether these results suggest that a single higher dosage of erythrosine (10-200 mg/kg, p.o.) may reduce MA by reducing serotonergic activity with modulation of central dopaminergic activity depending on the brain regions.  相似文献   
994.
Oral manifestations of tuberculosis are quite rare with an incidence rate of 1.4%. The tongue is the most common site of oral tuberculosis having varied presentations. Lingual tuberculosis is a diagnostic dilemma because of its rarity, particularly in immunocompetent patients. We are reporting a rare case of primary tuberculosis of the tongue in a 38 year old male diagnosed on fine needle aspiration cytology.  相似文献   
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There are occasional pediatric reports of parvovirus B19-associated transient acute hepatitis and hepatic failure. A case of a 34-year-old immunocompetent woman who developed severe and prolonged but self-limited acute hepatitis and myelosuppression following acute parvovirus B19 infection is reported. Parvovirus B19 may be the causative agent in some adult cases of acute non-A-E viral hepatitis and acute liver failure.  相似文献   
999.
1000.
Electron spin resonance (ESR) spin trapping methodology has been used to study the reactions of manganese dusts with glutathione, employing alpha-(4-pyridyl-1-oxide)-N-tert-butyl-nitrone (PBN) and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as spin traps. The results show evidence for the glutathionyl radical formation in the reactions of both MnO2 and manganese (III) acetate with glutathione. Based on these experimental observations, we hypothesise that the mechanism of neurotoxic effects of manganese might be due to the fact that the generation of glutathionyl radicals depletes the glutathione pool and reduces the glutathione shield against free radical products of dopamine metabolism and manganese induced reactive oxygenated species.  相似文献   
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