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51.
We report a case of medulloblastoma as a secondary malignancy in a patient treated for immature teratoma of the ovary (ITO). ITO is a rare but curable tumor of the ovary using combination chemotherapy. There is a great deal of interest in the long-term effects of chemotherapy in these patients. Once regarded as fatal not many series of patients with ITO have been reported with the long follow up as in the present case. This case may start a debate on the susceptibility of central nervous system tumors following chemotherapy in patients with ITO.  相似文献   
52.
Is the Cell Death in Mesial Temporal Sclerosis Apoptotic?   总被引:6,自引:0,他引:6  
PURPOSE: Mesial temporal sclerosis (MTS) is characterized by neuronal loss in the hippocampus. Studies on experimental models and patients with intractable epilepsy suggest that apoptosis may be involved in neuronal death induced by recurrent seizures. METHODS: We searched evidence for apoptotic cell death in temporal lobes resected from drug-resistant epilepsy patients with MTS by using the terminal deoxynucleotidyl transferase (TdT) and digoxigenin-11-dUTP (TUNEL) method and immunohistochemistry for Bcl-2, Bax, and caspase-cleaved actin fragment, fractin. The temporal lobe specimens were obtained from 15 patients (six women and nine men; mean age, 29 +/- 8 years). RESULTS: Unlike that in normal adult brain, we observed Bcl-2 immunoreactivity in some of the remaining neurons dispersed throughout the hippocampus proper as well as in most of the reactive astroglia. Bax immunopositivity was increased in almost all neurons. Fractin immunostaining, an indicator of caspase activity, was detected in approximately 10% of these neurons. Despite increased Bax expression and activation of caspases, we could not find evidence for DNA fragmentation by TUNEL staining. We also could not detect typical apoptotic changes in nuclear morphology by Hoechst-33258 or hematoxylin counterstaining. CONCLUSIONS: These data suggest that either apoptosis is not involved in cell loss in MTS, or a very slow rate of cell demise may have precluded detecting TUNEL-positive neurons dying through apoptosis. Increased Bax expression and activation of caspases support the latter possibility.  相似文献   
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The soluble venom from the scorpion Androctonus crassicauda was fractionated by high performance liquid chromatography. At least 44 different sub-fractions were resolved and collected for finger print mass analysis using an electrospray mass spectrometer. This analysis revealed the presence of 80 distinct molecular mass components, from which five were further characterized. A peptide, named Acra1 was fully sequenced. It contains 58 amino acid residues cross-bridged by six cysteines forming three disulfide pairs, with a molecular mass of 6497 Da. A second purified peptide named Acra2 was partially sequenced with a molecular mass of 7849 Da. Acra1 is toxic and Acra2 is lethal to mice, at the dose assayed. Additionally, a cDNA library of the venomous gland of one specimen was prepared and several clones were obtained among which is one that codes for Acra1. Three analog gene sequences were found with point mutations either in the section that corresponds to the mature peptide or to the signal peptide. The signal peptide is 22 amino acid residues long. Several other gene sequences obtained suggest the presence in this venom of three distinct groups of peptides, among which are peptides similar to known Na(+)-channel specific toxins of other scorpions. A new type of peptide was identified with odd number of cysteines (seven), allowing the formation of heterodimers with molecular masses in the range of 16,000 atomic mass units (a.m.u.).  相似文献   
55.
Fc receptors (FcR) play an important role in immune regulation. This might be linked to the variability in immune response, therefore relating to the pathogenesis of atopic diseases. The aim of the present study was to evaluate the Fc γ RIIIa gene polymorphism in Turkish children with asthma and allergic rhinitis. The study included 364 atopic children (184 bronchial asthma, 180 allergic rhinitis) and 234 healthy subjects as the control group, aged between 5 to 16 years. Patients were recruited from outpatient clinics of allergy and general pediatric care. Plasma IgE concentrations were measured by immunoassays and skin prick test was done in children with atopic diseases. The Fc γ RIIIa gene polymorphism was determined using the polymerase chain reaction method. Distribution of V158V genotype was significantly different among patient groups compared to controls (for asthmatic children OR: 5.33, 95% CI: 2.80–10.23, p < 0.001; for allergic rhinitis OR: 3.25, 95% CI: 1.75–6.07, p = 0.001). Distribution of 158 V allele was significantly different among asthmatic children (OR: 2.20, 95% CI: 1.65–2.92, p < 0.001) and allergic rhinitis patients (OR: 1.77, 95% CI: 1.32–2.35, p < 0.001) compared to healthy controls. Our study shows that the V158V genotype in Fc γ RIIIa gene polymorphism may be a genetic risk factor for the development of atopic diseases.  相似文献   
56.
To investigate the effect of cyclosporine A (Cyc A) on the development of fibroadenomas, 30 renal transplant patients and 20 chronic renal failure patients on dialysis were breast examined with ultrasonography and/or mammography. Of the renal transplant patients, 17 were receiving Cyc A-based combination therapy for immunosuppression. All patients were female with the age range of 29.7+/-9.2 years in the transplant group and 33.95+/-9.91 in the dialysis group. Eight of the 17 patients receiving Cyc A had fibroadenomas, 5 of them having bilateral lesions. None of the other patients, those on dialysis and on non-Cyc A combination therapy had fibroadenomas. A significant difference for fibroadenoma incidence in patients receiving Cyc A combination immunosuppression was found.  相似文献   
57.
BACKGROUND: Oleic acid (OA) is oxidized more rapidly than is palmitic acid (PA). OBJECTIVE: We hypothesized that changing the dietary intakes of PA and OA would affect fatty acid oxidation and energy expenditure. DESIGN: A double-masked trial was conducted in 43 healthy young adults, who, after a 28-d, baseline, solid-food diet (41% of energy as fat, 8.4% as PA, and 13.1% as OA), were randomly assigned to one of two 28-d formula diets: high PA (40% of energy as fat, 16.8% as PA, and 16.4% as OA; n = 21) or high OA (40% of energy as fat, 1.7% as PA, and 31.4% as OA; n = 22). Differences in the change from baseline were evaluated by analysis of covariance. RESULTS: In the fed state, the respiratory quotient was lower (P = 0.01) with the high OA (0.86 +/- 0.01) than with the high-PA (0.89 +/- 0.01) diet, and the rate of fat oxidation was higher (P = 0.03) with the high-OA (0.0008 +/- 0.0001) than with the high-PA (0.0005 +/- 0.0001 mg . kg fat-free mass(-1) . min(-1)) diet. Resting energy expenditure in the fed and fasting states was not significantly different between groups. Change in daily energy expenditure in the high-OA group (9 +/- 60 kcal/d) was significantly different from that in the high-PA group (-214 +/- 69 kcal/d; P = 0.02 or 0.04 when expressed per fat-free mass). CONCLUSIONS: Increases in dietary PA decrease fat oxidation and daily energy expenditure, whereas decreases in PA and increases in OA had the opposite effect. Increases in dietary PA may increase the risk of obesity and insulin resistance.  相似文献   
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59.
The clinical, echocardiographic and angiographic aspects of a four-month-old boy with double-outlet left ventricle, atrioventricular discordance, L-malposition of the great arteries, ventricular septal defect and pulmonary stenosis are described. Additionally, in this patient, the right arcus aorta and the ligament of ductus arteriosus caused anterior compression of the trachea. The anterior position of the morphological left ventricle is the most interesting feature.  相似文献   
60.
Neonatal lupus erythematosus (NLE) is a disease primarily characterized by cardiac and/or cutaneous involvement. Hepatic, hematological, neurological and pulmonary involvement are rare manifestations and normally considered as mild and transient complications. But recent studies have shown more frequent hepatic involvement in NLE. We report a two month-old male infant, born to a clinically asymptomatic mother, presenting with significant hepatic involvement and annular, erythematous plaques with hyperkeratotic borders at the eyebrow region and anterior surface of trunk. Both the infant and his mother were positive for anti-Ro (SS-A) and anti-La (SS-B).  相似文献   
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