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71.
We report and discuss a case of Kimura's disease with an unusual eosinophilic epithelioid granulomatous reaction. A 3-year-old Japanese boy with eosinophilia and a high concentration of IgE developed lymphadenopathy and multiple cervical masses. A lymph node biopsy demonstrated the infiltration of eosinophils in the stroma, which is consistent with the findings of Kimura's disease. Interestingly, a number of apoptotic eosinophils was detected in the infiltrating eosinophils. Multiple epithelioid granulomas with central eosinophilic abscesses and necrosis were also observed. Macrophages and giant cells had phagocytosed the apoptotic eosinophils at the edge of the granulomas. In situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay showed that the TUNEL-positive eosinophils were both in the macrophages and in the central eosinophilic abscesses of the granulomas. These findings suggest that the eosinophils had undergone an accelerated apoptosis in this case of Kimura's disease, and that the epithelioid granulomas were produced by phagocytosis of the apoptotic eosinophils by macrophages.  相似文献   
72.
An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500–600 ml watery sputum a day, loss of weight, and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregulary-shaped cytoplasmic vacuoles suggestive of mucin.  相似文献   
73.
The adsorption of trimethylammonium glycol chitosan iodide (TGCI) on Dowex CCR-2 resin was investigated at different pH values and resin weights. The concentration of Na+ or Ca2+ ions, released by the ion exchange reaction with TGCI, was measured by inductively coupled plasma spectroscopy. It was found that the amount of the released ions is comparable to that of the absorbed TGCI. This indicates that the salt-linkage formation of carboxylate ions of the exchanger with ⊕N(CH3)3-groups in TGCI follows a stoichiometric relationship. This result is discussed in connection with the form of the polymer layer adsorbed on the solid surface.  相似文献   
74.
The dimerization of 1-alkynes by rhodium(I) complexes in the presence of phosphorus ligands is described. The products are linear and branched dimers, the ratio of which is correlated with the electronic parameters, vCO of Ni(CO)3L, of the ligands L, but no simple correlation is apparent between their steric parameter and the selectivity. Electron-donating ligands promote the formation of the linear dimer. The substituents of the 1-alkynes also affect the distribution of linear and branched dimers. Electron-donating substituents prefer linear isomer to branched one. The reactivity of the substituted 1-alkynes (R? C?C? H) increased with substituent R in the order   相似文献   
75.
In hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC), serum alanine aminotransferase (ALT) is frequently sustained on a high level after hepatectomy, with the formation of recurrent HCC tumors during follow-up periods. We investigated whether or not postoperative serum ALT level affects the interval before recurrence in hepatitis C virus-associated HCC. The subjects studied were 50 hepatectomized HCC patients who were HCV-Ab(+), and underwent a curable surgery in our Hospital from June 1990 to December 1999. We assessed the significance of the postoperative serum ALT level affecting tumor-free survival rates, as compared with other clinicopathological parameters, using univariate and multivariate Cox proportional hazard analysis. Thereafter, tumor-free and overall survival rates after hepatectomy were compared between high and low ALT groups, using Kaplan-Meier plotting and a log-rank test. The factor of ALT levels (a high or low ALT group) was most strongly associated with a tumor-free survival rate. Both tumor-free and overall survival rates were significantly poorer in the high ALT group than in the low ALT group among HCV-associated HCC cases (p<0.05). The results in this study suggest that postoperative hepatitis, which is indicated by sustained high ALT levels, may shorten the interval before recurrence in HCV-associated HCC. We should take care to control postoperative hepatitis to improve the prognoses of HCV-associated HCC cases.  相似文献   
76.
BACKGROUND: Either omega-5 gliadin or high molecular weight glutenin is known to be a major allergen in wheat-dependent exercise-induced anaphylaxis (WDEIA). It is generally considered that gluten specific IgE score is more reliable than that of wheat specific IgE score for the diagnosis of WDEIA. Our aim was to verify the significance of gluten specific IgE in the diagnosis of WDEIA. METHODS: We evaluated the result of gluten CAP-RAST score and omega-5 gliadin specific IgE score on four WDEIA patients who visited our hospital during the years 2004 and 2005, whose diagnosis were onfirmed by prick tests, immunoblot tests and provocation tests. RESULTS: Contrary to our expectations, all four patients showed negative gluten CAP-RAST scores, however all patient's omega-5 gliadin specific IgE scores were positive. CONCLUSION: Our results suggest that gluten specific CAP-RAST score is unreliable in the diagnosis of WDEIA. On the other hand omega-5 gliadin specific IgE score is possibly a better candidate as a diagnostic tool for WDEIA.  相似文献   
77.
We have previously reported that continuous infusion of dobutamine into the coronary artery induces positive inotropic effects but induces no detrimental effects in cross-circulated, excised normal rat hearts and even in Ca2+ overload-induced contractile failing rat hearts. However, we hypothesized that some detrimental effects on left ventricular (LV) function are induced after continuous dobutamine infusion and the following clearance of blood dobutamine, as is the case after beta-adrenergic receptor stimulation. To test this hypothesis, we investigated LV mechanical work and energetics in the same type of preparations that underwent continuous dobutamine infusion and clearance of blood dobutamine. We found that both mean end-systolic pressure and systolic pressure-volume area (PVA; a measure of total mechanical energy per beat) at midrange LV volume were significantly (P < 0.01) decreased. The mean myocardial oxygen consumption per beat intercept, which is composed of for the total Ca2+ handling in excitation-contraction coupling and basal metabolism, of the and PVA linear relation was also significantly (P < 0.05) decreased (n=8). The mean slope of the linear relation was unchanged in such hearts. Post-dobutamine basal metabolism was unchanged (n = 5 of the 8 hearts). The moderate proteolysis of a cytoskeleton protein, alpha-fodrin was identified (n = 7 of the 8 hearts with the decreased intercept), after clearance of blood dobutamine. In agreement with our hypothesis, the detrimental effect of the post-beta-adrenergic receptor stimulation was induced by a moderate concentration of dobutamine; we found systolic dysfunction due to the impairment of Ca2+ handling in excitation-contraction coupling in the rat LV and proteolysis of a cytoskeleton protein, alpha-fodrin.  相似文献   
78.
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations.  相似文献   
79.
Marfan syndrome (MFS) is an autosomal dominant disorder of the extracellular matrix. Allelic variations in the gene for fibrillin-1 (FBN1) have been shown to cause MFS. To date, over 550 mutations have been identified in patients with MFS and related connective tissue diseases. However, about a half of MFS cases do not possess mutations in the FBN1 gene. These findings raise the possibility that variants located in other genes cause or modify MFS. To explore this possibility, firstly we analyzed FBN1 allelic variants in 12 Japanese patients with MFS, and secondly we analyzed fibrillin-3 gene (FBN3) in patients without FBN1 mutations using conformation sensitive gel electrophoresis (CSGE) and direct sequencing analysis. We identified three novel FBN1 mutations and ten FBN3 single nucleotide polymorphisms (SNPs). In this report, we could not detect a responsible mutation of the FBN3 gene for MFS. Although the number of the cases in this report is small, at least these results suggest that disease-causing mutations in exon regions of the FBN3 gene are very rare in MFS.Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers: AB177797, AB177798, AB177799, AB177800, AB177801, AB177802, AB177803  相似文献   
80.
Diffusion coefficient of water through dental composite resin   总被引:1,自引:0,他引:1  
Asaoka K  Hirano S 《Biomaterials》2003,24(6):975-979
Water sorption of polymer filling materials affects dimensional stability, mechanical properties and bonding strength with tooth structures. To clarify the effect of the degradation on service life and micro-leakage, the diffusion coefficient of water through the resin should be identified. Distributions of time-dependent water concentrations in the resin were computed. Water sorption of composite resin discs with different thicknesses was measured and compared with the solution of Fick's second law. The diffusion coefficient of water through the resin discs was computed to be D=3.9-5.0 x 10(-13)m(2)/s from the measurements of specimens with different thicknesses. Results of water sorption measurements for the discs with different thicknesses were in good agreement with the theoretical results. The relationship among the thickness of the disc, the diffusion coefficient and the water sorption ratio was shown clearly. The testing method for water sorption by International Standard ISO 4049 for resin-based filling materials was discussed.  相似文献   
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