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61.
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   
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63.
A case of infantile XX male syndrome with bilateral scrotal testes and penoscrotal hypospadias is presented. No evidence of XX/XY mosaicism or Y chromatin was obtained in preparations from cultures of the peripheral blood, skin fibroblast, or other tissues. Although true hermaphroditism was suspected, exploration of the bilateral gonadal structures failed to detect the presence of ovarian structures, either grossly or microscopically. Furthermore, exploratory laparotomy revealed no Mullerian structures. The difficulty of early diagnosis of XX males in infancy is emphasized.  相似文献   
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65.
The benign epithelial neoplasm liver cell adenoma is rare, especially in childhood. We report 2 such cases, 1 of which was associated with Prader-Willi syndrome. Differential diagnosis of the liver cell adenomas on the basis of histopathologic findings proved difficult and was based on the absence of cellular and nuclear atypia, mitotic activity, and invasive growth. In both cases, immunohistochemical staining demonstrated the nuclear accumulation of beta-catenin, and in 1 case, the tumor cells carried a mutation of the beta-catenin gene. Recently, disregulation of the Wnt/beta-catenin pathway, attributable to abnormalities of the beta-catenin gene, has been reported to be a major event in the development of hepatocellular carcinomas and hepatoblastomas. Our report may be the first to describe the beta-catenin abnormalities in childhood liver cell adenoma. These findings imply that abnormalities of beta-catenin can be an early initiating event in human liver tumorigenesis.  相似文献   
66.
Skinfold thicknessess (SFT) were measured at ulnar, triceps, subscapular and suprailiac sites in 730 boys and 724 girls (age 3–12 years) whose stature ranged from 100 to 150 cm and whose weight was within ±20% of the average. Means and standard deviation (SD) were calculated after logarithmic transformation of the original skinfold readings to demonstrate stature-based standards of SFT in Japanese children. The means of SFT exhibited nadirs (boys/ girls: ulnar 5.1/5.9 mm, triceps 7.9/9.5 mm, subscapular 4.9/6.1 mm, suprailiac 4.5/6.2 mm) in subjects 110–115 cm tall except for ulnar SFT in girls. SFT values increased as children increased in stature. Standard deviations of SFT at the four sites in short children (staturte < mean ?1 SD) were estimated using the stature-based standard as well as an age-based standard. Susms of the SDs assessed by the age-based standard were significantly smaller than those assessed by the stature-based standard in boys (P < 0.05) and girls (P < 0.01) with short stature, suggesting that SFT in short children was falsely understimated by the age-based standard. Thus, the stature-based standard is beneficial for the assessment of SFT, especially in children whose stature is below the mean ?-1 SD. © 1995 Wiley-Liss, Inc.  相似文献   
67.
Previously, we established the in vivo lung metastasis model of rat HCC induced by two hepatocarcinogens, diethylnitrosamine (DEN) and N-nitrosomorpholine (NMOR) at a dose of 120 ppm. This model allows us to investigate modifying factors leading to the inhibition of metastasis formation. However, low survival rates made the evaluation of metastasis formation difficult. The current experiments were conducted to modify the experimental protocol to improve survival and to establish a better animal metastasis model. Lower doses of NMOR (80 or 40 ppm in drinking water) were given to F344 rats for 14 weeks after DEN treatment. Survival rates in the 80 ppm group and in the 40 ppm group were 57% and 81%, respectively and these values were significantly higher than that in 120 ppm. Incidences of lung metastasis in the 40 ppm group steadily increased up to 67% by week 36 while that in the 80 ppm increased sharply up to 86% by week 24. Severity of lung metastases in the 40 ppm group at week 36 was mild compared with the 80 ppm group at week 24. In the second experiment, in order to characterize HCC development and lung metastasis in the 40 ppm group, rats given DEN and then followed with 40 ppm NMOR were killed sequentially. Development of HCC was observed at week 14 and reached 100% incidence at week 20. First lung metastatic lesions were evident at week 22, and incidence of lung metastasis reached 100%. Tumor cells were identified in the blood at week 20 by RT-PCR. The current study revealed that 40 ppm NMOR for 14 weeks after DEN treatment developed HCC without lung metastases at week 22, then HCC with a frequent lung metastasis at week 40. Thus, it can be said that this system is a more appropriate model for elucidation of mechanisms of metastasis and also for analysis of factors to inhibit natural metastasis.  相似文献   
68.
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   
69.
The Rad17-replication factor C (Rad17-RFC) and Rad9-Rad1-Hus1 complexes are thought to function in the early phase of cell-cycle checkpoint control as sensors for genome damage and genome replication errors. However, genetic analysis of the functions of these complexes in vertebrates is complicated by the lethality of these gene disruptions in embryonic mouse cells. We disrupted the Rad17 and Rad9 loci by gene targeting in the chicken B lymphocyte line DT40. Rad17-/- and Rad9-/- DT40 cells are viable, and are highly sensitive to UV irradiation, alkylating agents, and DNA replication inhibitors, such as hydroxyurea. We further found that Rad17-/- and Rad9-/- but not ATM-/- cells are defective in S-phase DNA damage checkpoint controls and in the cellular response to stalled DNA replication. These results indicate a critical role for chicken Rad17 and Rad9 in the cellular response to stalled DNA replication and DNA damage.  相似文献   
70.
OBJECTIVE: Inhaled corticosteroids play a pivotal role in the treatment of asthma. To observe the mechanisms of glucocorticoids, we focused our study on the comparison of several glucocorticoids' effects on eotaxin expression in the airway epithelial cells. METHODS: Airway epithelial cell line BEAS-2B was cultured in vitro. Cells were preincubated with or without glucocorticoids (becromethasone dipropionate; BDP, budesonide; BUD, fluticasone propionate; FP) and stimulated with TNFalpha and/or IL-4. Protein levels of eotaxin in the supernatants of the cultured cells were determined by ELISA. RESULTS AND CONCLUSIONS: TNFalpha and IL-4 increased the levels of eotaxin in BEAS-2B cells. Combination of these cytokines synergistically upregulated the eotaxin expression as reported previously. Each glucocorticoid significantly inhibited the expression of eotaxin protein induced with TNFalpha and IL-4 and the compared efficacy was in order of FP>BUD>BDP. FP seemed most potent and the inhibitory effect was also observed with relatively low concentration such as 10 (-10)M. Taken together, the comparison of the potency of each glucocorticoid using airway epithelial cells may reflect the efficacy of these drugs in asthmatics.  相似文献   
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