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151.
This life history research examined seniors' life experiences and perceived connections to illnesses. From a randomly selected sample of 190 seniors'interviews, 107 deemed to be the most expressive life stories were selected as the focus for this analysis. All seniors lived independently in a Canadian prairie city, were 60 years of age or older, Caucasian, European decent, had a chronic illness, and told of lives touched by the Great Depression and World War II. Given the paucity of research exploring seniors' life histories, these findings increase understanding of how life experiences shape seniors' identities. Four main themes emerged to describe seniors' lives: chaos, tragedy, quest, and romance. Findings reported here show that seniors with optimistic perceptions do not connect their life experiences with illnesses. Seniors with pessimistic perceptions frequently connect their life experiences with present illnesses and are most likely to remember past abuse and coping with abuse.  相似文献   
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We show the case of an adult male with a previous diagnosis of an 'aspirin-like' defect in platelet secretion responses scheduled for cardiac valve surgery. Perioperative management and bleeding prevention were made following experts' recommendations.  相似文献   
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A pseudophakic patient with gyrate atrophy of the choroid and retina presented with bilateral intraocular lens (IOL) dislocation with the capsular bag several years after uneventful cataract surgery. The patient had not performed strenuous physical activity. One IOL was initially repositioned by nonsurgical manipulations, while the other required surgical repositioning. Eventually, IOL exchange was performed successfully in both eyes.  相似文献   
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Brusatol, a quassinoid isolated from the fruit of Brucea javanica, induces cell differentiation with various leukemic cell lines in the concentration range of 5-25 ng/ml. To investigate its mechanism of action, cultured HL-60 cells were treated with brusatol (25 ng/ml) for various periods of time and qualitatively analyzed for differential gene expression using a cDNA macroarray. As suggested by these preliminary data, we investigated the effect of brusatol on the Rel/nuclear factor-kappa B (NF-kappaB) family members and their role in HL-60 cell differentiation. When cells were treated with brusatol (25 ng/ml), p100/p52, p105/p50 and p65 mRNA were found to be up-regulated with a maximum after 8 h. As determined by electrophoretic mobility shift assays (EMSA), NF-kappaB was activated, involving p50 and p65. Moreover, immunoblots showed a decrease of IkappaBalpha and generation of the phosphorylated form of IkappaBalpha in whole cell lysates. Cell differentiation induced by brusatol was inhibited by SN50, a NF-kappaB translocation inhibitor. These results strongly suggest that brusatol induces activation of NF-kappaB and the activation and translocation of NF-kappaB into the nucleus is responsible for promoting HL-60 cell differentiation.  相似文献   
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PURPOSE: Our study investigated the influence of recombinant human erythropoietin (rHuEPO) treatment, inducing raised hemoglobin levels in nonanemic mice, on intratumor oxygenation before and during fractionated irradiation. Furthermore, the consequences of rHuEPO administration on tumor response to fractionated radiotherapy (RT) were evaluated. METHODS AND MATERIALS: Experiments were performed on two human malignant glioma (GBM Nan1 and U87) xenografted in nude mice. RHuEPO was daily delivered (0.3 IU/g/day, 5 days/week). Tumor hypoxia was assessed before (T1) and during (T6) fractionated irradiation using (1) pO(2)-Histograph (Eppendorf, Hamburg, Germany) and (2) the EF5-binding assay. Vascular density was determined using type IV collagen immunostaining. To assess RT efficacy, the irradiation schedule was 20 fractions of 2 Gy, once daily, 5 days/week over 4 weeks. RESULTS: At T1, hemoglobin levels in rHuEPO-treated mice were significantly increased. Percentage of pO(2) values <2.5 mm Hg was reduced in rHuEPO-treated tumors as compared with control groups (37.1 +/- 19.1% vs. 58.5 +/- 27.0%; p = 0.009 for GBM Nan1; 81.6 +/- 13.4% vs. 91.5 +/- 8.3%; p = 0.035 for U87). The decrease of viable hypoxic tumor cells fraction after rHuEPO was confirmed by the EF5-binding assay. Vascular density was not altered after rHuEPO treatment. At T6, rHuEPO reduced the hypoxic fraction by about 20% (p = 0.036 and p = 0.171) in GBM Nan1 and U87 irradiated tumors. RHuEPO did not influence tumor growth by itself. RT alone or combined with rHuEPO induced a significant tumor growth delay. Finally, rHuEPO significantly enhanced RT efficacy (p = 0.012 in GBM Nan1 and p = 0.037 in U87), resulting in radiopotentiation ratios of 1.21 and 1.54 for respective models. CONCLUSIONS: Our results indicate that rHuEPO, by enhancing blood oxygen-carrying capacity, decreases intrinsic tumor hypoxia and maintains its effect during fractionated irradiation in malignant glioma xenografts. Therefore, rHuEPO contributes to radiosensitize these tumors.  相似文献   
160.
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