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51.
Vitamin H (biotin) was incorporated into a hydrophobically modified polysaccharide, pullulan acetate (PA), in order to improve the cancer-targeting activity and internalization of self-assembled nanoparticles. The biotinylated pullulan acetate (BPA) nanoparticles were prepared by a diafiltration method and the mean diameter was approximately 100 nm. Three samples of biotinylated pullulan acetate (BPA), comprising 7 (BPA 1), 20 (BPA 2), and 39 (BPA 3) vitamin H groups per 100 anhydroglucose units of PA, were synthesized. The critical aggregation concentrations (CAC) of the BPA nanoparticles in distilled water were 3.1 x 10(-3), 4.3 x 10(-3) and 6.8 x 10(-3) mg/ml for BPA 1, BPA 2, and BPA 3, respectively. Adriamycin (ADR) was loaded into the BPA nanoparticles as a model drug. The loading efficiencies and ADR content in the BPA nanoparticles decreased with increasing vitamin H content due to a lower hydrophobicity. The RITC-labeled BPA nanoparticles exhibited very strong adsorption to the HepG2 cells, while the RITC-labeled PA nanoparticles did not show any significant interaction. The degree of the interaction increased with increasing vitamin H content. Confocal laser microscopy also revealed that internalization of the BPA nanoparticles into the cancer cells depended on the vitamin H content.  相似文献   
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PURPOSE:To ascertain the attitude of cancer patients and their families toward disclosure of terminal illness to the patient. PATIENTS AND METHODS: We constructed a questionnaire that included demographic and clinical information and delivered it to 758 consecutive individuals (433 cancer patients and 325 families that have a relative with cancer) at seven university hospitals and one national cancer center in Korea. RESULTS: 380 cancer patients and one member from each of 281 families that have a relative with cancer completed the questionnaire. Cancer patients were more likely than family members to believe that patients should be informed of the terminal illness (96.1% v 76.9%; P <.001). Fifty percent of the family members and 78.3% of the patients thought that the doctor in charge should be the one who informs the patient. Additionally, 71.7% of the patients and 43.6% of the family members thought that patients should be informed immediately after the diagnosis. Stepwise multiple logistic regression indicated that the patient group was more likely than the family group to want the patient to be informed of the terminal illness (odds ratio [OR], 9.76; 95% CI, 4.31 to 22.14), by the doctor (OR, 4.00; 95% CI, 2.61 to 6.11), and immediately after the diagnosis (OR, 3.64; 95% CI, 2.45 to 5.41). CONCLUSION: Our findings indicated that most cancer patients want to be informed if their illness is terminal, and physicians should realize that the patient and the family unit may differ in their attitude toward such a disclosure. Our results also reflect the importance of how information is given to the patient.  相似文献   
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放疗联合肝动脉化疗栓塞治疗肝癌的研究进展   总被引:3,自引:1,他引:3  
对于不能手术的原发性肝癌患者,放射治疗配合肝动脉栓塞化疗(TACE)的疗效明显好于单纯放疗或单纯化疗,治疗并发症的发生率和程度可以接受,大多数患者可以耐受。放疗配合动脉栓塞化疗是治疗不能手术的原发性肝癌患者的非常有发展前途的治疗方法。现综述这二种治疗方法的技术特点、疗效和协同作用研究的现状及最新进展。  相似文献   
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目的 探讨三七、茜草(SQ)复方治疗置铜宫内节育器(Cu-IUD)所致子宫异常出血的作用机理。方法 制 作家兔置Cu-IUD动物模型,以吲哚美辛作对照,观察SQ复方对置Cu-IUD家兔模型子宫匀浆中组织型纤溶酶原激 活物(t-PA)活性的影响。结果 置Cu-IUD家兔模型子宫匀浆中t-PA的含量增高(P<0.01),经SQ复方治疗后与模 型组比较有显著性差异(P<0.01),说明SQ复方能减少家兔子宫匀浆中t-PA的含量,降低t-PA的活性。结论 SQ 复方通过降低置Cu-IUD家兔子宫内膜局部的纤溶活性而达到止血的目的。  相似文献   
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Angiogenesis is an essential process in the development, growth, and metastasis of malignant tumors including lung cancer. DNA sequence variations in the vascular endothelial growth factor (VEGF) gene may lead to altered VEGF production and/or activity, thereby causing interindividual differences in the susceptibility to lung cancer via their actions on the pathways of tumor angiogenesis. To test this hypothesis, we investigated the potential association between three VEGF polymorphisms (-460T > C, +405C > G, and 936C > T)/haplotypes and the risk of lung cancer in a Korean population. VEGF genotypes were determined in 432 lung cancer patients and 432 healthy controls that were frequency matched for age and sex. VEGF haplotypes were predicted using Bayesian algorithm in the phase program. Compared with the combined +405 CC and CG genotype, the +405 GG genotype found associated with a significantly decreased risk of small cell carcinoma [SCC; adjusted odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.17-0.78]. The 936 CT genotype and the combined 936 CT and TT genotype were also associated with a significantly decreased risk of SCC compared with the 936 CC genotype (adjusted OR, 0.47; 95% CI, 0.26-0.85 and adjusted OR, 0.44; 95% CI, 0.24-0.80, respectively). Haplotype CGT was associated with a significantly decreased risk of SCC (adjusted OR, 0.39; 95% CI, 0.18-0.87), whereas haplotype TCC conferred a significantly increased risk of SCC (adjusted OR, 1.63; 95% CI, 1.14-2.33). None of the VEGF polymorphisms studied significantly influenced the susceptibility to lung cancer except SCC. However, haplotypes TCT and TGT were significantly associated with the risk of overall lung cancer, respectively (adjusted OR, 0.38; 95% CI, 0.25-0.60 and adjusted OR, 3.94; 95% CI, 2.00-7.76, respectively). These effects of haplotypes TCT and TGT on lung cancer risk were observed in three major histologic types of lung cancer. These results suggest that the VEGF gene may be contribute to an inherited predisposition to lung cancer.  相似文献   
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背景与目的:颅叫管瘤为难治性肿瘤,其预后不良,复发机制尚不清楚。本研究检测颅Ⅱ阏管瘤组织中微血管密度(microvascular density,MVD)及血管内皮生长因子vascular endothelial growth factor,VEGF表达.分析其与肿瘤预后等生物学行为的关系。方法:采取前瞻性队列研究方案,经纳入、排除标准筛选卅颅咽管釉质上皮型肿瘤32例、鳞形乳头瘤型肿瘤31例,平均随访843个月,收集原发及复发患者的肿瘤组织标本,应用单克隆抗体CD34、VEGF抗体检测肿瘤组织MVD及VEGF蛋白表达,计算机辅助成像系统对其作出定量分析,分析其与肿瘤复发等生物学行为的关系。结果:VEGF蛋白、MVD计数在颅咽管瘤队列复发组、非复发组间不具有显著性差异(P〉0.05),而在颅咽管瘤不同病理类型间差异则具有显著性(P〈0.05)。结论:VEGF蛋白、MVD计数与肿瘤复发无关,不能预测颅咽管瘤复发的危险性,但可为了解肿瘤的同有侵袭性行为提供参考。  相似文献   
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