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不同表面处理的种植入早期表面沉积物的分析研究 总被引:1,自引:1,他引:1
目的:比较两种不同表面处理的种植体在植入早期表面沉积物的差异及其骨组织反应。方法:将表面经双重酸-双氧水热处理和双重酸处理的种植体分别植入兔子胫骨内,然后,采用带能谱分析的扫描电镜观测2、4、8周带种植体的骨组织。结果:植入2周后在两组种植体表面均沉积富含钙磷层;4周时这层结构大部分消失,但双重酸-双氧水-热处理组可见较多的骨生成细胞附着在种植体表面并形成新骨。8周时两组种植体表面均附着一些新骨,但以双重酸-双氧水-热处理组相对较多。结论:两组种植体在植入早期表面均可形成富含钙磷层。 相似文献
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Annette Paschen Mingxia Song Wolfram Osen Xuan Duc Nguyen Jan Mueller-Berghaus Daniela Fink Nadine Daniel Mariel Donzeau Wolfgang Nagel Harald Kropshofer Dirk Schadendorf 《Clinical cancer research》2005,11(14):5241-5247
PURPOSE: The frequently expressed differentiation antigen tyrosinase-related protein-2 (TRP-2) has repeatedly been described as a target of spontaneous cytotoxic T-cell responses in melanoma patients, suggesting that it might be an ideal candidate antigen for T cell-based immunotherapy. As a prerequisite for immunization, T-cell epitopes have to be identified. Whereas a number of HLA class I-presented TRP-2-derived epitopes are known, information about HLA class II-presented antigenic ligands recognized by CD4+ T helper (Th) cells is limited. EXPERIMENTAL DESIGN: The search for TRP-2-derived Th epitopes was carried out by competitive in vitro peptide binding studies with predicted HLA-DRB1*0301 ligands in combination with peptide and protein immunizations of HLA-DRB1*0301 transgenic mice. In vivo selected candidate epitopes were subsequently verified for their immunogenicity in human T-cell cultures. RESULTS: This strategy led to the characterization of TRP-2(60-74) as an HLA-DRB1*0301-restricted Th epitope. Importantly, TRP-2(60-74)-reactive human CD4+ Th cell lines, specifically recognizing target cells loaded with recombinant TRP-2 protein, could be established by repeated peptide stimulation of peripheral blood lymphocytes from several HLA-DRB1*03+ melanoma patients. Even short-term peptide stimulation of patients' peripheral blood lymphocytes showed the presence of TRP-2(60-74)-reactive T cells, suggesting that these T cells were already activated in vivo. CONCLUSION: Peptide TRP-2(60-74) might be a useful tool for the improvement of immunotherapy and immune monitoring of melanoma patients. 相似文献
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Donna L Forrest Donna E Hogge Thomas J Nevill Stephen H Nantel Michael J Barnett John D Shepherd Heather J Sutherland Cynthia L Toze Clayton A Smith Julye C Lavoie Kevin W Song Nicholas J Voss Randy D Gascoyne Joseph M Connors 《Journal of clinical oncology》2005,23(31):7994-8002
PURPOSE: To determine the incidence of second malignancies among patients with Hodgkin's lymphoma (HL) treated with autologous hematopoietic stem cell transplantation (AHSCT) compared with patients receiving conventional therapy alone and to identify potential risk factors for their occurrence. PATIENTS AND METHODS: We analyzed data on 1,732 consecutive patients with HL treated at the British Columbia Cancer Agency from 1976 to 2001, including 202 patients undergoing AHSCT. The median follow-up duration was 9.8 years for the whole cohort, 9.7 years for those patients treated with conventional therapy, and 7.8 years from AHSCT. RESULTS: The cumulative incidence of developing any second malignancy 15 years after therapy for HL was 9% (risk ratio = 3.5; P < .001); however, the incidence did not differ between those patients receiving conventional therapy alone compared with those undergoing AHSCT (10% and 8%, respectively; P = .48). In multivariate analysis, the only factor significantly associated with an increased risk of developing any second neoplasm or solid tumor was age > or = 35 years (P < .0001). An increased risk of therapy-induced acute myeloid leukemia and therapy-induced myelodysplastic syndrome was seen for patients aged > or = 35 years (P = .03) and stage III/IV (P = .04). CONCLUSION: Patients with HL are at increased risk of developing a second neoplasm. However, those patients undergoing AHSCT do not seem to be at greater risk compared with those patients receiving conventional therapy alone, at least during the first decade after therapy. 相似文献
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氨氯地平消旋体经D-(—)-酒石酸拆分,得到(S)-(—)-氨氯地平,再与苯磺酸成盐制得钙通道阻滞剂(S)-(—)-氨氯地平苯磺酸盐二水合物,收率67%,光学纯度近100%. 相似文献
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目的 探讨C反应蛋白与白蛋白比值(CRP/ALB)对川崎病(KD)早期丙种球蛋白(IVIG)抵抗的预测价值。方法 将2020年1月至2023年6月成都医学院第一附属医院住院的118例病程≤5 d的KD患儿分为IVIG抵抗组和IVIG敏感组,分析患儿临床资料,采用多因素Logistic回归分析探究独立危险因素,ROC曲线探究CRP/ALB对KD患儿早期IVIG抵抗的预测价值。结果 IVIG抵抗组比IVIG敏感组有更高水平的白细胞计数(WBC)、CRP、CRP/ALB和更低水平的血红蛋白(HGB)。CRP/ALB升高和HGB降低是KD患儿早期IVIG抵抗的独立危险因素。CRP/ALB可预测KD患儿早期IVIG抵抗(AUC=0.664)。结论 CRP/ALB升高和HGB降低是KD患儿早期IVIG抵抗的独立危险因素,CRP/ALB可有效预测KD患儿早期IVIG抵抗。 相似文献