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31.
The B7/CD28 co-stimulatory pathway plays a critical role in T cell activation and differentiation. Our previous study demonstrated that administration of B7.2-Ig fusion proteins to tumor-bearing mice elicits IL-4-dependent, CD8+ T cell-mediated tumor regression. Here, we investigated whether B7.2-Ig stimulation of tumor-sensitized CD8+ CTL precursors during in vitro antigen re-sensitization actually results in their differentiation into mature CTLs and if so, whether such a process depends on IL-4 signals. Splenocytes from tumor-sensitized (tumor-bearing or tumor-immunized) mice exhibited low levels of anti-tumor CTL responses upon culturing alone, but induced strikingly enhanced CTL responses when stimulated in vitro with B7.2-Ig fusion proteins. Because CTLs were not generated from normal splenocytes even by B7.2-Ig stimulation, the expression of the B7.2-Ig effect required the in vivo tumor sensitization of CD8+ CTL precursors. Administration of anti-CD4 or anti-CD40 ligand (CD40L) to mice before tumor sensitization resulted in almost complete inhibition of CTL responses generated in the subsequent culture containing B7.2-Ig. In contrast, anti-IL-4 did not influence in vivo tumor sensitization required for CTL induction. However, B7.2-Ig stimulation of tumor-sensitized splenocytes enhanced IL-4 production and neutralization of this IL-4 with anti-IL-4 potently down-regulated CTL responses. These results indicate that B7.2-Ig enhances IL-4-dependent differentiation of anti-tumor CD8+ CTL precursors that can be sensitized in vivo depending on collaboration with CD4+ T cells involving CD40L function.  相似文献   
32.
红外多波长无创人体血糖检测阵列模型的研究   总被引:2,自引:0,他引:2  
无创血糖监测不仅可以减少患者的痛苦,还能进行连续测量,从而降低并发症的发生,它是一种不需收集血样进行体内血糖浓度测量的新技术。本文根据朗伯-比尔定律(The Lambert—Beer Law)原理,为克服无创血糖检测研究中的难点和缺陷,详细分析了血糖红外光谱的吸收特性,利用阵列技术设计了红外多波长无创血糖检测传感器阵列模型,对关键技术进行了讨论。用ME算法建立了信号检测和标定数学模型,结合了人体各种影响因素,使红外无创血糖检测的精度和稳定性得到了改善。列举了详细的实验实施步骤,同时叙述了系统调试的详细过程,讨论了无创血糖检测中需要注意的问题。  相似文献   
33.
Ng SB  Sittampalam K  Goh YH  Eu KW 《Pathology》2003,35(1):42-46
The increased incidence of thyroid carcinomas in familial adenomatous polyposis (FAP) patients is well recognised. These thyroid neoplasms display distinctive clinicopathological features and generally show good prognostic outcome. Recently, unusual sporadic tumours that share the morphological features of FAP-associated thyroid carcinomas have also been described. In this report, we document a case of a thyroid tumour in a previously well, 46-year-old female. Histology revealed a circumscribed neoplasm composed of tubular, papillary, cribriform and solid areas. The pseudostratified columnar tumour cells showed occasional nuclear grooves and rare nuclear inclusions. Immunohistochemistry showed positive staining with antibodies to cytokeratin AE1/AE3, oestrogen and progesterone receptor proteins. Focal immunoreactivity was also noted with antibodies to thyroglobulin, epithelial membrane antigen, 34betaE12 and cytokeratin CK7. The absence of polyps on colonoscopy and germline mutation in the adenomatous polyposis coli (APC) gene provides evidence that this tumour represents the sporadic counterpart of FAP-associated thyroid carcinoma. The patient is well with no evidence of disease 7 months following resection of the tumour. The differential diagnoses and molecular genetics of this unusual tumour are discussed.  相似文献   
34.
多囊卵巢综合征高雄激素血症患者瘦素水平的检测及评价   总被引:1,自引:0,他引:1  
目的探讨多囊卵巢综合征高雄激素血症进行患者瘦素(Leptin)水平及其与睾酮(T)、体重指数(BMI)的关系.方法采用放射免疫分析法(RIA)检测53例PCOS患者血清瘦素水平,其中非肥胖组PCOS患者36例,正常对照30例;肥胖组PCOS患者17例,正常对照20例.结果肥胖组及非肥胖组PCOS高雄激素血症患者血清瘦素水平均明显高于相当体重指数的正常对照组,有显著差异(p均<0.01);两组瘦素水平分别与其睾酮水平进行相关性分析,均显著正相关(r=0.51,p<0.01和r=0.58,p<0.01);非肥胖组PCOS患者血清瘦素水平与其BMI相关分析显示,无相关性;肥胖组PCOS患者血清瘦素水平与其BMI进行相关分析,显著正相关(p=0.56,p<0.01).结论高瘦素血症是PCOS患者的内分泌特征之一,PCOS高雄激素血症的形成与高瘦素水平有关;超重或肥胖的PCOS高雄激素血症患者存在瘦素抵抗现象.  相似文献   
35.
Patients with Crohn's disease have an increased risk of developing intestinal tumours. However, the carcinogenic mechanisms remain poorly understood. To address this question, this report describes an unusual case of Crohn's disease complicated by synchronous small intestinal and colonic adenocarcinomas. Genetic events in both the tumours and their adjacent mucosae were evaluated and the tumorigenesis of these cancers is discussed.  相似文献   
36.
OBJECTIVE: To explore the relationship of the genetic polymorphisms and the haplotypes in hMLH1 and hMSH3 gene with the risk of papillary thyroid carcinoma (PTC) in Chinese Hans. METHODS: A hospital based 1:1 matched case-control study was carried out. The polymorphisms for 204 pairs of PTC cases and healthy controls were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele specific oligonucleotide (PCR-ASO) assays. RESULTS: (1) The PTC risk was marginally increased in the hMLH1 1151TA genotype, with odds ratio (OR) of 2.15 (95%CI: 0.99-4.85); the PTC risk was significantly increased in the mutant genotype 1151TA+AA, with OR of 2.15 (95%CI: 1.02-4.69); (2) The haplotypes of -93G, 1151A, 655A in the hMLH1 gene could increase the PTC risk, with OR of 2.67 (95%CI: 1.16-6.53, P=0.011), compared with the haplotype of -93G, 1151T, 655A; (3) Compared to 3124A, 2835G haplotype in hMSH3 gene, the 3124G, 2835A haplotype could increase the PTC risk marginally, with OR of 3.08 (95%CI: 0.92-13.25). CONCLUSION: The 1151T/A polymorphism in hMLH1 was associated with PTC; both the haplotype of -93G, 1151A, 655A in hMLH1 and the 3124G, 2835A haplotype in hMSH3 were associated with PTC.  相似文献   
37.
目的探讨重点理工科学校大一新生焦虑状况及相关因素,为进行针对性的干预提供依据。方法以广东某重点理工高校2007级的大一学生为研究对象,采用自行设计一般项目调查表、状态-特质焦虑量表(STAI)、匹兹堡睡眠质量指数量表(PSQI)、应付方式问卷进行测评。结果测查学生不论男女状态焦虑、特质焦虑分均显著高于地方常模;19.29%的学生睡眠质量较差;高状态焦虑组和高特质焦虑组解决问题、求助应付因子分均显著低于低状态焦虑组和低特质焦虑组,而自责、幻想、退避应付因子分则显著高于低状态焦虑组和低特质焦虑组;多元逐步回归分析说明,学生如常采用解决问题应付方式,在一定程度上可避免焦虑的产生,而睡眠质量差、采用自责应对方式则可加重焦虑水平。结论采取有效的认知应对策略其意义是使学生改变应激源,以使其变得威胁较小或变成挑战,把情绪基调训练成兴奋、期待和征服。  相似文献   
38.
本文通过金葡菌、大肠杆菌内毒素、地塞米松加内毒素等三种不同的攻毒方法复制了“热毒血瘀证”的动物模型。结果提示三种模型在血凝学指标上均表现为KPTT、PT明显缩短,而在血液流变学指标上则有不同。金葡菌所造模型表现为明显的高粘状态,内毒素模型则表现为明显的低粘状态,地塞米松加内毒素模型则改变不明显。  相似文献   
39.
40.
胃癌 (Gastric Cancer,GC) 是全球第五大最常见的恶性肿瘤,也是第四大癌症死亡相关原因。胃癌异质性明显,肿瘤微环境复杂,免疫检查点抑制剂虽然在晚期胃癌中展现出一定抗肿瘤疗效,但获益人群仍在少数。吲哚胺2,3-双加氧酶 1 (Indoleamine 2,3-Dioxygenase 1,IDO1) 是色氨酸沿犬尿氨酸途径代谢中的关键酶,对肿瘤免疫逃逸起到了关键作用。目前已有多项研究表明IDO1在胃癌发生发展及幽门螺杆菌感染和EB病毒感染中发挥重要作用,所以靶向IDO1有望成为胃癌免疫治疗的新策略。本文就IDO1作用机制、IDO1在胃癌及相关疾病中的研究进展及IDO1抑制剂在胃癌中的应用前景进行综述。  相似文献   
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