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61.
Apoptotic cell death in the lactating mammary gland is enhanced by a folding variant of α-lactalbumin 总被引:1,自引:0,他引:1
Apoptosis is essential to eliminate secretory epithelial cells during the involution of the mammary gland. The environmental regulation of this process is however, poorly understood. This study tested the effect of HAMLET (human -lactalbumin made lethal to tumor cells) on mammary cells. Plastic pellets containing HAMLET were implanted into the fourth inguinal mammary gland of lactating mice for 3 days. Exposure of mammary tissue to HAMLET resulted in morphological changes typical for apoptosis and in a stimulation of caspase-3 activity in alveolar epithelial cells near the HAMLET pellets but not more distant to the pellet or in contralateral glands. The effect was specific for HAMLET and no effects were observed when mammary glands were exposed to native a-lactalbumin or fatty acid alone. HAMLET also induced cell death in vitro in a mouse mammary epithelial cell line. The results suggest that HAMLET can mediate apoptotic cell death in mammary gland tissue.Received 30 January 2004; received after revision 5 March 2004; accepted 16 March 2004 相似文献
62.
63.
Our understanding of how immune responses are generated and regulated drives the design of possible immunotherapies for cancer
patients. For that reason, we first describe briefly the actual immunological theories and their common perspectives about
cancer vaccine development. Second, we describe cancer vaccines that are able to induce tumor-specific immune responses in
cancer patients. However, these responses are not always followed by tumor rejection. At the end of the review, we discuss
two possible reasons that might explain this dichotomy of cancer immunology. First, the immune response generated, although
detectable, may not be quantitatively sufficient to reject the tumor. Second, the tumor microenvironment may modulate tumor
cell susceptibility to the systemic immune response induced by the immunization. Finally, we discuss what, in our opinion,
might be the best way to improve cancer vaccine strategies and how the relationship between the tumor and its surroundings
might be studied in more details.
Received 21 June 2001; received after revision 15 August 2001; accepted 15 August 2001 相似文献
64.
FANGJianwu HUANGSiluo LIUHuisheng M.Crepin XUTao LIUJianfeng 《科学通报(英文版)》2003,48(15):1539-1547
Fibroblast growth factor-2 (FGF-2) is a member of a large family of proteins that bind heparin and heparan sulfate and modulate the function of a wide range of cell types. It has been proved that FGF-2 stimulates the growth and development of new blood vessels (angiogenesis) that contribute to the pathogenesis of several diseases (i.e. cancer, atherosclerosis). However, many of the biological activities of FGF-2 have been found to depend on its receptor抯 intrinsic tyrosine kinase activity and second messengers such as the mitogen activated protein kinases. This review will focus on the mechanism of FGF-2/FGFR induced signaling pathway in tumor and human breast cancer. 相似文献
65.
从术后肝癌病人的外周血中诱导树突状细胞(DC),并经自体肝癌细胞裂解物致敏DC,用流式细胞仪、^3H-TdR掺入法及MTT法检测了DC表面分子的表达、DC刺激T细胞的增殖效应及DC诱导的T细胞对肝癌细胞的杀伤作用,进而比较经自体肝癌细胞裂解物致敏的DC与其它条件下的DC功能的差异.结果显示:肝癌细胞裂解物致敏DC的功能较未致敏DC显著提高,其可诱导自体混合淋巴细胞强的增殖效应,同时诱导的T细胞对自体肝癌细胞有较强的杀伤率. 相似文献
66.
目的:明确原发性肝癌介入治疗护理经验及注意事项.方法:回顾性分析2004年~2005年我院所收治的42例原发性肝癌患者的临床资料.结果:经皮经导管肝动脉栓塞术前后,由于精神因素、体质差异、化疗药物等的作用,患者都有不同程度紧张、恶心、呕吐、腹痛、发热等症状.结论:通过正确的术前、术中及术后的护理,可以使肝癌介入治疗顺利进行,减少副作用,提高疗效. 相似文献
67.
YU DanMi XIAO SuYao TONG ChunYi CHEN Lin LIU XuanMing 《科学通报(英文版)》2007,52(21):2913-2918
Dialdehyde starch nanoparticles (DASNP) were prepared by the redox reaction of NaIO4 and starch in water-in-oil microemulsion. IR spectrum showed that DASNP had aldehyde groups, and quantitative alkali consumption showed that its dialdehyde content was about (50±5)%. The average diameter of DASNP determined by SEM was about 100 nm. TGA-DTA showed that its thermal stability was better than starch nanoparticle (StNP) and dialdehyde starch (DAS). Its low biological toxicity was detected by cell experiment. Also the best mass ratio of doxorubicin (DOX) to combined DASNP detected by UV-VIS was 15 : 1, and the product was effective for controlled release of DOX. The cell experiment showed that the drug-carrier particle (DOX-DASNP) can release DOX for a long time and strengthened the effect of the anticancer drug. This work demonstrates that the DASNP, which has good thermal stability, small particle size, low biological toxicity, and slowly anticancer drug-releasing to strengthen drug effect, is a potentially useful carrier for anticancer drug. 相似文献
68.
采用荧光实时定量PCR的方法在48个非小细胞肺癌组织以及配对的正常肺组织中检测Eph/ephrin 基因的mRNA水平.发现肺癌组织中EphB4, EphB3 和 ephrin-A5的表达水平与配对的正常肺组织相比分别上调了60%,81%和65%,并具有显著的统计学差异. 而且,统计学分析发现ephrin-A5的表达水平与肿瘤分型、转移、性别、吸烟以及诊断年龄等临床病理学参数之间存在显著的相关性.此外,EphA2的表达水平与肿瘤大小、家族遗传史以及诊断年龄之间也存在显著的相关性.总之,这些结果提示EphB4, EphA2, EphB3 和ephrin-A5 在肺癌的发生和发展过程中可能以一种单独或者协同的形式发挥作用.这些蛋白有可能成为研究和诊断肺癌的重要靶向基因. 相似文献
69.
VEGF 和 PCNA在乳腺癌组织中表达的意义 总被引:1,自引:0,他引:1
为了探讨血管内皮生长因子(VEGF)和增殖细胞核抗原(PCNA)在乳腺癌组织中的表达及其与病理学分级关系,采用免疫组织化学SP法检测102例乳腺癌及其中48例癌旁正常乳腺组织中VEGF和PCNA的表达,实验结果显示VEGF在乳腺癌组织中的阳性表达率为84.31%,癌乳腺组织中则为12.50%,两者间具有高度显著性差异(P<0.01),PCNA在乳腺癌组织中的阳性表达率为78.43%,癌旁正常乳腺组织中则为8.33%,它们之间的差异有高度显著性(P<0.01),VEGF和PCNA的阳性表达率与乳腺癌病理学分级呈正相关,说明VEGF和PCNA阳性表达作为乳腺 辅助诊断指标。 相似文献
70.
李婕 《重庆工商大学学报(自然科学版)》2012,(7):64-70
水污染致癌作为环境公害犯罪的典型代表,应以以危险方法危害公共安全罪处罚。传统的条件说无法排除水污染以外的致癌因素,疫学因果关系要求被告人举证倒置,无法适用到中国的刑法领域。为达到"排除合理怀疑"的证明标准,需借助客观归责理论中的危险升高理论来进行环境公害案件的客观归责。现代刑法理论中的"故意"呈客观化趋势,可根据客观证据认定被告人主观上具有故意及证明被告人有不法认识可能性,从而完成环境公害案件的主观归责。 相似文献