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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   
73.
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   
74.
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   
75.
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   
76.
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   
77.
摘要: 目的 研究胰腺癌患者血清肿瘤相关胰蛋白酶原-2在胰腺癌初筛中的意义。方法 收集北京军区总医院23例胰腺癌住院患者的治疗前血清标本和35 例正常对照者(健康体检者)血清标本。采用酶联免疫吸附法检测血清胰蛋白酶原-2含量。结果 血清胰蛋白酶原-2含量在正常对照组中位数为0.8ug/L,四分位间距0.6~1.2μg /L; 胰腺癌患者中位数为13.8μg /L,四分位间距2.3~60.7μg/L。胰腺癌组和正常对照组血清胰蛋白酶原-2水平有统计学差异( P<0.01) 。以1.85ug /L为临界值作为诊断胰腺癌界定值的敏感度为91.4%,特异度为95.7%。结论 血清胰蛋白酶原-2检测可作为胰腺癌的一种初筛试验。  相似文献   
78.
A major portion of the mammalian genome is transcribed to produce large numbers of noncoding RNAs(ncRNAs).During the past decade,the discovery of small RNAs,including the microRNAs(miRNA) and small interfering RNAs(siRNA),has led to important advances in biology.The breadth of the ncRNA field of study has substantially expanded and many recent results have revealed a range of functions that can be attributed to the miRNAs and other ncRNAs.For example,H19 RNA,HOTAIR RNA,transcribed ultraconserved regions(T-UCRs),natural antisense RNA,transfer RNA and mitochondrial noncoding RNA have been suggested to play important roles in cancers and other diseases as well as in diverse cellular processes.In this review,we focus on the current status of several classes of ncRNAs associated with cancer with the emphasis on those that are not microRNAs.  相似文献   
79.
通过腔内超声估价直肠癌浸润情况。方法;疑有直肠癌患者21例,术前行直肠腔内超声检查。结果;经手术和是证实为直肠癌患者21例,直肠腔内超声癌灶检出率为90.5%,超声判断癌灶浸润深度与病理诊断符合率为94.7%。结论:直肠腔内超声检查是判断直肠癌浸润深度,侵及肠壁周径,纵长长度的理想手段。  相似文献   
80.
研究莪术油影响人胃癌细胞SGC-7901增殖及凋亡的机制。采用台盼蓝拒染法检测不同剂量莪术油对胃癌细胞SGC-7901的生长抑制率;光学显微镜观察细胞的形态学变化;琼脂糖凝胶电泳检测细胞DNA片段化情况;流式细胞术检测细胞线粒体膜电位的改变、细胞凋亡率以及细胞周期分布。实验结果表明:作用48h时,最佳浓度为110μg/mL,IC50值为104.958μg/mL。DNA电泳可见有梯状条带出现,流式细胞术法显示有凋亡峰出现。莪术油可诱导胃癌SGC-7901细胞凋亡。  相似文献   
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