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51.
目的:探讨胆管癌患者血管内皮生长因子C和D(vascular endothelial growth factor-C and-D,VEGF-C and VEGF-D)在胆管癌组织中的表达及其与肿瘤淋巴结转移的关系。方法:应用免疫组化SABC法及Real-time PCR法检测57例胆管癌组织和正常胆管组织中VEGF-C、VEGF-D蛋白及其mRNA的表达。结果:胆管癌组织VEGF-C和VEGF-D表达明显高于正常胆管组织(P<0.01),其中淋巴结转移组VEGF-C、VEGF-D的表达与淋巴结未转移组间统计学差异显著(P<0.05)。VEGF-C和VEGF-D在胆管癌组织中的表达与淋巴结转移有关(P<0.01)。结论:胆管癌细胞非摄入性高表达的VEGF-C和VEGF-D与淋巴结转移密切相关,可作为评估胆管癌患者预后的重要参考指标。  相似文献   
52.
CD4+8 T lymphocytes with potent antitumor activity in vivo were obtained in peritoneal exudate cells by immunizing mice with irradiated MM48 tumor cells admixed with OK-432. These immune CD4+ T cells were used in adoptive immunotherapy for prevention of lymph node metastases after removal of the primary tumor. Complete cure of metastases was obtained by adoptive transfer of CD4+ T cells admixed with irradiated MM48 tumor cells, but not by CD4+ T cells alone. To analyze the curative effect of admixing tumor cells on the prevention of metastases, a model of 1-day tumor inoculated with macrophages was used. Administration of immune CD4+ T cells alone resulted in the regression of local tumor in more than half of the mice, although all of them eventually died of lymph node metastases. On the other hand, adoptive transfer of immune CD4+ T cells plus irradiated tumor cells resulted in the complete regression of local tumors in all the mice, which survived without any sign of metastasis. The curative effect of the immune CD4+ T cells obtained by admixing irradiated tumor cells was tumor-specific. Macrophages induced by OK-432 (tumoricidal), implanted together with tumor, assisted tumor regression more than did macrophages elicited by proteose peptone (nontumoricidal) in the same adoptive transfer system. Administration of recombinant interleukin-2 instead of stimulant tumor cells did not enhance, but rather eliminated the constitutive antitumor activity of CD4+ T cells. On the other hand, exogenous recombinant interleukin-1 was more effective in the enhancement of antitumor activity of the CD4+ T cells as compared with stimulant tumor cell administration. In this case, the activating states of macrophages at the implanted tumor site had no influence on the therapeutic efficacy. A possible role of macrophages for induction of tumor-specific cytotoxic T cells that were mediated by tumor-specific CD4+ T cells is discussed.  相似文献   
53.
Methylation-sensitive restriction endonuclease analysis (MSRA) followed by polymerase chain reaction (PCR) have been used to estimate the methylation level of 13 CpG dinucleotides in the promoter region of the putative suppressor gene RASSF1A (3p21.31) in squamous cell carcinomas of the uterine cervix (SCCs) carrying human papillomavirus (HPV) types 16, 18, and related types. Methylation of 3 to 13 CpG pairs has been found in 64% (25 out of 39) tumor DNA samples, 22% (2 out of 9) DNA samples from morphologically normal tissues adjacent to the tumor (P = 0.0306), and two out of three DNA samples from peripheral blood leukocytes of carcinoma patients. These CpG pairs are not methylated in the DNA of leukocytes of healthy donors (0 out of 10). The methylation level of the RASSF1A promoter region studied in tumors of the patients with regional lymph node metastases is significantly higher than in tumors of the patient that have no metastases (P = 8.5 × 10–12). The methylation frequency of gene RASSF1A is two times higher than the frequency of hemi- and homozygous deletions in the chromosome 3 region where the gene is located. The data obtained indicate that methylation is one of the main mechanisms of the RASSF1A gene inactivation in HPV-positive human cervical tumors. The methylation of this gene may be an early event in the genesis of cervical tumors, the methylation level increasing with tumor progression.  相似文献   
54.
摘要 目的:探讨动态对比增强磁共振(DCE-MRI)联合弥散加权成像(DWI)诊断直肠癌术前T、N分期和系膜淋巴结良恶性的价值。方法:收集2017年2月至2019年10月中国医科大学附属本溪中心医院和中国医科大学附属盛京医院接诊的80例直肠癌患者,均进行常规核磁共振成像(MRI)、DCE-MRI、DWI扫描,获得DCE-MRI、DWI定量参数[转运常数(K trans )、细胞外血管外空间的体积分数(V e )、速率常数(K ep )、表观扩散系数(ADC)],比较不同T、N分期、不同性质系膜淋巴结DCE-MRI、DWI参数,及其对T、N分期和系膜淋巴结性质的诊断效能。结果:直肠癌癌灶K trans 、 K ep 、V e 高于正常肠壁,ADC低于正常肠壁(P<0.05)。TNM分期为TⅢ~Ⅳ期的患者K trans 、 K ep 、V e 高于TⅠ~Ⅱ期,ADC低于TⅠ~Ⅱ期(P<0.05);TNM分期为N1期的患者K trans 、K ep 、V e 高于N0期,ADC低于N0期(P<0.05)。联合诊断的灵敏度、特异度、阳性预测值、阴性预测值较高。结论:DCE-MRI联合DWI对直肠癌术前T、N分期、系膜淋巴结性质诊断价值较高。  相似文献   
55.
隗溟  李冬霞 《生态学报》2013,33(22):7098-7107
本研究选用两个籼稻杂交品种西农优1号和冈优725,采用人工去蘖形成分蘖初期的早发、中发、迟发三个处理,在群体条件下研究分蘖和生产力的补偿能力。本研究发现,迟发处理高节位群的分蘖补偿能力最明显,但绝对补偿量小。迟发处理高节位群的生长势、有效分蘖倍数增加,抽穗期单茎叶面积有增加的趋势,但抽穗期有效穗数、叶面积系数降低;迟发处理冠层光分布增加,叶绿素、蛋白质含量提高,叶片细胞内保护酶类(Superoxide dismutase, SOD、catalase,CAT)活性下降慢,叶片衰老慢,但是漏光率增加,截光率下降;迟发处理净光合生产率(Net assimulation rate, NAR)增加,同化物分配合理,经济系数有增加的趋势,但物质积累速度(Crop growth rate ,CGR)和干物质生产量减少。在本实验条件下,早发与中发处理的经济产量差异不显著,但早发与迟发处理的经济产量差异达极显著。本研究结果表明大苗秧对生物、非生物因素胁迫,如本田前期一定程度的人工去蘖,具有一定的分蘖补偿能力。  相似文献   
56.
摘要 目的:探讨超声检查参数联合血清血管内皮生长因子(VEGF)、甲状腺球蛋白(Tg)、半乳糖血凝素-1(Gal-1)对于甲状腺癌的临床诊断价值及其与淋巴结转移的关系。方法:回顾性分析2017年6月至2020年6月入我院就诊的158例甲状腺肿瘤患者的临床资料。77例甲状腺癌患者纳入恶性组,81例甲状腺腺瘤患者纳入良性组,比较两组的超声检查参数及血清VEGF、Tg、Gal-1水平;此外,恶性组患者亚分组为淋巴结转移组(n=51)和无淋巴结转移组(n=26),比较两组超声检查参数及血清VEGF、Tg、Gal-1水平。以受试者工作特征(ROC)曲线分析超声检查参数联合血清VEGF、Tg、Gal-1对甲状腺癌的诊断效能。采用Sprearman相关系数分析各指标水平变化与甲状腺癌患者发生淋巴结转移的相关性。结果:恶性组患者的血管化指数(VI)、血流指数(FI)及血清VEGF、Tg、Gal-1水平均高于良性组患者(P<0.05);淋巴转移组患者的VI、FI及血清VEGF、Tg、Gal-1水平均高于无淋巴结转移组患者(P<0.05);超声检查参数VI、FI联合血清VEGF、Tg、Gal-1诊断甲状腺癌的曲线下面积为0.933、敏感度为85.50%、特异度为80.00%,均明显高于五项指标单独检测。Spearman相关性分析结果显示,超声检查参数VI、FI以及血清VEGF、Tg、Gal-1与甲状腺癌患者淋巴结转移均呈正相关(P<0.05)。结论:联合检测超声检查参数VI、FI及血清VEGF、Tg、Gal-1对甲状腺癌有较高的早期诊断价值,且上述指标均与患者淋巴结转移密切相关。  相似文献   
57.
目的:探讨食管癌组织微小RNA-21(miR-21)、微小RNA-182(miR-182)表达与临床病理特征及预后的关系。方法:选择2010年10月至2014年2月期间在我院治疗的120例食管癌患者为研究对象,采集患者的食管癌组织及癌旁组织,采用荧光定量PCR检测组织中miR-21、miR-182表达量,采用Kaplan-Meier法分析患者生存情况。结果:与癌旁组织相比,食管癌组织中miR-21、miR-182表达量明显升高(P<0.05)。食管癌组织中miR-21、miR-182表达均与TNM分期和淋巴结转移相关(P<0.05)。miR-21低表达患者的5年生存率明显高于高表达患者(P<0.05),miR-182低表达患者的5年生存率明显高于高表达患者(P<0.05)。结论:miR-21、miR-182表达量在食管癌中上调,与食管癌TNM分期和淋巴结转移相关。miR-21高表达以及miR-182高表达患者5年生存率下降,检测miR-21、miR-182表达量在食管癌患者预后预测中具有一定临床意义。  相似文献   
58.
Summary A recent study of lymph nodes of the rat showed that they are morphologically and physiologically compartmentalized. A compartment of a node includes a portion of subcapsular sinus into which the lymph, entering via the related afferent lymphatic opening, is filtered. The study also showed that colloidal carbon injected locally in a small dose becomes predominantly associated with the areas of the inner wall of the subcapsular sinus that cover the extrafollicular zone of the peripheral cortex. Little carbon is seen over the folliculo-nodules (follicles with a nodule or germinal center). The question arose as to whether drained natural substances, as antigens and antibodies, follow the same pattern of distribution in the subcapsular sinus as the carbon. Therefore, small doses of fluorescein isothyocyanate (FITC)-conjugated antigens were injected locally into normal rats whose own antibodies in the nodes were stained by immunofluorescence. The pattern of distribution of the antigens in the draining nodes was found to be the same as that of the carbon. Furthermore, the lymph-carried antibodies of the rats were found to follow the same pattern. The morphological basis for such a pattern is explained. The results are further discussed with regard to the probable normal entry route of lymph-carried antigens in the parenchyma of nodes.Supported by a grant from the Université de Montréal  相似文献   
59.
目的:探讨甲状腺乳头状癌发生颈部淋巴结转移的危险因素。方法:回顾性分析我院自2017年1月至2017年5月手术治疗甲状腺乳头状癌病人177例的临床资料,采用卡方检验、t检验及logistic回归分析甲状腺乳头状癌发生颈部淋巴结的危险因素。结果:甲状腺乳头状癌淋巴结转移率为45.8%,术后并发症发生率为6.2%,淋巴结转移组较未转移组年龄更小、癌结节更大(P0.05),两组比较性别无统计学差异(P0.05),0.5 cm癌结节≤1 cm组较癌结节≤0.5 cm组更易出现淋巴结转移(P0.05),年龄大于45岁、癌结节≤0.5 cm的患者,9.6%发生淋巴结转移。Logistic回归分析提示年龄、癌结节大小是淋巴结转移的独立危险因素(P0.05)。结论:年龄、癌结节大小是淋巴结转移的独立危险因素,年龄越小、癌结节越大的甲状腺乳头状癌患者,越容易出现颈部淋巴结转移。  相似文献   
60.
In the present study T lymphocytes isolated from a metastatic lymph node (T-LNL) of a melanoma patient have been cloned. In the attempt to verify whether T-LNL may acquire in vitro functional activities in the absence of tumour-associated antigens, they were cloned utilizing allogeneic lymphocytes as feeder cells. Nineteen clones generated from T-LNL proved to be CD4+ and, among these, five were able to kill autologous and allogeneic human melanoma cells in HLA-class-II-restricted way. On the basis of their cytokine production, these CD4+ cytolytic T-LNL clones were shown to belong to the Th0 subset and three of them expersseed the V17 chain of the T cell receptor. These results suggest the presence of melanomaspecific but functionally inactive lymphocytes with T cell receptor oligoclonality in the lymph node environment. These specific T cells may acquire in vitro the capacity to kill autologous and allogeneic tumours without any induction by autologous melanoma cells.  相似文献   
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