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51.
FasL的表达在结直肠癌免疫逃逸中的意义   总被引:3,自引:0,他引:3  
目的研究结直肠癌中Fas配体(FasL)的表达及其在结直肠癌免疫逃逸中的意义。方法采用免疫组织化学染色法,检测80例结直肠癌组织中FasL表达及肿瘤浸润淋巴细胞(TIL)的数量。应用原位杂交法,检测80例结直肠癌组织连续切片的FasL的。RNA的表达。采用脱氧核糖核酸末端转移酶介导的缺口末端标记技术(TUNEL),对80例结直肠癌组织中凋亡的TIL及肿瘤细胞进行观察。结果80例结直肠癌组织FasL表达程度不等,不论是在同一组织切片不同部位或两组织切片间相比,FasL表达程度和范围都不均匀。FasL的mRNA的表达部位与FasL蛋白的表达部位相对应。FasL表达程度高的组织的TIL计数低于FasL表达低的组织(P〈0.05),同时其TIL凋亡指数高于FasL表达低的组织,而结直肠癌细胞的凋亡指数低于FasL表达程度低的组织(P〈0.01),TIL凋亡指数与胃癌细胞的凋亡指数呈负相关(r=-0.631,P〈0.01)。结论全占直肠癌细胞可通过表达FasL,诱导TIL发生凋亡,反击机体免疫系统,这可能是结直肠癌免疫逃避的重要机制之一。  相似文献   
52.
应用银染技术,对24例结肠腺癌Ⅱ级不典型增生,30例绒毛状腺瘤,14例绒毛状腺瘤Ⅲ级不典型增生和29例高分化管状腺癌进行银染核仁形成区嗜银蛋白(Ag-NORs)定量研究,观察Ag-NORs数量、形态、大小和分布在结肠肿瘤交界性病变中的表达.提示Ag-NORs四项指标定量研究对结肠脉瘤,特别是Ⅲ级不典型增生与绒毛状腺瘤之结肠癌前病变有较好的监测作用.  相似文献   
53.
OBJECTIVE: We reviewed recent literature to assess the impact of hospital caseload, surgeon's caseload and education on long-term outcome following colorectal cancer surgery. METHOD: We searched the MEDLINE and Cochrane Library databases for relevant literature starting from 1992. We selected hospital caseload, surgeon's caseload and surgeon's education, type of hospital, and surgeon's experience as variables of interest. Measures of outcome were recurrence-free survival and overall survival, and for rectal cancer frequency of permanent stoma. We reviewed the 34 studies according to tumour location: colonic cancer, rectal cancer, or colorectal cancer. We described the studies individually and performed a meta-analysis whenever it was considered appropriate. RESULTS: For colonic cancer, overall survival improved with increasing hospital caseload, odds ratio (OR) 1.22 [95% confidence interval (CI) 1.16-1.28], and surgeon's education. For rectal cancer, overall survival improved with increasing hospital caseload, OR 1.38 (95% CI 1.19-1.60), and, possibly by surgeon' education and experience. Cancer-free survival was strongly influenced by surgeon's education. The colostomy rate was less in high caseload hospitals, OR 0.76 (95% CI 0.68-0.85). For colorectal cancer, overall survival improved with surgeon's education. CONCLUSION: The data have provided evidence that long-term survival following colorectal cancer surgery in general improved significantly with increasing hospital caseload and surgeon's education.  相似文献   
54.
大肠癌肝转移射频消融后局部复发影响因素的分析   总被引:1,自引:0,他引:1  
目的 探讨射频消融(radiofrequency ablation,RFA)治疗大肠癌肝转移后局部肿瘤复发的风险因素。方法 回顾性研究213例347个肿瘤实施RFA治疗后局部复发的临床资料,对可能影响RFA局部治疗效果的临床因素进行统计学处理。结果 175例(82.2%)298个肿瘤(85.9%)得到CT或MRI随访资料。大肠癌肝转移灶RFA后肿瘤局部复发率为36.9%(110/298),局部复发的平均时间为16.4月(2~57个月)。单因素分析显示肝脏转移灶的部位、大小和射频针类型与肿瘤射频后的局部复发相关(P值分别为P=0.000,P=0.021和P=0.026),但Cox多因素分析则显示只有瘤大小和转移灶部位是大肠癌肝转移射频消融后局部复发的独立预后因素(χ^2=8.522,P=0.000;χ^2=1.321,P=0.022)。结论 肝脏肿瘤的大小和部位是RFA治疗效果的独立影响因素,正确的电极选择和布针是获得肿瘤完全坏死的关键。  相似文献   
55.
OBJECTIVE: An association between caseload and outcome has been reported for complex surgical procedures. We systematically reviewed recent literature to determine whether caseload and surgical speciality are associated with short-term outcome following colorectal cancer surgery. METHOD: We searched the MEDLINE and Cochrane Library databases for relevant publications starting in 1992. We selected hospital caseload and type, and surgeon's caseload, education and experience as variables of interest. Measures of outcome were postoperative morbidity, in-hospital and 30-day mortality, and for rectal cancer anastomotic leak. We stratified the 35 reviewed studies by tumor location: colonic cancer, rectal cancer, or colorectal cancer and described the studies individually. A meta-analysis was performed only when it was considered appropriate. RESULTS: For colonic cancer, postoperative morbidity was associated with surgeon's caseload and education. Postoperative mortality was strongly associated with hospital caseload (OR 0.64, 95% CI 0.55-0.73), and surgeon's caseload (OR 0.50, 95% CI 0.39-0.64). It was also influenced by surgeon's education and experience. For rectal cancer, we found no evidence of an association between the selected variables and short-term outcome, including frequency of anastomotic leak. For colorectal cancer, there was evidence for an association between postoperative morbidity and hospital caseload. CONCLUSION: Our review offers evidence for a positive association between high hospital caseload, surgeon's caseload, sub-speciality and experience and improved short-term outcome in colonic cancer surgery. We failed to find evidence of a relationship for rectal cancer surgery, possibly owing to methodological artifacts. No study reported an inverse relation.  相似文献   
56.
This paper reviews the literature on colorectal cancer from a sex and gender-based perspective. Colorectal cancer is a major cause of death in the developed world, with rates increasing in developing countries. Although described by some writers as an ‘equal opportunity’ disease, it presents more risk to men than women. Both biological, or sex-linked factors, and gender-linked factors play a part in the aetiology of the disease, while gender differences in the use of screening and treatment also help shape the mortality gap between women and men for this condition. Without an appreciation of the part played by sex and gender in the risk of colorectal cancer, and without a gender-sensitive approach to screening in particular, it is possible that the mortality gap between men and women for this condition will widen in the future.  相似文献   
57.
目的阐述在结直肠肿瘤多学科协作(MDT)诊治模式下,如何构建数据体系及其运作策略。方法阐明构建数据体系的原因,结合实践描述结直肠肿瘤数据体系的基本构成及如何支持数据体系的运行,探讨结直肠肿瘤MDT数据体系的价值反馈,并提出对数据体系建立未来的展望。结果通过会诊、随访、院内临床的支持及合理地实现MDT模式中信息化流程的建设,数据体系运行能正常进行。结论数据体系作为整个结直肠肿瘤MDT项目的基础,能够通过医疗模式的改变表现出医疗价值和社会价值。  相似文献   
58.
微生态肠内营养在结直肠癌患者围手术期的应用   总被引:2,自引:2,他引:0  
目的:探讨微生态肠内营养在结直肠癌患者围手术期应用中的疗效。方法:将90例结直肠癌患者随机分为3组:常规治疗组(RT)、肠内营养组(EN)及添加微生态制剂肠内营养组(EMN)。观察患者术中肠道清洁度以及术后排气时间、吻合口漏、感染情况以及菌群失调情况,并监测手术前后内毒素、CRP、TNF水平变化及淋巴细胞计数改变。结果:术后排气时间EN组及MEN组均早于RT组(P<0.05),而EMN组早于EN组(P<0.05);第1次排便后细菌油镜计数结果示EN组及MEN组均明显低于RT组(P<0.05),而EMN组低于EN组(P<0.05)。术后外周血内毒素及CRP水平EN组及MEN组均低于RT组(P<0.05),而EMN组低于EN组(P<0.05);外周血淋巴细胞计数EMN组较术前有所增加(P<0.05),其他两组无明显变化;TNF水平各组均高于术前水平(P<0.05)。肠腔清洁度、吻合口漏、切口感染率及腹腔感染率差异均无统计学意义(P>0.05)。结论:添加微生态制剂肠内营养能有效防治患者肠道菌群失调,增强机体免疫力,促进肠道功能恢复。  相似文献   
59.
Is anaemia relevant in the referral and diagnosis of colorectal cancer?   总被引:1,自引:0,他引:1  
OBJECTIVE: Current efforts to improve the outcome from colorectal cancer aim to shorten the delay between referral and diagnosis. Investigation of iron-deficiency anaemia has a high yield for the diagnosis of gastrointestinal malignancy and its presence is included in current referral guidelines. We explored the relationship between anaemia and colorectal cancer. METHOD: We reviewed hospital and laboratory database records of patients diagnosed with colorectal cancer between January 2003 and June 2004. The site of colorectal cancer was correlated with the presence of anaemia at the time of referral. Anaemia was defined according to local practice (Hb < 12.0 g/dl in females and <13.0 g/dl in males), compared with the threshold recommended in current national referral guidelines (Hb < 10 g/dl in females and <11 g/dl in males). RESULTS: Over 18 months, 143 patients were diagnosed with colorectal cancer. Anaemia was present in 48% of males and 50% of females using local practice and 24% of males and 16% of females using national referral guidelines. Those with right-sided and non-rectal cancers were significantly more likely to be anaemic than those with left-sided and rectal cancers, respectively. CONCLUSION: In approximately half of cases the diagnosis of colorectal cancer is not associated with anaemia. Anaemia is more common with proximal lesions but this is not a consistent finding. The current threshold for anaemia at which national guidelines suggest referral also appears to be insensitive.  相似文献   
60.
新辅助化疗对结直肠癌的作用   总被引:3,自引:0,他引:3       下载免费PDF全文
目的探讨短程5-FU/CF方案新辅助化疗对结直肠癌细胞凋亡、增殖和p53表达以及术后并发症和预后的影响。方法分别采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)和免疫组化SP法检测68例患者结直肠癌组织的细胞凋亡指数(AI)和ki-67增殖指数(PI)及凋亡相关基因p53的表达,并比较新辅助化疗组和对照组患者术后并发症的发生情况和预后情况。结果新辅助化疗组肿瘤细胞的AI均数为3.56%,明高于对照组的2.29%(P〈0.01),PI均数为22.60%明显低于对照组的33.60%(P〈0.01),p53阳性表达率为28.9%(11/38)明显低于对照组的56.7%(17/30)(P〈0.05)。两组中大肠癌细胞的AI与PI均呈负相关(r=-0.790,r=-0.663)(P〈0.01)。两组术后并发症的发生差异无显著性(P〈0.05)。两组的复发转移率和复发转移平均时间差异有显著性(P〈0.05)。结论短程5-FU/CF方案新辅助化疗可以显著诱导结直肠癌细胞凋亡,并抑制其增殖;降低结直肠癌组织p53的阳性表达率,而不增加术后并发症的发生,能延缓和减少结直肠癌术后的复发转移。  相似文献   
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