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81.
p53和p16在胆囊癌中的表达 总被引:5,自引:0,他引:5
目的探讨抑癌基因p53和p16改变对胆囊癌发生的作用。方法采用免疫组化方法检测34例胆囊癌和26例慢性胆囊炎标本中p53和p16的表达。结果慢性胆囊炎标本中p531例阳性,阳性率为3.9%。胆囊癌中p53有17例阳性,阳性率为50%。两者表达差异有显著性(P<0.001)。p16在慢性胆囊炎标本中有14例阳性,阳性率为53.8%,胆囊癌中29例阳性,阳性率为85.3%,明显高于慢性胆囊炎(P<0.02)。结论p53过表达与胆囊癌发生之间存在一定的联系,但对胆囊癌的发展、侵袭影响不大。p16在胆囊癌发生中可能受某些癌基因的反馈调节而过度表达,其作用机制尚不十分清楚。 相似文献
82.
目的探讨胆囊癌与妊娠的关系.方法采用全人群病例对照研究,研究对象为1997年6月1日~2001年5月31日期间确诊、年龄在35~74岁的上海市区女性胆囊癌269例以及按年龄(5岁一组)频数配对的538名人群对照,采用非条件lo-gistic回归模型分析妊娠与胆囊癌的关系.结果胆囊癌合并胆石症者中,与妊娠次数≤2次者比较,妊娠次数(3次,4次,5次及≥6次)的各组调整OR分别为1.33(95%CI:0.59-2.99),1.34(95%CI:0.58-3.11),1.39(95%CI:0.57-3.43)和2.67(95%CI:1.12-6.41),趋势检验P=0.03.结论多次妊娠可能通过胆石症影响胆囊癌的发生,生育因素导致的女性体内雌、孕激素水平的升高可能在胆囊癌病因学中起一定的作用. 相似文献
83.
白藜芦醇抑制胆囊癌细胞生长与诱导细胞凋亡的实验研究 总被引:5,自引:1,他引:5
目的:探讨白藜芦醇(Res)对胆囊癌细胞(GBC)和正常成纤维细胞(3T3)体外增殖的影响,进而观察Res对GBC和3T3细胞凋亡的影响.方法:MTT法测定肿瘤细胞生长抑制率;流式细胞术分析细胞周期,检测细胞凋亡;SABC法检测细胞bcl-2、c-myc、p53蛋白表达.结果:Res呈浓度依赖性抑制GBC细胞的生长与增殖(P<0.01),抑制率最高可达54%.Res能明显诱导GBC细胞凋亡,凋亡率最高为30.52%;处理组较对照组G1期细胞由34.88%上升至55.47±3.95%,S期细胞减少8.41%~17.54%,呈明显的G0/G1期阻滞现象.GBC细胞的bcl-2、c-myc基因蛋白表达降低,而p53基因蛋白表达增强.结论:Res能通过诱导GBC细胞凋亡而抑制其生长与增殖,但对3T3细胞无此作用. 相似文献
84.
目的分析不同手术方式对Ⅳ期胆囊癌预后的影响.方法对1997年6月~2001年5月间上海市172例Ⅳ期胆囊癌病例进行临床病理分析,并对获得随访的164例的预后与手术方式的关系进行探讨.数据分析采用Kaplan-Meier法.结果 172例中未手术者44例(25.6%),手术者128例(74.4%),其中包括单纯胆囊切除术45例(35.1%)、胆囊癌根治性切除术17例(13.3%)、胆囊癌扩大根治性切除术5例(3.9%)和剖腹探查术61例(47.7%).在行根治性切除者中,Ⅳa和Ⅳb期的1年生存率分别为69.2%和40.7%,明显好于胆囊未切除或单纯切除者,在Ⅳa和Ⅳb期中各有2例存活期超过5年.结论有选择地进行Ⅳ期胆囊癌病例根治性或扩大根治性手术,有助于改善预后. 相似文献
85.
《Diagnostic Histopathology》2014,20(1):19-29
Most mesenchymal polyps are encountered in the colorectum but some characteristically arise in the oesophagus and stomach. Small bowel polyps are not often sampled but many of the types found in the other locations can be found in the small intestine and are covered elsewhere in this volume. Generally mesenchymal lesions of the tubular gastrointestinal tract that present as polyps are centred in the mucosa or submucosa. However, some lesions that are typically centreed in the muscularis propria are included since they are often confused with superficial lesions. Often the issues in interpreting such lesions revolve around whether the tumour is a gastrointestinal stromal tumour and whether it is a syndromic or sporadic, which has been addressed particularly for neural lesions. 相似文献
86.
Pamela L. Strissel Matthias Ruebner Falk Thiel David Wachter Arif B. Ekici Friedericke Wolf Franziska Thieme Klemens Ruprecht Matthias W. Beckmann Reiner Strick 《Oncotarget》2012,3(10):1204-1219
Endometrial carcinoma (EnCa) is the most common invasive gynaecologic carcinoma. Over 85% of EnCa are classified as endometrioid, expressing steroid hormone receptors and mostly involving pathological prestages. Human endogenous retroviruses (ERV) are chromosomally integrated genes, account for about 8% of the human genome and are implicated in the etiology of carcinomas. The majority of ERV envelope (env) coding genes are either not present or not consistently represented between common gene expression microarrays. The aim of this study was to analyse the absolute gene expression of all known 21 ERV env genes including 19 codogenic and two env genes with premature stop codons in EnCa, endometrium as well as in hyperplasia and polyps. For EnCa seven env genes had high expression with >200 mol/ng cDNA (e.g. envH1-3, Syncytin-1, envT), two middle >50 mol/ng cDNA (envFc2, erv-3) and 12 low <50 mol/ng cDNA (e.g. Syncytin-2, envV2). Regarding tumor parameters, Syncytin-1 and Syncytin-2 were significantly over-expressed in advanced stage pT2 compared to pT1b. In less differentiated EnCa Syncytin-1, erv-3, envT and envFc2 were significantly over-expressed. Syncytin-1, Syncytin-2 and erv-3 were specific to glandular epithelial cells of polyps, hyperplasia and EnCa using immunohistochemistry. An analysis of 10 patient-matched EnCa with endometrium revealed that the ERV-W 5'' long terminal repeat regulating Syncytin-1 was hypomethylated, including the ERE and CRE overlapping MeCP2 sites. Functional analyses showed that 10 env genes were regulated by methylation in EnCa using the RL95-2 cell line. In conclusion, over-expressed env genes could serve as indicators for pathological pre-stages and EnCa. 相似文献
87.
Colorectal endoscopic submucosal dissection: Systematic review of mid‐term clinical outcomes
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Nisha Patel Kinesh Patel Hutan Ashrafian Thanos Athanasiou Ara Darzi Julian Teare 《Digestive endoscopy》2016,28(4):405-416
With a drive towards minimally invasive surgery, endoscopic submucosal dissection (ESD) is now gaining popularity. In a number of East Asian countries, ESD is now the treatment of choice for early non‐metastatic gastric cancer, but the outcomes of ESD for colorectal lesions are unclear. The present review summarizes the mid‐term outcomes of colorectal ESD including complication and recurrence rates. A systematic literature search was done in May 2014, identifying 20 publications reporting the outcomes of colorectal ESD which were included in this review. En‐bloc resection rates, complete (R0) resection rates, endoscopic clearance rates, complication and recurrences rates were analyzed. Statistical pooling was done to calculate weighted means using random effects modeling. Twenty studies reporting the outcomes of 3060 colorectal ESD procedures were reported. Overall weighted en‐bloc resection rate was 89% (95% CI: 83–94%), R0 resection rate 76% (95% CI: 69–83%), endoscopic clearance rate 94% (95% CI: 90–97%) and recurrence rate 1% (95% CI: 0.5–2%). Studies that followed up patients for over 1 year were found to have an en‐bloc resection rate of 91% (95% CI: 86–96%), R0 resection rate of 81% (95% CI: 75–88%), endoscopic clearance rate 93% (95% CI: 90–97%) and recurrence rate of 0.8% (95% CI: 0.4–1%). Colorectal ESD can be carried out effectively and safely with a 1% recurrence rate. Further studies with longer follow‐up periods are required to determine whether colorectal ESD is a viable alternative to conventional surgical therapy. 相似文献
88.
目的比较表面麻醉纤维喉镜与全麻显微支撑喉镜对不同类型声带息肉(VCP)摘除的临床疗效。方法以2007年11月至2012年10月芜湖市第一人民医院收治的164例VCP患者作为研究对象,按照随机数字表法分为两组,表麻纤维喉镜组66例,采用表面麻醉纤维喉镜下VCP摘除术(广基VCP27例、带蒂VCP39例),全麻显微支撑喉镜组98例,采用全麻显微支撑喉镜下VCP摘除术(广基VCP50例、带蒂VCP48例),比较两组治疗效果及术后随访期间并发症发生情况。结果表麻纤维喉镜组手术时间显著短于全麻显微支撑喉镜组[(35.6±12.3)min vs(46.5±17.6)min,P<0.05]。全麻显微支撑喉镜组与表麻纤维喉镜组对带蒂VCP有效率差异无统计学意义(95.8%vs97.4%,P>0.05);但全麻显微支撑喉镜组对广基VCP有效率显著高于表麻纤维喉镜组(94.0%vs81.5%,P<0.05)。全麻显微支撑喉镜组不良并发症发生率与表麻纤维喉镜组比较,差异无统计学意义(7.1%vs 4.5%,P>0.05)。结论表麻纤维喉镜与全麻显微支撑喉镜下VCP摘除术各有优点及局限,临床上应综合考虑以选择最优的治疗方案。 相似文献
89.
IntroductionExtracorporeal shockwave lithotripsy (ECSWL) for gallstones is rarely used due to high recurrence rates, but has been reported to be effective in some circumstances.Presentation of caseWe describe a case of a failed attempt at laparoscopic cholecystectomy due to gallbladder contraction and complete obliteration of Calot’s triangle. Cholecystotomy was performed to remove all visible stones, and completed by a subtotal cholecystectomy and closure of the gallbladder remnant. The patient remained symptomatic due to a residual stone in the Hartmann’s pouch. ECSWL was attempted to fragment the stone; however, follow-up imaging showed persistence of the calculus.DiscussionLiterature review shows that ECSWL for multiple gallbladder stones has a low success rate. Even if a stone is successfully fragmented, a diseased gallbladder remnant seems incapable of expelling the fragments. Without completion endoscopic clearance, therefore, the treatment is considered incomplete.ConclusionOur case suggests that ECSWL is ineffective in management of residual gallbladder stones after failed cholecystectomy. 相似文献
90.
Challenging diagnostic issues in adenomatous polyps with epithelial misplacement in bowel cancer screening: 5 years’ experience of the Bowel Cancer Screening Programme Expert Board
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Rebecca K L Griggs Marco R Novelli D Scott A Sanders Geraint T Williams Philip Quirke Neil A Shepherd 《Histopathology》2017,70(3):466-472
The diagnostic difficulties of differentiating epithelial misplacement from invasive cancer in colorectal adenomatous polyps have been recognised for many years. Nevertheless, the introduction of population screening in the UK has resulted in extraordinary diagnostic problems. Larger sigmoid colonic adenomatous polyps, which are those most likely to show epithelial misplacement, are specifically selected into such screening programmes, because these polyps are likely to bleed and screening is based on the detection of occult blood. The diagnostic challenges associated with this particular phenomenon have necessitated the institution of an ‘Expert Board’: this is a review of the first five years of its practice, during which time 256 polyps from 249 patients have been assessed. Indeed, the Expert Board contains three pathologists, because those pathologists do not necessarily agree, and a consensus diagnosis is required to drive appropriate patient management. However, this study has shown substantial levels of agreement between the three Expert Board pathologists, whereby the ultimate diagnosis has been changed, from that of the original referral diagnosis, by the Expert Board for half of all the polyps, in the substantial majority from malignant to benign. In 3% of polyp cases, the Expert Board consensus has been the dual diagnosis of both epithelial misplacement and adenocarcinoma, further illustrating the diagnostic difficulties. The Expert Board of the Bowel Cancer Screening Programme in the UK represents a unique and successful development in response to an extraordinary diagnostic conundrum created by the particular characteristics of bowel cancer screening. 相似文献