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41.
目的 分选、鉴定人胰腺癌干细胞,运用基因芯片技术分析其差异性基因的表达.方法 运用流式分选技术分选胰腺癌干细胞(CD24+CD44+ESA+),NOD/SCID鼠移植瘤试验进行肿瘤干细胞特性鉴定.采用Affymetrix U133 plus2.0人类全基因组表达谱芯片对胰腺癌干细胞和非干细胞进行差异基因筛选.结果 分选得到人胰腺癌CD24+CD44+ESA+亚群细胞,占所有细胞的0.8%;5×103个CD24+CD44+ESA+细胞就能成瘤(2/4),而阴性细胞1×105才能成瘤(1/4);CD24+CD44+ESA+具有一定的自我更新和分化能力.基因芯片杂交获得6553(11.99%)条差异基因,胰腺癌干细胞中5255(9.61%)条上调表达,1298(2.37%)条下调表达.其中差异基因涉及细胞凋亡、细胞周期、代谢、细胞线粒体结构和耐药等多个方面.结论 胰腺癌于细胞具有自身特征性基因表达谱,为进一步从干细胞层面研究胰腺癌发病机制及靶向治疗奠定基础. 相似文献
42.
目的 探讨术中氩靶向冷冻治疗系统(即氩氦刀)治疗晚期胰腺癌的安全性及疗效。方法 2001-2002年期间8例晚期胰腺癌使用了术中氩氦刀治疗。结果 8例晚期胰腺癌病人中,平均生存期为8.6个月,1例目前仍然存活。5例腹痛病人,3例完全缓解,2例部分缓解;1例腰背痛病人,疼痛部分缓解。结论 术中氩氦刀治疗尽管不能明显延长晚期胰腺癌病人的平均生存期,但能明显缓解病人的疼痛,提高病人的生活质量,仍不失为一种有效的晚期胰腺癌的姑息治疗方法。 相似文献
43.
Traditionally the drainage of pancreatic pseudocysts has been carried out operatively, forming a cystenterostomy. A simple endoscopic method of forming a pancreatic cystogastrostomy with laser is presented. This procedure does not require a general anesthetic, is safe, and allows resolution of symptoms. 相似文献
44.
S. Rosewicz E. O. Riecken Priv.-Doz. Dr. med B. Wiedenmann 《Journal of molecular medicine (Berlin, Germany)》1992,70(3-4):205-209
Summary Secretory vesicles of both the exocrine and the endocrine pancreas have been isolated and characterized in molecular terms from pancreatic tissue and primary cell cultures. Studies on pancreatic secretory processes could be further facilitated by the use of permanent cell lines that respond to secretory stimuli with a regulated secretory response. We now present biochemical, morphological and secretory studies on the rat pancreatic acinar cell line AR42J. This cell line is characterized by the presence of digestive enzyme-containing dense core vesicles, which are released in response to cholecystokinin. In addition, we present evidence that these cells also contain small neuroendocrine-specific vesicles, as evidenced by the expression of the neuroendocrine-specific vesicle proteins synaptophysin and S.V.2. Corresponding to these mixed exocrine-neuroendocrine features, we also found considerable amounts of the neurotransmitters glycine, glutamine and gammaaminobutyric acid (GABA), as well as the rate-limiting enzyme in GABA synthesis, glutamic acid decarboxylase (GAD) (EC 4.1.1.15) expressed in these cells. We demonstrated a specific uptake mechanism for radioactively-labelled GABA by these cells. In addition, GABA was released from intracellular storage pools by nicotinic receptor stimulation or membrane depolarization. In summary, AR42J cells represent the first amphicrine pancreatic cell line with the combined expression of exocrine and neuroendocrine secretory organelles, both of which follow a regulated secretory pathway in response to various secretory stimuli.Abbreviations DCV
dense core vesicles
- GABA
gammaaminobutyric acid
- SDS-PAGE
sodium dodecyl sulphate polyacrylamide gel electrophoresis 相似文献
45.
VEGF-C和VEGF-D蛋白表达在胰腺癌淋巴转移中的意义 总被引:1,自引:1,他引:0
目的探讨胰腺癌中VEGF-C、VEGF-D蛋白表达与淋巴结转移之间的相关关系,阐明癌周淋巴管增生在胰腺癌淋巴转移中的作用及意义。方法免疫组化检测30例胰腺癌组织中VEGF-C、VEGF-D的表达及其与临床病理、淋巴结转移的关系。结果胰腺癌VEGF-C、VEGF-D蛋白表达阳性率分别为73%(22/30)、57%(17/30),肿瘤周边部位显著高于肿瘤中心部位,其表达与肿瘤的部位、分化程度、组织学类型无关,与肿瘤的TNM分期有关,Ⅲ~Ⅳ期显著高于Ⅰ~Ⅱ期。在VEGF-C、VEGF-D蛋白阳性组,淋巴结转移均显著增多。结论VEGF-C和VEGF-D与诱导胰腺癌淋巴管生成,促进肿瘤细胞淋巴道转移有关。 相似文献
46.
恶性梗阻性黄疸伴急性化脓性胆管炎一期行胰十二指肠切除术的可行性分析 总被引:2,自引:0,他引:2
目的对恶性梗阻性黄疸伴急性化脓性胆管炎一期行胰十二指肠切除术进行可行性分析。方法回顾分析我院1999年至2004年施行PD手术治疗恶性梗阻性黄疸病人128例,其中,PD手术治疗恶性梗阻性黄疸伴Asc24例(A组),PD手术治疗不伴有Asc病例104例(B组)。术前按Knaus法计算每例APACHEⅢ评分,对比分析两组术后并发症的发生率和死亡率,以及APACHEⅢ不同计分段下死亡率的差异。结果A组术后并发症发生率为45.8%,死亡率8.3%;B组术后并发症发生率为34.6%,死亡率7.7%。两组术后并发症发生率有显著性差异(P〈O.05),死亡率无显著性差异(P〉O.05)。APACHEⅢ计分段分别为40分以下、41~70分、71分以上统计死亡率,两组死亡率差异无显著性(P〉O.05),组内比较,不同计分段死亡率有显著性差异(P%0.05)。结论恶性梗阻性黄疸伴ASC病例术前全面和客观的评估、及时的手术探查和决断、术中的精细操作和围手术期的综合处理是保证一期PD术良好预后的决定因素。 相似文献
47.
18F-FDG PET/CT和增强CT对胰腺病变定性诊断的价值比较 总被引:1,自引:1,他引:0
目的评价^18F-脱氧葡萄糖(FDG)PET/CT对胰腺良、恶性病变定性诊断的价值。方法对15例胰腺恶性病变,6例良性病变患者行全身^18F-FDGPET/CT和增强CT检查,根据PET、增强CT和PET/CT图像上的表现分别诊断,并将结果进行比较。结果PET和PET/CT准确诊断全部恶性病变,而增强CT准确诊断全部良性病变。PET和PET/CT在6例良性病变诊断中分别显示2例和1例假阳性,而增强CT在15例恶性病变中有2例假阴性,但在上述3种诊断方法中分别出现的假阳性或假阴性都得到了相互间的纠正。增强CT、PET和PET/CT三者在诊断胰腺恶性肿瘤上的准确性分别为90.5%,90.5%和95.2%。此外,PET/CT比增强CT检出了更多的肝脏、淋巴结和骨转移灶;两者检出病灶数量分别为35,41,9和16,24,3个。结论PET/CT在胰腺良、恶性病变定性诊断上有价值,PET/CT和增强CT联合应用有利于进一步提高对胰腺恶性肿瘤的诊断和分期准确性。 相似文献
48.
Everson L. A. Artifon Airton Z. Rodrigues Sergio Marques Bhawna Halwan Paulo Sakai Claudio Bresciani Atul Kumar 《Journal of gastrointestinal surgery》2007,11(12):1686-1691
Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate
diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required
do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may
be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents
at the same time as the initial laparoscopy.
Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment
of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome
measure was complications rates.
Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor
in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were
deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic
exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures
median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was
3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy
was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction,
and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal
anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified:
one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total
of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications.
Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This
option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct. 相似文献
49.
P. O. Berberat H. Ingold A. Gulbinas J. Kleeff M. W. Müller C. Gutt M. Weigand H. Friess M. W. Büchler 《Journal of gastrointestinal surgery》2007,11(7):880-887
Concepts in “fast-track” surgery, which provide optimal perioperative care, have been proven to significantly reduce complication
rates and decrease hospital stay. This study explores whether fast-track concepts can also be safely applied and improve the
outcomes of major pancreatic resections. Perioperative data from 255 consecutive patients, who underwent pancreatic resection
by means of fast-track surgery in a high-volume medical center, were analyzed using univariate and multivariate models. Of
the 255 patients, 180 received a pancreatic head resection and 51 received distal, 15 received total, and 9 received segmental
pancreatectomies. The patients were discharged on median day 10 with a 30-day readmission rate of 3.5%. The in-hospital mortality
was 2%, whereas medical and surgical morbidities were 17 and 25%, respectively. Fast-track parameters, such as first stools,
normal food, complete mobilization, and return to normal ward, correlated significantly with early discharge (p < 0.05). Patients’ age, operation time, and early extubation proved to be independent factors of early discharge, shown through
multivariate analysis (odds ratio: 4.0, 2.0, and 2.8, respectively; p < 0.05). Low readmission, mortality, and morbidity rates demonstrate that fast-track surgery is in fact feasible and safe
and promotes earlier discharge without compromising patient outcomes. 相似文献
50.
Michael B. Farnell Gerard V. Aranha Yuji Nimura Fabrizio Michelassi 《Journal of gastrointestinal surgery》2008,12(4):651-656
With improvements in the safety of Whipple resection in recent decades, surgeons have continued to explore the role of more
extensive lymphadenectomy in hope of improving long-term survival. A systematic literature search of level I evidence addressing
the role of the extent of lymphadenectomy was undertaken. Only reports of prospective, randomized controlled trials comparing
pancreaticoduodenectomy with standard lymphadenectomy to pancreaticoduodenectomy with extended lymphadenectomy where information
regarding survival, morbidity, mortality, the number of resected lymph nodes in each group and detailed operative technique
were included. Four prospective, randomized trials comprising some 424 patients and one meta-analysis were identified. In
aggregate, these studies confirmed that the number of resected lymph nodes was significantly higher in the pancreaticoduodenectomy
with extended lymphadenectomy group. Morbidity and mortality rates were comparable. Postoperative diarrhea in the early months
after operation was problematic in patients undergoing extended lymphadenectomy. In none of the studies was a benefit in long-term
survival demonstrated. Standard pancreaticoduodenectomy continues to be the operation of choice for adenocarcinoma of the
head of the pancreas.
Presented at The Society for Surgery of the Alimentary Tract Postgraduate Course “Systematic Reviews of Pancreaticobiliary
Disease Customized for the Gastroenterologist and Gastrointestinal Surgeon” on May 20, 2007, Washington, D.C. 相似文献