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81.
82.
Sommerer F Vieth M Markwarth A Röhrich K Vomschloss S May A Ell C Stolte M Hengge UR Wittekind C Tannapfel A 《Oncogene》2004,23(2):554-558
Activation of the Raf/MEK/ERK (MAPK) signal transduction cascade by RAS mutations has been found in a variety of human cancers. Mutations of BRAF provide an alternative route for activation of this signalling pathway. To determine the role of mutations in BRAF and KRAS2 in the neoplastic progression of Barrett's adenocarcinoma, we analysed both genes for common mutations. After microdissection, DNA of 19 Barrett's adenocarcinomas, 56 Barrett's intraepithelial neoplasias (n=29 low-grade intraepithelial neoplasia (LGIN) and n=27 high-grade intraepithelial neoplasia (HGIN)), 30 Barrett's mucosa without neoplasia and normal squamous, as well as gastric epithelium, were analysed for BRAF and KRAS2 mutation. Activating BRAF mutations were identified in 2/19 Barrett's adenocarcinomas (11%) and in 1/27 HGIN (4%). KRAS2 mutations were found in four out of 19 (21%) Barrett's adenocarcinomas examined and in three cases of HGIN (11%). In LGIN as well as in normal gastric or oesophageal mucosa, neither BRAF nor KRAS2 mutations were detected. All lesions with KRAS2 mutations had an intact BRAF gene. The status of mismatch-repair proteins was neither related to BRAF nor KRAS2 mutations. These data indicate that RAS or BRAF mutations are detected in about 32% of all Barrett's adenocarcinomas. We conclude that the disruption of the Raf/MEK/ERK (MAPK) kinase pathway is a frequent but also early event in the development of Barrett's adenocarcinoma. 相似文献
83.
Mayer G Lingenfelser T Ell C 《Best Practice & Research: Clinical Gastroenterology》2004,18(5):799-807
Diagnostic as well as therapeutic endoscopy has a decisive role in management of early postoperative haemorrhage. Endoscopy combines easy access to the upper and lower gastrointestinal tract and application of an array of interventional tools. In near future, even the small bowel will be accessible for diagnostic and therapeutic measures due to the advent of double-balloon enteroscopy. Thus, the endoscopist increasingly replaces the surgeon for diagnosis and therapy of postsurgical bleeding. Published data on frequency and aetiology of postoperative haemorrhage are scarce and mainly casuistic. Sources of gastrointestinal bleeding associated with surgery may be: anastomotic ulcers, mucosal ischaemia, 'stress' ulcers, reflux-induced lesions, coagulopathies (e.g. in sepsis or after organ transplantation) and aortoenteric fistula after bypass surgery. The endoscopist will frequently identify the culprit lesion and guide further management of the patient (e.g. endoscopic approach, repeated surgery, interventional radiology). All accessible lesions in postoperative haemorrhage should primarily be treated by endoscopic means, except aortoenteric fistulas. There is even a place for repeated endoscopy in recurrent bleeding. In the face of lacking controlled data, the endoscopist often has to rely on his personal experience in the selection of therapeutic options. 相似文献
84.
A patient receiving intradermal injections of vaccine directed towards carcinoembryonic antigen-bearing metastases from colorectal cancer showed uptake of 18F-fluorodeoxyglucose in local draining lymph nodes during the course of treatment. This appearance should be considered as a possible false positive in patients undergoing such treatment who are being investigated with PET scans. 相似文献
85.
86.
Francis DL Visvikis D Costa DC Arulampalam TH Townsend C Luthra SK Taylor I Ell PJ 《European journal of nuclear medicine and molecular imaging》2003,30(7):988-994
Ohne Zusammenfassung 相似文献
87.
88.
Ventral hernia repair: a study of current practice 总被引:5,自引:5,他引:0
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study
was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were
gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair
was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of
repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia
size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias.
Clinical trials are required to establish the best method of repair for this common condition.
Electronic Publication 相似文献
89.
McCullough JA Evoy D Sweeney KJ Meyers C Ravi N Keeling N Byrne PJ Reynolds JV 《Irish journal of medical science》2003,172(3):132-135
Background Gastric carcinoma is a significant cause of death in Ireland. Surgery offers the best option of cure, but the five-year survival
following resection remains dismal at 10–15%. Experience from Japan and from some Western units suggest that an extended (D2)
lymphadenectomy in association with gastrectomy increases the prospect of cure, but concern about the morbidity and mortality
of this operation and lack of evidence from randomised studies has limited its acceptance.
Aims This study reports the experience of a specialist upper gastrointestinal unit with D2 gastrectomy in a four-year audit.
Methods Sixty-two resections were performed for gastric cancer. Results Nineteen patients were deemed unsuitable for the D2 procedure
and underwent a more limited lymphadenectomy (DO or D1). Forty-three patients underwent D2 resection, 12 with an oesophagogastrectomy,
22 with total gastrectomy and nine with a sub-total distal resection. Eight patients undergoing D2 resection had extended
resections, five with splenectomy and three with a distal pancreatectomy. Post-operative complications occurred in 31% of
patients. Thirty-day and 90-day mortality were zero. Median survival was 822 days in the D2 group (range 120–1,320).
Conclusions These results show that a D2 gastrectomy can be performed with a low morbidity and mortality and a median survival of greater
than two years. 相似文献
90.
Background The contribution of dysmotility to dysphagia in oesophageal cancer is unclear.
Aim To examine oesophageal motility in patients with oesophageal carcinoma and to assess the effect of chemoradiotherapy on motility.
Methods Stationary manometry and 24-hour pH-metry were performed in 12 patients with oesophageal carcinoma and one week following
completion of chemoradiotherapy using 5-fluorouracil (5-FU), cisplatin and 40Gy radiotherapy.
Results All patients had abnormal motility prior to treatment. Peristalsis was impaired in 11 patients with a mean (SD) of 25% (9)
of waves normally propagated. Eight patients had 20% or more simultaneous waves. Following chemoradiotherapy, the percentage
of waves normally propagated increased from 25% (9) to 52% (10) (p < 0.03) and normal peristalsis was restored in four patients.
The percentage of simultaneous waves decreased from 38% (11) to 21.6% (10) (p=0.129) while the percentage of dropped or increased
waves decreased from 20% (11) to 8.3% (4) (p=0.264).
Conclusions Oesophageal motility is disturbed in oesophageal cancer. Dysphagia in oesophageal cancer may be partly explained by oesophageal
dysmotility. This is improved by chemotherapy. 相似文献