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971.
972.
Spinelli A Schumacher G Pascher A Lopez-Hanninen E Al-Abadi H Benckert C Sauer IM Pratschke J Neumann UP Jonas S Langrehr JM Neuhaus P 《World journal of gastroenterology : WJG》2006,12(14):2293-2296
Xanthogranulomatous cholecystitis (XGC) is a destructive inflammatory disease of the gallbladder, rarely involving adjacent organs and mimicking an advanced gallbladder carcinoma. The diagnosis is usually possible only after pathological examination. A 46 year-old woman was referred to our center for suspected gallbladder cancer involving the liver hilum, right liver lobe, right colonic flexure, and duodenum. Brushing cytology obtained by endoscopic retrograde cholangiography (ERC) showed high-grade dysplasia. The patient underwent an en-bloc resection of the mass, consisting of right lobectomy, right hemicolectomy, and a partial duodenal resection. Pathological examination unexpectedly revealed an XGC. Only six cases of extended surgical resections for XGC with direct involvement of adjacent organs have been reported so far. In these cases, given the possible coexistence of XGC with carcinoma, malignancy cannot be excluded, even after cytology and intraoperative frozen section investigation. In conclusion, due to the poor prognosis of gallbladder carcinoma on one side and possible complications deriving from highly aggressive inflammatory invasion of surrounding organs on the other side, it seems these cases should be treated as malignant tumors until proven otherwise. Clinicians should include XGC among the possible differential diagnoses of masses in liver hilum. 相似文献
973.
Lichtenberg A Cebotari S Tudorache I Sturz G Winterhalter M Hilfiker A Haverich A 《The Journal of heart valve disease》2006,15(2):287-93; discussion 293-4
BACKGROUND AND AIM OF THE STUDY: The generation of a functional, non-immunogenic, non-thrombogenic construct based on autologous cells seeded onto an acellular extracellular matrix is the major goal in heart valve tissue engineering. The study aim was to identify culturing conditions required to achieve a stable endothelial cell (EC) layer under physiological flow conditions, a prerequisite for the requested characteristics. METHODS: Eleven detergent-decellularized ovine pulmonary valves (PVs) were statically reseeded in special bioreactors with ovine venous ECs (1.2x10(7) cells per valve). The dynamic culture was started with 0.1 l/min in eight bioreactors. In four bioreactors the initial flow rate was slow, and increased by 0.1 l/min twice each day until maximal flow was 0.5 l/min and pulsation rate (PR) was 20 beats/min; in four other bioreactors the flow was increased by 0.7 l/min/day and reached 2.0 l/min with a PR of 50 beats/min. The mean system pressure was maintained at 25 +/- 5 mmHg during the whole dynamic cultivation in both groups. Three statically reseeded valves served as baseline. After achieving maximal appointed flow, the valves were investigated morphologically (hematoxylin and eosin staining, electron microscopy, von Willebrand factor, endothelial nitric oxide synthase immunostaining) and for metabolic activity (MTS assay). RESULTS: After reseeding, the endothelium appeared on the luminal surface of the PV as a non-confluent monolayer. Moderate pulsatile circulation induced complete confluence of EC monolayers on both cusp sides and the pulmonary wall. A high flow rate led to a partial loss of cells on the wall surface with large defects, and to complete cell wash-off from cusps. Cusp and wall metabolic activity was significantly higher after culture under moderate flow (p < 0.001) than in other groups, and was absent from cusps in high-flow bioreactors. CONCLUSION: Moderate pulsatile flow with small increments stimulates EC proliferation on the ovine decellularized valve scaffold. A rapid increase in bioreactor flow to physiological levels leads to significant damage of the reseeded endothelium and complete loss of cusp cellularity. This effect may be responsible for the in-vivo failure of static reseeded tissue-engineered valves exposed to physiological hemodynamic forces. 相似文献
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975.
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977.
DeFrain M Strickman NE Ljubic BJ Dougherty KG Gregoric ID 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2006,33(2):241-245
Endovascular aneurysm repair has considerable potential advantages over the surgical approach as a treatment for thoracic aortic rupture, in part because open surgical repair of ruptured thoracic aortic aneurysms is associated with high mortality and morbidity rates. We describe the successful endovascular deployment of stent-grafts to repair a contained rupture of a descending thoracic aortic aneurysm in an 86-year-old man whose comorbidities prohibited surgery. Two months after the procedure, magnetic resonance angiography showed a patent stent-graft, a patent left subclavian artery, and complete exclusion of the aneurysm. 相似文献
978.
979.
980.
Modlin IM Latich I Zikusoka M Kidd M Eick G Chan AK 《Journal of clinical gastroenterology》2006,40(7):572-582
Carcinoid tumors are rare, often insidious neoplasms arising from neuroendocrine cells. The majority arise in the gastrointestinal system, and are often incidentally found during investigation, although some may present as an emergency bleed or perforation. The prosaic symptoms of flushing, diarrhea, and sweating are often overlooked; thus, the diagnosis is usually much delayed and the tumor is advanced at presentation. This diagnostic delay renders effective management difficult and adversely affects outcome. This overview provides a current assessment of the evolution of the diagnostic techniques available to establish an accurate biochemical (5-hydroxyindole-3-acetic acid and chromogranin A) and topographic diagnosis (octreoscan, radio-labeled metaidobenzylguanidine, computerized tomography, magnetic resonance imaging, positron emission tomography, enteroclysis, endoscopic ultrasound, enteroscopy, capsule endoscopy, and angiography) of carcinoid tumors. The utility and shortcomings of the respective modalities available are evaluated. Although considerable advances have been made in establishing the diagnosis of carcinoid tumors and in defining the topography of metastatic disease, the major limitation is the inability to establish an early and timely diagnosis before the advent of metastatic disease. 相似文献