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The aim of this study was to compare a combination of a locking system with self-tapping (ST-L) or self-drilling-tapping (SDT-L) screws with a combination of conventional miniplates with self-tapping (ST) and self-forming (SF) screws. A standardized osteotomy and osteosynthesis with one of the above mentioned systems was performed in 24 sheep. Callus formation was measured with the help of CT scans assisted by a navigation system. Specimens of each osteotomy gap were taken and examined histologically. The best results were observed when self-tapping screws and the Mini-Locking-System (ST-L) were applied. The slowest healing was seen in animals treated with miniplates and SF screws. After 8 weeks an increase in bone formation could be observed in the ST, SF, SDT-L systems. The results after 8 weeks were comparable with those achieved by the ST-L system after 4 weeks. The improved stability of the osteosynthesis with the ST-L system resulted in early ossification of the osteotomy gap and the smallest amount of callus formation.  相似文献   
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Background: Retained biliary stones is a common clinical problem in patients after surgery for complicated gallstone disease. When postoperative endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy are unsuccessful, several percutaneous procedures for stone removal can be applied as alternatives to relaparotomy. These procedures are performed either under fluoroscopic control or with the use of choledochoscopy, but it is also possible to combine these methods. Methods: Since 1994, we have used the percutaneous video choledochoscopic technique for the removal of difficult retained biliary stones via dilated T-tube tract in 17 patients, applying the technique of percutaneous stone extraction used in urology. While waiting for the T-tube tract to mature and after the removal of the T-tube, the dilatation of its tract was 26--30 Fr. Stone removal was carried out using a flexible video choledochoscope and a rigid renoscope under fluoroscopic control, with the aid of Dormia baskets, rigid forceps, and high-pressure irrigation. Results: We performed 23 operative procedures, and the clearance of the biliary ducts was successful in all cases. There were no major complications or deaths. Conclusion: Percutaneous video choledochoscopic--assisted removal of large retained biliary stones via the T-tube tract is a highly effective and safe procedure. Its advantages over other procedures include the ability to visualize the stones and noncalculous filling defects; it also guarantees that the stones can be removed under visual video endoscopic control. It has no problems related to tract or stone size. apd: 21 December 2000  相似文献   
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We document in vitro and in vivo effects of a novel, selective cannabinoid CB(1) receptor inverse agonist, Imidazole 24b (5-(4-chlorophenyl)-N-cyclohexyl-4-(2,4-dichlorophenyl)-1-methyl-imidazole-2-carboxamide). The in vitro binding affinity of Imidazole 24b for recombinant human and rat CB(1) receptor is 4 and 10 nM, respectively. Imidazole 24b binds to human cannabinoid CB(2) receptor with an affinity of 297 nM; in vitro, it is a receptor inverse agonist at both cannabinoid CB(1) and CB(2) receptors as it causes a further increase of forskolin-induced cAMP increase. Oral administration of Imidazole 24b blocked CP-55940-induced hypothermia, demonstrating cannabinoid CB(1) receptor antagonist efficacy in vivo. Using ex vivo autoradiography, Imidazole 24b resulted in dose-dependent increases in brain cannabinoid CB(1) receptor occupancy (RO) at 2h post-dosing in rats, indicating that approximately 50% receptor occupancy is sufficient for attenuation of receptor agonist-induced hypothermia. Imidazole 24b administered to C57Bl/6 mice and to dietary-induced obese (DIO) Sprague-Dawley rats attenuated overnight food intake with a minimal effective dose of 10 mg/kg, p.o. Administration had no effect in cannabinoid CB(1) receptor-deficient mice. DIO rats were dosed orally with vehicle, Imidazole 24b (1, 3 or 10 mg/kg), or dexfenfluramine (3 mg/kg) for 2 weeks. At 3 mg/kg, Imidazole 24b reduced cumulative food intake, leading to a non-significant decrease in weight gain. Imidazole 24b at 10 mg/kg and dexfenfluramine treatment inhibited food intake and attenuated weight gain. These findings suggest that selective cannabinoid CB(1) receptor inverse agonists such as Imidazole 24b have potential for the treatment of obesity.  相似文献   
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SUMMARY. Evidence suggests a significant difference in the incidence, presentation, and outcome of young and elderly patients with esophageal adenocarcinoma. We aimed to compare clinicopathologic and prognostic factors of young and elderly patients with esophageal adenocarcinoma at a surgical department in Europe. From 1996 to 2006, 223 patients with a resectable esophageal adenocarcinoma were analyzed and divided in three groups: (i) patients ≤50 years (n = 40); (ii) patients between 50 and 70 years (n = 131); and (iii) patients >70 years (n = 52). Clinicopathological and prognostic factors were compared between these groups. The total number of patients with esophageal adenocarcinoma increased significantly. Although the total number of patients ≤50 years increased over the years, the proportion of young patients with esophageal adenocarcinoma was rather constant. The number of patients with a pT1‐tumor was similar among all groups. Young patients had a significantly lower comorbidity and received more often a neoadjuvant radio‐chemotherapy. The 5‐year survival rate of young patients was significantly higher compared with elderly patients. In this European population, the total number of patients with adenocarcinoma of the esophagus increased dramatically in recent years, but the number of young patients remained rather constant. The better prognosis of young patients is mainly caused by less comorbidity and more frequent use of neoadjuvant therapy.  相似文献   
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