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BACKGROUND/AIMS: 5-Fluorouracil-based chemoradiotherapy is the most widely used treatment modality in the adjuvant treatment of rectal cancer. Capecitabine represents a valuable alternative to 5-Fluorouracil in this situation. METHODOLOGY: Patients with stage II and stage III rectal adenocarcinoma, who were included in this analysis, received adjuvant chemoradiotherapy consisting of external-beam radiotherapy (50.4-54Gy) either with 5-Fluorouracil at a median dose of 300 mg/m2/day by protracted venous infusion for 5 days a week, or capecitabine at a median dose of 1650 mg/m2/day for 5 days a week after surgery. The data concerning the toxicity and the efficacy of the treatments were compared in patients treated with 5-Fluorouracil- and capecitabine-based chemoradiotherapy. RESULTS: Forty-three patients received 5-Fluorouracil, and 24 patients received capecitabine during adjuvant radiotherapy. Although there were no differences between the groups in terms of toxicity rates, distant metastasis-free survival, disease-free survival, and overall survival rates; a trend for improved loco-regional recurrence-free survival rate was observed in the capecitabine arm (p = 0.063). CONCLUSIONS: Capecitabine is at least as effective as 5-Fluorouracil in the postoperative treatment of rectal adenocarcinoma. Considering the trend for improved loco-regional recurrence-free survival rate in the capecitabine arm, it seems that the drug exerts better synergy with radiotherapy in this situation.  相似文献   
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The majority of patients with pancreatic cancer is of advanced disease. Several randomized Phase II and III trials suggest that the combination of gemcitabine and cisplatin (GemCis) response rates were higher than Gemcitabine (Gem) alone, however the trials were not enough powered to indicate a statistically significant prolongation of survival in patients with advanced pancreatic adenocarcinoma. The aim of this retrospective multicenter study is to evaluated the efficiency of Gem alone versus GemCis in patients with locally advanced and/or metastatic pancreatic adenocarcinoma .A total of 406 patients, from fourteen centers were evaluated retrospectively. All patients received Gem or GemCis as first-line treatment between September 2005 to March 2011. Primary end of this study were to evaluate the toxicity, clinical response rate, progression-free survival (PFS) and overall survival (OS) between the arms. There were 156 patients (M: 98, F: 58) in Gem arm and 250 patients (M: 175, F: 75) in the combination arm. Gemcitabin arm patients older than the combination arm ( median 63 vs 57.5, p=0.001). In patients with the combination arm had a higher dose reduction (25.2% vs 11.3%, p=0.001) and dose delay (34% vs 16.8%, p=0.001). Among patients with the combination and Gemcitabin arm gender, diabetes mellitus, performance status, cholestasis, grade, stage did not have a statistically difference (p>0.05). Clinical response rate to the combination arm was higher than the Gem arm (69.0% vs 49.7%, p=0.001). PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance (8.9 vs 6.0, p=0.08). OS was not significantly superior in the GemCis arm (12.0 vs 10.2, p>0.05). Grade III-IV hematologic and nonhematologic toxicity were higher in the combination arm. PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance. OS was not significantly superior in the GemCis arm.  相似文献   
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Background

Only limited attention has been paid to the anatomy and clinical importance of the falcine venous plexus. The aim of this study was to evaluate the falcine venous plexus anatomically using scanning electron microscopy (SEM), and to provide guidance for neurosurgical approaches.

Methods

Latex or ink was injected into the superior and inferior sagittal sinus. The falcine venous plexus lying within the connective tissue of the falx cerebri was observed by dividing the falx into thirds (anterior, middle and posterior). Further, the SEM appearance of the falcine venous plexus was evaluated.

Results

The anterior third of the falx cerebri consisted of small diameter falcine venous vessels. These vessels were localized close to either the superior or inferior sagittal sinus, and none extended as far as mid-falx cerebri levels in any of the 16 cases. They communicated with either superior or inferior sagittal sinuses, but not with both of these sinuses. In the middle third of the falx cerebri, the majority of the vessels of the falcine venous plexus had larger diameter compared to those of the anterior third. These vessels extended the length of the falx cerebri levels. They communicated with both superior and inferior sagittal sinuses. In the posterior third of the falx cerebri, the vessels of the falcine venous plexuses had the largest diameter and were located at the junction of the inferior sagittal sinus and the straight sinus. They were localized at the lower two-thirds of the falx cerebri. In all cases, the dense venous networks communicated with the inferior sagittal sinus but not with the superior sagittal sinus. The falcine venous plexus observed in the posterior third of the falx cerebri was denser than in the anterior and middle portions. The SEM revealed small vessels whose diameter ranged between 42 and 138 μm. The vessels of the falcine venous plexus in the anterior third had a mean diameter of 0.42?±?0.1 mm, in the middle third a mean diameter of 0.87?±?0.17 mm, and in the posterior third, 1.38?±?0.21 mm.

Conclusion

The falcine venous plexus is a network of venous channels that exists within the connective tissue of the falx; the sizes and patterns of communication of these structures showed regional differences. Neurosurgeons should be aware of the regional differences when making an incision or puncturing the falx during a surgical approach.  相似文献   
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