959 resultados para vein occlusion


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background. There is conflicting evidence on the efficacy of regional adjuvant chemotherapy, via portal-vein infusion (PVI), after resection of colorectal cancer. We undertook a randomised controlled multicentre trial to investigate the efficacy of PVI (500 mg/m2 fluorouracil plus 5000 IU heparin daily for 7 days). Methods. 1235 of about 1500 potentially eligible patients were randomly assigned surgery plus PVI or surgery alone (control). The patients were followed up for a median of 63 months, with yearly screening for recurrent disease. The primary endpoint was survival; analyses were by intention to treat. Findings. 619 patients in the control group and 616 in the PVI group met eligibility criteria. 164 (26%) control-group patients and 173 (28%) PVI-group patients died. 5-year survival did not differ significantly between the groups (73 vs 72%; 95% CI for difference -6 to 4). The control and PVI groups were also similar in terms of disease-free survival at 5 years (67 vs 65%) and the number of patients with liver metastases (79 vs 77%). Interpretation. PVI of fluorouracil, at a dose of 500 mg/m2 for 7 days, cannot be recommended as the sole adjuvant treatment for high-risk colorectal cancer after complete surgical excision. However, these results cannot eliminate a small benefit when PVI is used at a higher dosage or in combination with mitomycin.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study investigates face recognition with partial occlusion, illumination variation and their combination, assuming no prior information about the mismatch, and limited training data for each person. The authors extend their previous posterior union model (PUM) to give a new method capable of dealing with all these problems. PUM is an approach for selecting the optimal local image features for recognition to improve robustness to partial occlusion. The extension is in two stages. First, authors extend PUM from a probability-based formulation to a similarity-based formulation, so that it operates with as little as one single training sample to offer robustness to partial occlusion. Second, they extend this new formulation to make it robust to illumination variation, and to combined illumination variation and partial occlusion, by a novel combination of multicondition relighting and optimal feature selection. To evaluate the new methods, a number of databases with various simulated and realistic occlusion/illumination mismatches have been used. The results have demonstrated the improved robustness of the new methods.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Deep vein thrombosis (DVT) presents a significant risk for women requiring Caesarean section.
Venous thromboembolism (VTE) remains the leading direct cause of maternal death in the
UK and is the second most common cause of maternal death worldwide, accounting for 11%
of maternal deaths (RCOG 2009). This article uses a reflective cycle to explore the role of the
preoperative practitioner in the prevention of DVT for women undergoing elective Caesarean
section.