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101.
PURPOSE: Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer. PATIENTS AND METHODS: Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m(2) orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8. RESULTS: Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment. CONCLUSION: The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points.  相似文献   
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BOOK REVIEWS     
A note of encouragement to those hesitant or waiting to write for our journal, together with a guide to some of the ‘props’ of the trade.  相似文献   
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BackgroundIn patients presenting with an acute coronary syndrome, left over right coronary dominance appears to be independently associated with increased long-term mortality. This could lead to decreasing numbers of patients with a left dominant coronary artery system in older age groups.MethodsWe assessed the type of coronary dominance in different age groups in postmortem angiograms that were routinely performed at autopsy between 1993 and 2007. Coronary dominance was determined by identifying the origin of the posterior descending artery and posterolateral branches on postmortem angiography. Age, gender, and cause of death were recorded from the autopsy database. The prevalence of left dominant, right dominant, and codominant systems was determined in three increasing age categories, with cutoffs based on tertiles.ResultsA total 1620 coronary angiograms were assessed; 167 were excluded because it was not possible to determine coronary dominance. The median age of all patients was 71 years; 56% were male. Of all deaths, 40% were classified as cardiac. Regarding coronary dominance, 81.2% was right, 9.1% was left, and 9.7% was codominant. Overall, a decrease in prevalence of left and codominant coronary systems was observed with increasing age in the three age cohorts (≤63years, 64–75 years, and ≥76 years) (P=.001 for overall comparison).ConclusionsIn this large autopsy cohort, the prevalence of a left dominant or codominant coronary system decreased with increasing age. These findings could relate to a slightly higher risk of mortality in case of left versus right coronary artery occlusion.  相似文献   
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Teeth adopt a variety of different morphologies, each of which is presumably optimized for performing specific functions during feeding. It is generally agreed that the enamel cap is a crucial element in controlling the mechanical behavior of mammalian teeth under load. Incisors are particularly interesting in terms of structure–function relations, as their role in feeding is that of the ‘first bite’. However, little is known how incisor cap morphology is related to tooth deformation. In the present paper we examine the mechanical behavior of mandibular central incisors in the cercopithecine primate Macaca mulatta under loads similar to those encountered during ingestion. We map three‐dimensional displacements on the labial surface of the crown as it is compressed, using electronic speckle pattern interferometry (ESPI), an optical metrology method. In addition, micro‐computed tomography is used to obtain data regarding the morphology of the enamel cap, which in the M. mulatta lower incisors exhibits missing or very little enamel on the lingual face. The results showed that although compressed along a longitudinal axis, deformation in the incisors mostly occurred in the lingual direction and orthogonal to the direction of the applied load. Both isolated, embedded teeth and teeth in the mandible showed considerable lingual deformation. Incisor deformation in the mandible was generally greater, reflecting the additional freedom of movement enabled by the supporting structures. We show that the association with adjacent teeth in the arch is significant for the behavior of the tooth under load. Finally, loading two teeth simultaneously in the mandible showed that they work as one functional unit. We suggest that these results demonstrate the importance of enamel cap morphology in directing deformation behavior; an ability stemming from the stiffness of the enamel cap overlying the more pliable dentin.  相似文献   
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