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991.
992.
Although substantial progress has been made in pediatric brain tumor management, patients with brainstem tumors and high-grade gliomas, as well as patients less than 3 years of age with high-risk malignant tumors, have a poorer prognosis. The authors have been treating these patients with radiotherapy and standard carboplatin and vincristine chemotherapy. Since January 2007 the authors have been using valproate as anticonvulsant for prophylaxis. The authors performed a retrospective cohort analysis of pediatric patients with high-risk brain tumors treated with chemotherapy, radiotherapy, and valproate prophylaxis, comparing this group with a historical control. The 2007-2008 group was comprised of 22 patients, 15 with brainstem tumors (7 diffuse intrinsic pontine glioma [DIPG], 3 focal, the remaining infiltrating with a solid portion), 4 with diencephalic tumors (2 thalamic), and 3 with supratentorial high-grade tumors (1 glioblastoma, 1 recurrent grade III ependymoma, 1 with gliomatosis). There were 15 patients alive (68%) after a mean follow-up time of 19 months. Survival function comparison by log rank test was highly significant (P = .004) with a hazard ratio of 0.31 (0.14-0.70). Radiological response showed 3 complete responses (14%), 8 partial responses (36%), 5 stable diseases (23%), and 5 progresssive diseases (23%). The authors hypothesize that valproate may have potentiated the antiangiogenic effect of vincristine, diminished expression of resistance to carboplatin, and sensitized tumor cells to radiotherapy. The authors suggest that clinical trials of carboplatin and vincristine associated with oral continuous low-dose valproate are indicated for pediatric patients with high-risk brain tumor.  相似文献   
993.
Polyester fibers (PES) are the most consumed textile fibers due to their low water absorption; non-ionic character and high crystallinity. However, due to their chemical structure, the chemical interactions between polyester, finishing products, and dyes are quite challenging. We report on the use of ozone to modify the surface of polyester fibers with the goal of improving the interaction of the modified surface with finishing compounds and dyes. We used C.I. Disperse Yellow 211 to dye ozone-treated polyester fabrics and evaluated the effects of ozone treatment using FTIR-ATR, Raman spectroscopy, SEM imaging, rubbing tests, and capillarity measurements. We evaluated the dyeing performance via color analysis, and determined the dyeing kinetics. Experimental results indicate that the modification of polyester fabrics with ozone is a feasible pre-treatment that improves dyeing efficiency allowing better solidity of color and a decrease in the amount of dye required.  相似文献   
994.
Diffuse intrinsic pontine glioma is a pediatric oncologic disease with dismal prognosis and no effective treatment. Since 2007, our patients have been using valproic acid as prophylactic anticonvulsant. We have undertaken a retrospective study in order to evaluate the influence of valproate in the outcomes of children with this disease in our center. Patients were treated with weekly carboplatin and vincristine and received conformal radiotherapy, either concurrent or sequential. Event-free survival and overall survival of patients not treated with valproic acid were 6.5 and 7.8 months. Accelerated failure time model (a parametric multivariate regression test for time-to-failure data) showed a statistically significant superiority of the median event-free survival of treated patients (6.5 vs. 9.5 months in treated patients; HR 0.54–95 % CI 0.33–0.87; p < 0.05) and also of overall survival (7.8 vs. 13.4 months in treated patients; HR 0.60–95 % CI 0.37–0.98; p = 0.05).  相似文献   
995.
Applied Spatial Statistics used in conjunction with geographic information systems (GIS) provide an efficient tool for the surveillance of diseases. Here, using these tools we analyzed the spatial distribution of Hansen''s disease in an endemic area in Brazil. A sample of 808 selected from a universe of 1,293 cases was geocoded in Mossoró, Rio Grande do Norte, Brazil. Hansen''s disease cases were not distributed randomly within the neighborhoods, with higher detection rates found in more populated districts. Cluster analysis identified two areas of high risk, one with a relative risk of 5.9 (P = 0.001) and the other 6.5 (P = 0.001). A significant relationship between the geographic distribution of disease and the social economic variables indicative of poverty was observed. Our study shows that the combination of GIS and spatial analysis can identify clustering of transmissible disease, such as Hansen''s disease, pointing to areas where intervention efforts can be targeted to control disease.  相似文献   
996.
赤芝子实体中三萜化学成分的研究   总被引:10,自引:0,他引:10  
自赤芝[Ganoderma lucidum (Fr.)Karst]的二氯甲烷溶解部分分离得到一个新的三萜内酯化合物,命名为灵芝内酯(ganolactone)。根据光谱(UV,IR,1HNMR,13CNMR,MS和2DNMR)解析,确定其结构为I式。同时还从赤芝子实体中分到三个已知化合物,即灵芝醇A(ganoderiolA,II),灵芝醇B(ganoderiolB,II)和灵芝三醇(ganodermatriolIV)。  相似文献   
997.
998.
背景和目的:观察特发性肺纤维化(IPF)患者在6分钟步行试验(6MWT)结束后1min和2min时心率储备率,探讨该指标是否可以预测IPF患者的病死率.方法:对2003至2008年美国国市犹太医学研究中心的76例IPF患者进行肺功能评估和6MWT.  相似文献   
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1000.
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