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排序方式: 共有194条查询结果,搜索用时 46 毫秒
41.
Elas M Bell R Hleihel D Barth ED McFaul C Haney CR Bielanska J Pustelny K Ahn KH Pelizzari CA Kocherginsky M Halpern HJ 《International journal of radiation oncology, biology, physics》2008,71(2):947-549
PURPOSE: Tumor hypoxia has long been known to produce resistance to radiation. In this study, electron paramagnetic resonance (EPR) oxygen imaging was investigated for its power to predict the success of tumor control according to tumor oxygenation level and radiation dose. METHODS AND MATERIALS: A total of 34 EPR oxygen images were obtained from the legs of C3H mice bearing 0.5-cm(3) FSa fibrosarcomas under both normal (air breathing) and clamped tumor conditions. Under the same conditions as those during which the images were obtained, the tumors were irradiated to a variety of doses near the FSa dose at which 50% of tumors were cured. Tumor tissue was distinguished from normal tissue using co-registration of the EPR oxygen images with spin-echo magnetic resonance imaging of the tumor and/or stereotactic localization. The tumor voxel statistics in the EPR oxygen image included the mean and median partial pressure of oxygen and the fraction of tumor voxels below the specified partial pressure of oxygen values of 3, 6, and 10 mm Hg. Bivariate logistic regression analysis using the radiation dose and each of the EPR oxygen image statistics to determine which best separated treatment failure from success. RESULTS: The measurements of the dose at which 50% of tumors were cured were similar to those found in published data for this syngeneic tumor. Bivariate analysis of 34 tumors demonstrated that tumor cure correlated with dose (p = 0.004) and with a <10 mm Hg hypoxic fraction (p = 0.023). CONCLUSION: Our results have shown that, together, radiation dose and EPR image hypoxic fraction separate the population of FSa fibrosarcomas that are cured from those that fail, thus predicting curability. 相似文献
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目的临床和人群研究提示,脱氢表雄酮和它的硫酸盐在抗动脉粥样硬化和冠心病中起保护作用。然而,这种作用的机制仍不清楚。最近报道,硫酸脱氢表雄酮通过增加一氧化氮的生成来延缓动脉粥样硬化的形成。方法24岁的男性受试者(年龄65.4±0.7岁;范围58.2~67.6岁)经盲法安慰剂对照研究,使用脱氢表雄酮(每天50 mg睡前口服)或安慰剂2个月。2个月前和2个月后评价血小板环一磷酸鸟苷(cGMP)浓度(作为一氧化氮产生的标记)和血清中硫酸脱氢表雄酮钠、脱氢表雄酮、胰岛素样生长因子1、胰岛素、葡萄糖、雌二醇、睾酮、纤溶酶原激活物抑制剂1抗原、高半胱… 相似文献
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Masha Livhits Cheryl Mercado Irina Yermilov Janak A. Parikh Erik Dutson Amir Mehran Clifford Y. Ko Melinda Maggard Gibbons 《Surgery for obesity and related diseases》2009,5(6):713-721
BackgroundPreoperative weight loss before bariatric surgery has been proposed as a predictive factor for improved patient compliance and the degree of excess weight loss achieved after surgery. In the present study, we sought to determine the effect of preoperative weight loss on postoperative outcomes.MethodsA search of MEDLINE was completed to identify the patient factors associated with weight loss after bariatric surgery. Of the 909 screened reports, 15 had reported on preoperative weight loss and the degree of postoperative weight loss achieved. A meta-analysis was performed that compared the postoperative weight loss and perioperative outcomes in patients who had lost weight preoperatively compared to those who had not.ResultsOf the 15 articles (n = 3404 patients) identified, 5 found a positive effect of preoperative weight loss on postoperative weight loss, 2 found a positive short-term effect that was not sustained long term, 5 did not find an effect difference, and 1 found a negative effect. A meta-analysis revealed a significant increase in the 1-year postoperative weight loss (mean difference of 5% EWL, 95% confidence interval 2.68–7.32) for patients who had lost weight preoperatively. A meta-analysis of other outcomes revealed a decreased operative time for patients who had lost weight preoperatively (mean difference 23.3 minutes, 95% confidence interval 13.8–32.8).ConclusionPreoperative weight loss before bariatric surgery appears to be associated with greater weight loss postoperatively and might help to identify patients who would have better compliance after surgery. 相似文献
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Somi MF Butler JR Vahid F Njau JD Kachur SP Abdulla S 《Tropical medicine & international health : TM & IH》2007,12(10):1139-1147
OBJECTIVE: To determine the economic burden of malaria in a rural Tanzanian setting and identify any differences by socioeconomic status and season. METHODS: Interviews of 557 households in south eastern Tanzania between May and December 2004, on consumption and malaria-related costs. RESULTS: Malaria-related expenses were significantly higher in the dry, non-malarious season than in the rainy season. Households sought treatment more frequently and from more expensive service providers in the dry season, when they have more money. Malaria expenses did not vary significantly across socioeconomic status quintiles, but poorer households spent a higher proportion of their consumption in both seasons. CONCLUSION: Poorer households bear a greater economic burden from malaria relative to their consumption than better-off households. Households are particularly vulnerable to malaria in the rainy season, when malaria prevalence is highest but liquidity is lower. Alternative strategies to assist households to cope with seasonal liquidity issues, including insurance, should be investigated. 相似文献
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Hussein O Grosovski M Lasri E Svalb S Ravid U Assy N 《World journal of gastroenterology : WJG》2007,13(3):361-368
AIM: To evaluate the effects of different types of dietary fats on the hepatic lipid content and oxidative stress parameters in rat liver with experimental non-alcoholic fatty liver disease (NAFLD). METHODS: A total of 32 Sprague-Dawley rats were randomly divided into five groups. The rats in the control group (n = 8) were on chow diet (Group 1), rats (n = 6) on methionine choline-deficient diet (MCDD) (Group 2), rats (n = 6) on MCDD enriched with olive oil (Group 3), rats (n = 6) on MCDD with fish oil (Group 4) and rats (n = 6) on MCDD with butter fat (Group 5). After 2 mo, blood and liver sections were examined for lipids composition and oxidative stress parameters.
RESULTS: The liver weight/rat weight ratio increased in all treatment groups as compared with the control group. Severe fatty liver was seen in MCDD + fish oil and in MCDD + butter fat groups, but not in MCDD and MCDD + olive oil groups. The increase in hepatic triglycerides (TG) levels was blunted by 30% in MCDD + olive oil group (0.59 ±0.09) compared with MCDD group (0.85 ±0.04, P 〈 0.004), by 37% compared with MCDD + fish oil group (0.95 ±0.07, P 〈 0.001), and by 33% compared with MCDD + butter group (0.09 ±0.1, P 〈 0.01). The increase in serum TG was lowered by 10% in MCDD + olive oil group (0.9 ±0.07) compared with MCDD group (1.05 ±0.06). Hepatic cholesterol increased by 15-fold in MCDD group [(0.08 ±0.02, this increment was blunted by 21% in MCDD + fish oil group (0.09 ±0.02)]. In comparison with the control group, ratio of long-chain polyunsaturated fatty acids omega-6/omega-3 increased in MCDD + olive oil, MCDD + fish oil and MCDD + butter fat groups by 345-, 30- and 397-fold, respectively. In comparison to MCDD group (1.58 ±0.08), hepatic MDA contents in MCDD + olive oil (3.3 ±0.6), MCDD + fish oil (3.0 ±0.4), and MCDD + butter group (2.9 ±0.36) were increased by 108%, 91% and 87%, respecti 相似文献
RESULTS: The liver weight/rat weight ratio increased in all treatment groups as compared with the control group. Severe fatty liver was seen in MCDD + fish oil and in MCDD + butter fat groups, but not in MCDD and MCDD + olive oil groups. The increase in hepatic triglycerides (TG) levels was blunted by 30% in MCDD + olive oil group (0.59 ±0.09) compared with MCDD group (0.85 ±0.04, P 〈 0.004), by 37% compared with MCDD + fish oil group (0.95 ±0.07, P 〈 0.001), and by 33% compared with MCDD + butter group (0.09 ±0.1, P 〈 0.01). The increase in serum TG was lowered by 10% in MCDD + olive oil group (0.9 ±0.07) compared with MCDD group (1.05 ±0.06). Hepatic cholesterol increased by 15-fold in MCDD group [(0.08 ±0.02, this increment was blunted by 21% in MCDD + fish oil group (0.09 ±0.02)]. In comparison with the control group, ratio of long-chain polyunsaturated fatty acids omega-6/omega-3 increased in MCDD + olive oil, MCDD + fish oil and MCDD + butter fat groups by 345-, 30- and 397-fold, respectively. In comparison to MCDD group (1.58 ±0.08), hepatic MDA contents in MCDD + olive oil (3.3 ±0.6), MCDD + fish oil (3.0 ±0.4), and MCDD + butter group (2.9 ±0.36) were increased by 108%, 91% and 87%, respecti 相似文献