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991.
Obiageli Ezewuiro Tatyana A. Grushko Masha Kocherginsky Mohammed Habis Jean A. Hurteau Kathryn A. Mills Jessica Hunn Olufunmilayo I. Olopade Gini F. Fleming Iris L. Romero 《PloS one》2016,11(1)
There is increasing evidence that metformin, a commonly used treatment for diabetes, might have the potential to be repurposed as an economical and safe cancer therapeutic. The aim of this study was to determine whether stage III-IV or recurrent endometrial cancer patients who are using metformin during treatment with chemotherapy have improved survival. To test this we analyzed a retrospective cohort of subjects at two independent institutions who received chemotherapy for stage III-IV or recurrent endometrial cancer from 1992 to 2011. Diagnosis of diabetes, metformin use, demographics, endometrial cancer clinico-pathologic parameters, and survival duration were abstracted. The primary outcome was overall survival. The final cohort included 349 patients, 31 (8.9%) had diabetes and used metformin, 28 (8.0%) had diabetes but did not use metformin, and 291 (83.4%) did not have diabetes. The results demonstrate that the median overall survival was 45.6 months for patients with diabetes who used metformin compared to 12.5 months for patients with diabetes who did not use metformin and 28.5 months for patients without diabetes (log-rank test comparing the three groups P = 0.006). In a model adjusted for confounders, the difference in survival between the three groups remained statistically significant (P = 0.023). The improvement in survival among metformin users was not explained by better baseline health status or more aggressive use of chemotherapy. Overall, the findings in this retrospective cohort of endometrial cancer patients with stage III-IV or recurrent disease treated with chemotherapy indicate that patients with diabetes who were concurrently treated with metformin survived longer than patients with diabetes who did not use metformin. 相似文献
992.
土壤呼吸对秸秆与秸秆生物炭还田的响应及其微生物机制 总被引:3,自引:0,他引:3
土壤呼吸释放CO_2是温室气体排放的重要途径之一,减少土地利用中温室气体排放、增强土壤碳汇聚能力对于减缓全球温室效应具有重要意义。生物炭具有改善土壤理化性质、增加作物产量、调节土壤微生物性质等特性。本研究采用室外盆栽的方式,以地肤草为目标植物,研究了芦苇、水稻、互花米草三种农林秸秆及其秸秆生物炭还田对土壤的改良效应,以及对土壤呼吸的影响及其微生物机制。结果表明:秸秆及其秸秆生物炭均可改善土壤肥力,促进植物生长,且生物炭改良效果略好于秸秆直接还田。但秸秆生物炭还田的土壤呼吸显著低于秸秆直接还田,其中芦苇生物炭最低。秸秆直接还田可促进土壤β-糖苷酶、脱氢酶和活性微生物量等微生物活性指标,从而促进土壤呼吸,增加土壤CO_2的释放,而生物炭还田对土壤微生物活性无显著的促进作用,反而有一定的抑制作用,这可能是由于生物炭中易降解有机物含量很低,可降解性较低的缘故。 相似文献
993.
994.
Culetto E Baylis HA Richmond JE Jones AK Fleming JT Squire MD Lewis JA Sattelle DB 《The Journal of biological chemistry》2004,279(41):42476-42483
The anthelmintic drug levamisole causes hypercontraction of body wall muscles and lethality in nematode worms. In the nematode Caenorhabditis elegans, a genetic screen for levamisole resistance has identified 12 genes, three of which (unc-38, unc-29, and lev-1) encode nicotinic acetylcholine receptor (nAChR) subunits. Here we describe the molecular and functional characterization of another levamisole-resistant gene, unc-63, encoding a nAChR alpha subunit with a predicted amino acid sequence most similar to that of UNC-38. Like UNC-38 and UNC-29, UNC-63 is expressed in body wall muscles. In addition, UNC-63 is expressed in vulval muscles and neurons. We also show that LEV-1 is expressed in body wall muscle, thus overlapping the cellular localization of UNC-63, UNC-38, and UNC-29 and suggesting possible association in vivo. This is supported by electrophysiological studies on body wall muscle, which demonstrate that a levamisole-sensitive nAChR present at the C. elegans neuromuscular junction requires both UNC-63 and LEV-1 subunits. Thus, at least four subunits, two alpha types (UNC-38 and UNC-63) and two non-alpha types (UNC-29 and LEV-1), can contribute to levamisole-sensitive muscle nAChRs in nematodes. 相似文献
995.
目的:探讨五十营针刺循环疗法加核酪注射液穴位注射,治疗慢性支气管炎三年的临床疗效.方法:从1997年12月-2008年12月,选择支气管炎患者74例,年龄为38-80岁的中老年病人.纳入标准:符合上海市中医病症诊疗常规,同时符合内科疾病诊断标准.74例患者全部进行中医辨证分型,分为气虚痰阻和阴虚痰热两型.用五十营循环针刺法治疗,选取:中脘、关元,双侧太渊、神门、大陵、太溪、太冲、足三里、三阴交等穴,于辰巳时(上午8时-10时)用迎随补泻法治疗,留针时间为28分48秒,即一个经络循环周次.然后用核酪注射液穴位注射,每穴分别各取1mL核酪注射液,注射双侧丰隆、孔最穴.10次为1个治疗疗程,隔日1次,连续4个疗程.观察病人治疗前后咳嗽、咯痰、气急、喘息等主要症状以及舌苔、脉象的变化.结果:三年治疗及之后的随访显示,气虚痰阻型显效率为91.67%,阴虚痰热型显效率为73.07%.治疗效果显著,而复发率低.气虚痰阻型优于阴虚挟痰热型P<0.05.结论:五十营循环疗法加核酪注射液穴位注射对慢性支气管炎具有较好的临床疗效,可明显改善患者的机体免疫功能,同时具有预防和减轻疾病复发的作用. 相似文献
996.
Templates of the membrane potential profiles from lateral (LI) interneurons and motoneurons during glutamate- and N-methyl-D-aspartate (NMDA)-induced fictive locomotion showed pronounced plateau phases. In contrast, crossed caudal (CC) interneurons had a less obvious and steeper plateau region that was followed by a clear notch coinciding with the end of the lateral interneuron plateau phase. These results indicate a significant inhibitory input from LI to CC interneurons. 相似文献
997.
G E Butterfield J Gates S Fleming G A Brooks J R Sutton J T Reeves 《Journal of applied physiology》1992,72(5):1741-1748
The hypothesis that high-altitude weight loss can be prevented by increasing energy intake to meet energy requirement was tested in seven men, 23.7 +/- 4.3 (SD) yr, taken to 4,300 m for 21 days. Energy intake required to maintain body weight at sea level was found to be 3,118 +/- 300 kcal/day, as confirmed by nitrogen balance. Basal metabolic rate (BMR), determined by indirect calorimetry, increased 27% on day 2 at altitude and then decreased and reached a plateau at 17% above the sea level BMR by day 10. Energy expended during strenuous activities was 37% lower at altitude than at sea level. Fecal excretion of energy, nitrogen, total fiber, and total volatile fatty acids was not significantly affected by altitude. Energy intake at altitude was adjusted after 1 wk, on the basis of the increased BMR, to 3,452 +/- 452 kcal/day. Mean nitrogen balance at altitude was negative (-0.25 +/- 0.71 g/day) before energy intake was adjusted but rose significantly thereafter (0.20 +/- 0.71 and 0.44 +/- 0.66 g/day during weeks 2 and 3). Mean body weight decreased 2.1 +/- 1.0 kg over the 3 wk of the study, but the rate of weight loss was significantly diminished after the increase in energy intake (201 +/- 75 vs. 72 +/- 48 g/day). Individual regression lines drawn through 7-day segments of body weight showed that in four of seven subjects the slopes of body weight were not significantly different from zero after the 2nd wk. Thus weight loss ceased in four of seven men in whom increased BMR at altitude was compensated with increased energy intake.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
999.
E. A. Lyons J. E. E. Fleming G. C. Arneil A. V. Murphy E. M. Sweet Ian Donald 《BMJ (Clinical research ed.)》1972,2(5815):689-691
A technique has been developed for the ultrasonic investigation of renal disease in infants using a specially designed water-bath with a conventional ultrasonic scanner. This permits ultrasonic studies of the renal tract from the neonatal period onwards; the procedure does not distress the child and the water acts as an excellent coupling medium. 相似文献
1000.