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71.
目的:探讨左炔诺酮宫内缓释系统(LNG-IUS)联合米非司酮治疗子宫腺肌病的近远期疗效及安全性。方法:将94例子宫腺肌病患者随机分为观察组(47例)和对照组(47例),观察组放置LNG-IUS,同时服用米非司酮,每月1次,疗程为6个月。对照组仅放置LNG-IUS。观察两组疗程结束后、放置LNG-IUS后1、3、5年的临床疗效及不良反应。结果:疗程结束后,观察组和对照组总有效率分别为91.5%,87.2%,差异无统计学意义(P〉0.05);随访期间,观察组的月经期、月经量、月经间期出血时间、不规则阴道流血或点滴出血的发生率均显著低于对照组,差异有统计学意义(P〈0.05);观察组和对照组不良反应的发生率分别为21.3%和25.5%,差异无统计学意义(P〉0.05)。结论:LNG-IUS联合米非司酮治疗子宫腺肌病的近远期疗效确切,可有效减少不规则阴道出血。  相似文献   
72.
C-6-based green leaf volatiles (GLVs) are signal molecules to herbivorous insects and play an important role in plant–herbivore interactions. How isomerization of GLVs affects insect’s olfactory response has been rarely tested. In laboratory and field experiments, we examined the effect of hexanol isomers on olfactory orientation of the spiraling whitefly, Aleruodicus dispersus Russell, a highly polyphagous pest. In a Y-tube oflactometer, we found that (±)-2-hexanol, 3-methyl-3-pentanol and 3,3-dimethyl-1-butanol significantly attracted female A. dispersus. The trap captures of 3,3-dimethyl-1-butanol were significantly more than that of (±)-2-hexanol and 3-methyl-3-pentanol, and its optimum concentration was 1 μ1/ml. We suggest that the anthropogenic compound 3,3-dimethyl-1-butanol can be exploited as a parakairomone (synthetic analogues of kairomone) to monitor and control adult A. dispersus.  相似文献   
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The T241M polymorphism in the X-ray cross-complementing group 3 (XRCC3) had been implicated in cancer susceptibility. The previous published data on the association between XRCC3 T241M polymorphism and cancer risk remained controversial. Hence, we performed a meta-analysis to investigate the association between cancer susceptibility and XRCC3 T241M (61,861 cases and 84,584 controls from 157 studies) polymorphism in different inheritance models. We used odds ratios with 95% confidence intervals to assess the strength of the association. Overall, significantly increased cancer risk was observed in any genetic model (dominant model: odds ration [OR] = 1.07, 95% confidence interval [CI] = 1.00–1.13; recessive model: OR = 1.15, 95% CI = 1.08–1.23; additive model: OR = 1.17, 95% CI = 1.08–1.28) when all eligible studies were pooled into the meta-analysis. In further stratified and sensitivity analyses, the elevated risk remained for subgroups of bladder cancer and breast cancer, especially in Caucasians. In addition, significantly decreased lung cancer risk was also observed. In summary, this meta-analysis suggests the participation of XRCC3 T241M in the susceptibility for bladder cancer and breast cancer, especially in Caucasians, and XRCC3 T241M polymorphism is associated with decreased lung cancer risk. Moreover, our work also points out the importance of new studies for T241M association in some cancer types, such as gastric cancer, colorectal cancer, and melanoma skin cancer, where at least some of the covariates responsible for heterogeneity could be controlled, to obtain a more conclusive understanding about the function of the XRCC3 polymorphism in cancer development.  相似文献   
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Models of stomatal conductance (gs) are based on coupling between gs and CO2 assimilation (Anet), and it is often assumed that the slope of this relationship (‘g1’) is constant across species. However, if different plant species have adapted to different access costs of water, then there will be differences in g1 among species. We hypothesized that g1 should vary among species adapted to different climates, and tested the theory and its linkage to plant hydraulics using four Eucalyptus species from different climatic origins in a common garden. Optimal stomatal theory predicts that species from sub‐humid zones have a lower marginal water cost of C gain, hence lower g1 than humid‐zone species. In agreement with the theory that g1 is related to tissue carbon costs for water supply, we found a relationship between wood density and g1 across Eucalyptus species of contrasting climatic origins. There were significant reductions in the parameter g1 during drought in humid but not sub‐humid species, with the latter group maintaining g1 in drought. There are strong differences in stomatal behaviour among related tree species in agreement with optimal stomatal theory, and these differences are consistent with the economics involved in water uptake and transport for carbon gain.  相似文献   
78.
Arabidopsis thaliana acyl‐CoA‐binding protein 2 (ACBP2) is a stress‐responsive protein that is also important in embryogenesis. Here, we assign a role for ACBP2 in abscisic acid (ABA) signalling during seed germination, seedling development and the drought response. ACBP2 was induced by ABA and drought, and transgenic Arabidopsis overexpressing ACBP2 (ACBP2‐OXs) showed increased sensitivity to ABA treatment during germination and seedling development. ACBP2‐OXs also displayed improved drought tolerance and ABA‐mediated reactive oxygen species (ROS) production in guard cells, thereby promoting stomatal closure, reducing water loss and enhancing drought tolerance. In contrast, acbp2 mutant plants showed decreased sensitivity to ABA in root development and were more sensitive to drought stress. RNA analyses revealed that ACBP2 overexpression up‐regulated the expression of Respiratory Burst Oxidase Homolog D (AtrbohD) and AtrbohF, two NAD(P)H oxidases essential for ABA‐mediated ROS production, whereas the expression of Hypersensitive to ABA1 (HAB1), an important negative regulator in ABA signalling, was down‐regulated. In addition, transgenic plants expressing ACBP2pro:GUS showed beta‐glucuronidase (GUS) staining in guard cells, confirming a role for ACBP2 at the stomata. These observations support a positive role for ACBP2 in promoting ABA signalling in germination, seedling development and the drought response.  相似文献   
79.
自2007年发现四氧化三铁纳米材料具有类似辣根过氧化物酶的催化特性以来,纳米酶研究领域迅速崛起.不同形貌、尺度和材料各异的纳米酶相继出现,同时其催化机制逐渐被认识.由于纳米酶具有催化效率高、稳定、经济和规模化制备的特点,它在医学、化工、食品、农业和环境等领域的应用研究便应运而生.纳米酶的发现,不仅推动了纳米科技的基础研究,还拓展了纳米材料的应用.本文将介绍纳米酶研究领域的最新研究进展.  相似文献   
80.
铁矿采矿迹地不同恢复年限的植被特征   总被引:2,自引:0,他引:2  
1997-2011年利用覆盖客土、覆盖客土+生态植被毯措施对北京首云铁矿尾矿库进行植被恢复,本研究调查了不同恢复年限的植被特征,并与周边自然植被进行对比分析.结果表明:恢复植被以禾本科、豆科和菊科植物为主,占植物物种总数的58%;采用客土+生态植被毯恢复的植被多度、物种丰富度和Shannon指数均接近周边未扰动植被,高于仅覆盖客土恢复的植被;客土+生态植被毯恢复植被的地上和地下部分生物量显著高于仅覆盖客土的植被,与对照差异不显著;采用客土+生态植被毯措施恢复植被的枯落物生物量第6年达到对照水平.采矿迹地植被快速重建对北京市生态涵养发展区的潜在生态功能发挥具有重要的意义,为类似采矿迹地植被重建提供可借鉴的案例.  相似文献   
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