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11.
Mi YY  Zhu LJ  Wu S  Feng NH 《Genes & nutrition》2011,6(4):397-402
Encoding ribonuclease L (RNASEL) is a ubiquitously expressed latent endoribonuclease involved in the mediation of antiviral and pro-apoptotic activities of the interferon-inducible 2-5A system. Although the relationship between RNASEL gene polymorphisms and prostate cancer (PCa) risk has been widely reported, results were somewhat controversial and underpowered. Now, we performed an update analysis of 14 publications evaluating the association between RNASEL R462Q and D541E polymorphisms and PCa risk. We conducted a literature search of PubMed database to identify all eligible articles that examined the association of RNASEL R462Q and D541E polymorphisms with PCa. Odds ratios (OR) with 95% confidence intervals (CI) were estimated to assess these association. R462Q showed a significantly elevated effect on Africans (QQ vs. RR: OR = 2.50, 95% CI = 1.28–4.87, Pheterogeneity = 0.231). In addition, PCa men who contain 462Q genotype had a higher Gleason score ≥ 7 (OR = 1.16, 95% CI = 1.05–1.28, Pheterogeneity = 0.906). On the other hand, D541E was associated with increased total PCa. In the stratified analysis by race, there was also significantly increased PCa in Africans and Caucasians, as well as in sporadic PCa studies (OR = 1.09, 95% CI = 1.04–1.15, Pheterogeneity = 0.078). Our update analysis showed evidence that RNASEL R462Q and D541E polymorphisms were associated with PCa risk. Still more well-designed studies should be performed to clarify the role of these two polymorphisms in the development of PCa.  相似文献   
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本文研究了分布在细叶益母草(Leonurus sibiricus)叶表面三种腺毛的发育过程,在此基础上,对2-细胞头状腺毛、4-细胞头状腺毛和8-细胞盾状腺毛的多样性特征进行了讨论。  相似文献   
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利用扫描电子显微镜对跳甲属Altica北京有分布的7个种的卵的形态结构进行观察和对比研究。结果表明7种卵在卵的大小、卵壳表面纹饰的形状、纹饰突起的程度、孔洞的多少等均存在明显差异。据此探讨了卵的表面形态结构在分类和系统发育中的作用,同时还探讨卵的形态结构与昆虫生境的相关性。  相似文献   
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Butanol has recently gained increasing interest due to escalating prices in petroleum fuels and concerns on the energy crisis. However, the butanol production cost with conventional acetone–butanol–ethanol fermentation by Clostridium spp. was higher than that of petrochemical processes due to the low butanol titer, yield, and productivity in bioprocesses. In particular, a low butanol titer usually leads to an extremely high recovery cost. Conventional biobutanol recovery by distillation is an energy-intensive process, which has largely restricted the economic production of biobutanol. This article thus reviews the latest studies on butanol recovery techniques including gas stripping, liquid–liquid extraction, adsorption, and membrane-based techniques, which can be used for in situ recovery of inhibitory products to enhance butanol production. The productivity of the fermentation system is improved efficiently using the in situ recovery technology; however, the recovered butanol titer remains low due to the limitations from each one of these recovery technologies, especially when the feed butanol concentration is lower than 1 % (w/v). Therefore, several innovative multi-stage hybrid processes have been proposed and are discussed in this review. These hybrid processes including two-stage gas stripping and multi-stage pervaporation have high butanol selectivity, considerably higher energy and production efficiency, and should outperform the conventional processes using single separation step or method. The development of these new integrated processes will give a momentum for the sustainable production of industrial biobutanol.  相似文献   
17.
非损伤微测技术在植物生理学研究中的应用及进展   总被引:3,自引:0,他引:3  
非损伤微测技术(NMT)是一种选择性微电极技术,可以在不损伤活体样品的情况下获得进出样品的各种离子或分子浓度、流速及其三维运动方向的信息。该技术具有非损伤性、长时间、多电极、高分辨率、高灵敏度、多角度测量等优点,可获得其他技术难以测到的生理特征和生命活动规律,从而在理论研究和应用领域产生实质性的突破。本文综述了近年来NMT在植物营养调控、抗病性、抗盐碱、抗旱、抗冷、抗重金属毒害等方面的应用及其进展,并展望了NMT在植物生理学研究中的应用前景。  相似文献   
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We conducted a meta-analysis of case–control studies to determine whether SELP genetic polymorphisms contribute to the pathogenesis of coronary heart disease (CHD) and myocardial infarction (MI). A range of electronic databases were searched: MEDLINE (1966–2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980–2013), CINAHL (1982–2013), Web of Science (1945–2013) and the Chinese biomedical database (1982–2013) without language restrictions. Meta-analysis was performed with the use of the STATA statistical software. Nine case–control studies with a total of 3,154 CHD patients, 1,608 MI patients and 17,304 healthy controls were involved in this meta-analysis. Six common polymorphisms in the SELE gene were assessed, including ?1969G/A (rs1800805 G > A), ?1817T/C (rs1800808 T > C), ?2123C/G (rs1800807 C > G), Thr715Pro (rs6136 A > C), Leu599Val (rs6133 G > T), and Ser290Asn (rs6131 C > T). Our findings illustrated significantly positive associations of SELE genetic polymorphisms with the development of CHD and MI. The results of subgroup analysis by SNP type indicated that ?1969G/A, ?1817T/C, ?2123C/G, Thr715Pro and Ser290Asn in the SELP gene might be strongly correlated with CHD and MI risk, but no similar results were found in SELP Leu599Val polymorphism. In the subgroup analysis by ethnicity, our results indicated significant relationships between SELE genetic polymorphisms and the pathogenesis of CHD and MI among Asians and Caucasians. However, we observed no significant associations between SELP genetic polymorphisms and the risk of CHD and MI among Africans. Our findings provide empirical evidence that SELE genetic polymorphisms may contribute to the pathogenesis of CHD and MI, especially among Asians and Caucasians. Thus, SELP genetic polymorphisms could be potential and practical biomarkers for early diagnosis of CHD and MI.  相似文献   
19.
烟草炭疽病拮抗生防菌的筛选   总被引:6,自引:0,他引:6  
本文应用荧光假单胞杆菌的16S-23S ribosomal RNA序列以及部分抗菌素合成基因序列的PCR鉴定引物,对从烟草根际分离到的400份细菌进行了鉴定,结果获得了21份含Prn(硝吡咯菌素)合成酶基因的荧光假单胞杆菌和1份含有DAPG(2,4-二乙酰基藤黄酚)合成酶基因以及PCA(Phenazine-1-carboxylic acid,吩嗪-1-羧酸)的荧光假单胞杆菌.室内实验结果表日月,含DAPG和PCA的荧光假单胞杆菌对烟草炭疽病具有明显拮抗作用.  相似文献   
20.
经济快速增长区城市用地空间扩展对生态安全的影响   总被引:5,自引:0,他引:5  
张健  高中贵  濮励杰  彭补拙 《生态学报》2008,28(6):2799-2799~2810
目前我国正处于经济快速发展、城市化进程加快阶段,承受着生态环境恶化的巨大压力,大多数城市已为环境污染、空间拥挤、绿化率低、秩序混乱等严重的城市问题所困扰.昆山市作为我国经济发展最为活跃的地区之一,其城市化过程与生态环境安全之间的矛盾更为突出.在总结国内外生态安全和城市生态研究的基础上,分析城市用地扩展对城市生态安全产生的影响.昆山市城市用地空间扩张经历了缓慢发展期(1949~1977年)、老城区改造期(1977~1985年)、新区开发期(1985~1999年)和快速扩展期(1999年至今)4个阶段,针对城市土地利用变化特征及其城市土地利用存在的问题,对昆山市城市用地空间扩展进程和模式及扩展的主要特征方面进行剖析.从城市废水、废气和固废排放量几个方面分析了昆山城市用地空间扩展过程中生态环境变化情况,指出高速工业化、城市化过程,快速增长的经济可能威胁到昆山城市的生态安全.同时建立城市生态安全评价模式,构建城市生态安全评价的指标体系,探讨城市生态安全评价的方法,评价了昆山市1985~2004年的城市生态安全,最后对昆山市未来城市生态安全进行预警.为维护昆山市的生态安全,实现可持续发展提供科学依据.  相似文献   
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