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81.
朱建华 《彭城职业大学学报》2012,(4):5-10
烟草特有亚硝胺(TSNA)属于强致癌物,是吸烟导致癌症的重要因素.如何在成分复杂的环境烟气里吸附亚硝胺成为环境保护的难题.文章综述了近年来的研究进展,剖析了分子筛形貌对TSNA吸附的影响,讨论了液相吸附TSNA的新材料,并展望特定分子筛新材料的发展方向. 相似文献
82.
Xiu-ping Lu Bing-guang Xiao Yong-ping Li Yi-jie Gui Yu Wang Long-jiang Fan 《Journal of Zhejiang University. Science. B》2013,14(7):570-577
Diversity arrays technology (DArT) is a microarray-based marker system that achieves high throughput by reducing the complexity of the genome. A DArT chip has recently been developed for tobacco. In this study, we genotyped 267 flue-cured cultivars/landraces, including 121 Chinese accessions over five decades from widespread geographic regions in China, 103 from the Americas, and 43 other foreign cultivars, using the newly developed chip. Three hundred and thirty polymorphic DArT makers were selected and used for a phylogenetic analysis, which suggested that the 267 accessions could be classified into two subgroups, which could each be further divided into 2–4 sections. Eight elite cultivars, which account for 83% of the area of Chinese tobacco production, were all found in one subgroup. Two high-quality cultivars, HHDJY and Cuibi1, were grouped together in one section, while six other high-yield cultivars were grouped into another section. The 330 DArT marker clones were sequenced and close to 95% of them are within non-repetitive regions. Finally, the implications of this study for Chinese flue-cured tobacco breeding and production programs were discussed. 相似文献
83.
This paper assesses how use of smartphones relates to exposure to heterogeneity, political efficacy, and political engagement and suggests a new mediation model that can be applied to mobile communication. Drawing on online survey data collected during the 2012 presidential election in South Korea, this study finds that exposure to heterogeneity and political efficacy jointly mediate the impact of informational uses of smartphones on political participation. The current study also shows that informational uses of smartphones are significantly related to encounters with heterogeneity, political efficacy, and participatory behaviors. Additionally, recreational uses of smartphones were found to have a positive association with exposure to heterogeneity. However, relational uses of smartphones were not associated with democratic outcomes. The findings suggest that smartphones, by increasing the possibility of encountering diversity and subsequently enhancing political efficacy, create an additional pathway to citizen engagement in democratic processes. 相似文献
84.
85.
This paper discusses the relationship between the language use patterns of multilinguals and their media preferences and exposure. Specifically, it examines the language behavior of multilinguals in Belize where television is available in both English and Spanish. A survey of Belizean high school students conducted in both languages, asked about their sociolinguistic patterns and media preferences and exposure. The results indicate that the frequency of a particular language's use correlates with preferences for and exposure to television in that language. This relationship is more pronounced when specific cultural programming is considered. 相似文献
86.
Hillarie J. Higgins 《Education 3-13》2013,41(5):451-472
This article discusses the risks and possibilities of communicating and educating the child's emotional self in a formal classroom environment. Through designing and implementing an expressive arts curricular intervention in a Scottish primary school classroom, my research produces an example of how therapeutic notions focused upon health and wellbeing can be integrated into contemporary education. Four case studies are provided to exemplify how individual children made particular sense of emotional expression through their own lens of interactive communication with parental figures. This article argues that educators' active and ongoing awareness of boundaries, disclosure and exposure will determine the ethical nature of a child's educational experience with emotional expression. 相似文献
87.
在植物体内植物络合素(PC)可与重金属螯合,并进一步转运至液泡贮存,使细胞质的重金属浓度降低,从而达到解毒效果。PC不是基因的直接翻译产物,而是以谷胱甘肽(GSH) 为底物由植物络合素合酶催化而成。将来源于重金属超富集植物印度芥菜(Brassica juncea)的植物络合素合酶基因BjPCS1转入烟草,PCR和Northern结果表明,该基因已经整合到烟草基因组中,并在转录水平上表达。在3种重金属(200mmol/L CdCl2、400mmol/L ZnCl2、200mmo/L NiCl2)胁迫条件下,转基因烟草植株的脯氨酸含量、可溶性糖含量、丙二醛含量、相对电导率和叶绿素含量等指标均优于未转化的对照植株,表明转化BjPCS1基因提高了烟草对3种重金属的抗性,其中转基因烟草抗Cd能力最强,并且转基因烟草的T1代种子在Cd处理的情况下萌发状况明显优于对照。这些结果说明BjPCS1基因在利用基因工程改良植物抗重金属能力和净化环境污染方面,具有良好的应用前景。 相似文献
88.
Eric R. Muoz Jaclyn B. Caccese Brittany E. Wilson Kyle T. Shuler Fernando V. Santos Carolina T. Cabn John J. Jeka Dianne Langford Matthew B. Hudson 《运动与健康科学(英文)》2021,10(2):122-130
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease. 相似文献
89.
对云南支柱产业的反思 总被引:2,自引:0,他引:2
区域产业结构应保持三个时代的产业部门(兴旺部门、后备部门、衰退部门)。在云南经济高速增长20多年的背景下,如何将后备部门培植成兴旺部门,即建设新的支柱产业,是跨世纪的重大课题。本通过对烟草支柱产业建设的剖析,提出建设云南新支柱产业的道路选择;农工结合、科技支撑、制度创新。 相似文献
90.
KD4-1、Z4、KD4-2、KD4-4、H95-1等新品系优于对照品种NC89,KD4-1表现最好,KD4-3次于对照NC89,表现最差。 相似文献