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61.
Li QY Niu HB Yin J Shao HB Niu JS Ren JP Li YC Wang X 《Journal of Zhejiang University. Science. B》2010,11(11):862-870
A transgenic barley line (LSY-11-1-1) with overexpressed Phalaris coerulescens thioredoxin gene (PTrx) was employed to measure the growth, protein oxidation, cell viability, and antioxidase activity in barley roots during germination
on the presence of 2 mmol/L AlCl3 on filter paper. The results show that (1) compared with the non-transgenic barley, LSY-11-1-1 had enhanced root growth,
although both were seriously inhibited after AlCl3 treatment; (2) the degree of protein oxidation and loss of cell viability in roots of LSY-11-1-1 were much less than those
in roots of non-transgenic barley, as reflected by lower contents of protein carbonyl and Evans blue uptakes in LSY-11-1-1;
(3) activities of catalase (CAT), glutathione peroxidase (GPX), ascorbate peroxidase (APX), and glutathione reductase (GR)
in LSY-11-1-1 root tips were generally higher than those in non-transgenic barley root tips, although these antioxidase activities
gave a rise to different degrees in both LSY-11-1-1 and non-transgenic barley under aluminum stress. These results indicate
that overexpressing PTrx could efficiently protect barley roots from oxidative injury by increasing antioxidase activity, thereby quenching ROS caused
by AlCl3 during germination. These properties raise the possibility that transgenic barley with overexpressed PTrx may be used to reduce the aluminum toxicity in acid soils. 相似文献
62.
63.
通过了解压力应对理论的发展和我国大学生压力应对研究的现状,认为当前我国大学生压力应对方面的研究虽然取得了一定成果,但在研究方法多维度、研究手段科学性、实践应用广泛性上存在不足等问题。因此,提出规范压力应对的科学研究、构建压力应对实践体系是增强大学生压力应对能力的关键。 相似文献
64.
从理论方面,对国内外主应力轴旋转情况下土的各向异性研究进行了对比和总结,并提出了一些研究建议。指出在理论方面,应当对屈服面方程采用应力分量表示的模型在三维空间里进行屈服面性状的描述,同时考虑不同加载方向下屈服面的变化特性以及旋转硬化的问题,并应开展对加载方向变化时土体屈服面变化特性的实验研究及理论验证。 相似文献
65.
How Moroccan mothers and fathers view child development and their role in their children's education
Gail L. Zellman Michal Perlman Rita Karam 《International Journal of Early Years Education》2014,22(2):197-209
Despite the documented importance of parental engagement in early learning, little is known about how parents in the Middle East and North Africa understand child development. To inform the literature, a small-scale study involving four focus groups was conducted with parents of children aged six years and under living in Casablanca. The purpose of this study was to explore parents' understanding of and support for their children's early development. Results reveal that parents see a vital role for themselves in their children's upbringing as supporters and nurturers, but little role as teachers. Across different education and income levels, parents in this small-scale qualitative study believe that children's experiences in their first years of life do not affect their longer-term intellectual development or school success and see little value in early intellectual stimulation or formal preschool education. Our results suggest that parents need to understand their role as their child's first educators. Also, it is essential that parents are taught how to promote their children's early cognitive development without undermining their nurturing roles. 相似文献
66.
Farhana Zahir Shameem J Rizvi Soghra K Haq Rizwan H Khan 《Indian journal of clinical biochemistry : IJCB》2006,21(2):149-152
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose
mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the
effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male
albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were
tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation,
nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing
methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was
a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent
reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more
specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion
that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help
combat the risk of developing such disorders in ensuing years. 相似文献
67.
68.
文章在阐述组织承诺与压力管理的概念解析和关系认识基础上,同时基于对组织承诺与压力管理的问题进行诊断,从组织层面提出了两者的关系优化路径。 相似文献
69.
N. Unni C. Sumithra R. Lakshman Lakshmi N. Leela Menon K. N. Subhakumari V. S. Sheejamol 《Indian journal of clinical biochemistry : IJCB》2015,30(2):161-166
PCOS is a heterogeneous endocrine disorder with diverse clinical presentation. Oxidative stress plays a key role in the pathophysiology of this disease. Serumhigh sensitive C-reactive protein (hsCRP), a marker of chronic low grade inflammation, is indicative of future development of cardiovascular disease. Our aim is to evaluate the oxidant status and hsCRP levels in PCOS. The study involved 61 cases and 61 controls in the age group of 18–40 years diagnosed with PCOS. Erythrocyte malondialdehyde (MDA), superoxide dismutase (SOD), serum hsCRP, gonadotrophins, thyroid stimulating hormone, prolactin, glycemic status and lipid profile were estimated. Erythrocyte MDA (p < 0.001), SOD (p = 0.007) and serum hsCRP (p < 0.001) were significantly elevated in PCOS patients than controls. Oxidative stress is present in women with PCOS along with elevated hsCRP. 相似文献
70.
对新形势下体育院校图书馆事业深入发展的思考--兼论2003年以来教育部对体育院校图书馆的评估 总被引:4,自引:0,他引:4
从体育院校图书馆评估的基本内容和重点、体育院校图书馆发展现状与评估指标的列比分析、体育院校图书馆今后发展的重点、体育院校图书馆深入发展的对策几方面探讨了图书馆评估及体育院校图书馆事业的深入发展。 相似文献