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161.
Liu GF Zhou HK Hu H Zhu ZH Hayat Y Xu HM Yang J 《Journal of Zhejiang University. Science. B》2007,8(12):860-866
Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five component traits, including stalk diameter (SD), stalk length (SL), stalk number (SN), stalk weight (SW), and brix scale (BS) of sugarcane. Phenotypic data of all the six traits were analyzed by mixed linear model and their phenotype variances were portioned into additive (A),dominance (D), additive×environment interaction (AE) and dominance×environment interaction (DE) effects, and the correlations of A, D, AE and DE effects between BW and its components were estimated. Conditional analysis was employed to investigate the contribution of the components traits to the variances of A, D, AE and DE effects of BW. It was observed that the heritabilities of BW were significantly attributed to A, D and DE by 23.9%, 30.9% and 28.5%, respectively. The variance of A effect for BW was significantly affected by SL, SN and BS by 25.3%, 93.7% and 17.4%, respectively. The variances of D and DE effects for BW were also significantly influenced by all the five components by 5.1%~85.5%. These determinants might be helpful in sugarcane breeding and provide valuable information for multiple-trait improvement of BW. 相似文献
162.
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/(m^2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress. 相似文献
163.
Novel distribution pattern of fibrinolytic components in rabbit tissues extract: a preliminary study
Lu XG Wu XG Xu XH Gong XB Zhou X Xu GB Zhu L Zhao XY 《Journal of Zhejiang University. Science. B》2007,8(8):570-574
Objective: The purpose of this work was to investigate the distribution pattern of fibrinolytic factors and their inhibitors in rabbit tissues. Methods: The components of the fibrinolytic system in extracts from a variety of rabbit tissues, including tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI), were determined by colorimetric assay. Results: The tissue extracts in renal, small intestine, lung, brain and spleen demonstrated strong fibrinolytic function, in which high activity of tPA, Plg and Pl was manifested; whereas in skeletal muscle, tongue and stomach, higher activity of PAI-1 and α2PI showed obviously. Also excellent linear correlations were found between levels of tPA and PAI-1, Pl and α2PI, Plg and Pl. In related tissues, renal cortex and renal marrow showed distinctly higher activity of tPA and lower activity of PAI-1, with the levels of Plg and Pl in renal cortex being higher than those in renal marrow, where the α2PI level was higher than that in renal cortex. Similarly, the levels of tPA, Plg and Pl in small intestine were higher than those in large intestine, but with respect to PAI-1 and α2PI, the matter was reverse. In addition, the fibrinolytic activity in muscle tissue was lower, however, the levels of tPA, Plg, and Pl in cardiac muscle were obviously higher than those in skeletal muscles, and the levels of PAI-1 and α2PI were significantly lower than those in skeletal muscle. Conclusion: Our data demonstrate that a remarkable difference of the fibrinolytic patterns exists in rabbit tissues, which has probable profound significance in understanding the relationship between the function of haemostasis or thrombosis and the physiologic function in tissues. 相似文献
164.
Relationship between hyperuricemia and metabolic syndrome 总被引:6,自引:0,他引:6
Chen LY Zhu WH Chen ZW Dai HL Ren JJ Chen JH Chen LQ Fang LZ 《Journal of Zhejiang University. Science. B》2007,8(8):593-598
Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome. 相似文献
165.
[目的 /意义]开放科学环境下,探究预印本平台的数据开放共享政策有助于保障科研利益相关者的数据质量,推动研究数据更加开放、共享、安全与透明。[方法 /过程]基于研究团队跟踪的125个预印本平台中共63份数据开放共享政策文本,利用网络调查与文本分析的方法进行内容挖掘与特点剖析。[结果 /结论 ]通过分析得出预印本平台的数据开放共享政策在数据创建、数据存储、数据发布、数据访问、数据重用5个阶段的主要特征,为更多预印本平台在未来制定完备的数据开放共享政策提供切入点与参考思路。 相似文献
166.
[目的 /意义]对在线社区用户承诺影响因素的相关实证研究进行梳理和再分析,以解释影响在线社区用户承诺的一般性因素,为后续研究提供参考。[方法 /过程]运用元分析方法,选取以用户承诺为研究主题、以在线社区为研究情境的文献作为样本文献,归纳和识别在线社区的用户承诺影响因素,并进一步探索影响异质性的调节变量。[结果 /结论 ]显著影响在线社区用户承诺的因素包括系统外部、需求动机及用户感知三个类别的10个变量,与在线社区用户承诺为中度相关关系的有情感依恋、信息性动机、感知娱乐性、信息质量,而社交动机、社会互动、满意度、信任、感知收益、社区认同与用户承诺高度相关。在线社区类型会对情感依恋、社会互动、感知娱乐性等变量与用户承诺之间的关系产生调节。研究结果对未来深入研究和不同情境研究具有借鉴意义,也对在线社区运营具有实践指导作用。 相似文献
167.
结合三峡大学实验教学团队建设的实践,阐述了地方综合性大学物理实验教学团队建设的措施及效果,强调了实验教学团队建设应发挥团队聚合效应,优化团队的学缘结构、年龄结构和职称结构,突出地方综合性大学的特色. 相似文献
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