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171.
国际标准关联标识符(ISLI)标准已经在新闻出版领域取得快速普及与应用。作为信息资源与用户的枢纽中心,图书馆领域与新闻出版业存在天然的联系,了解ISLI标准在新闻出版等领域的实施情况,有利于加速ISLI标准在图书馆行业的应用。文章在梳理ISLI标准的概念、编码体系、实践应用等的基础上,提出优化图书馆数字资源管理系统以支持ISLI编码的识别与管理,积极制定适合于图书馆知识资源和知识元关联的行业标准ISLI/LIB,进行基于ISLI/LIB的知识资源回溯关联、知识元关联服务以及注册中心的构建等应用对策,为用户提供更加精、准、深、专的知识资源和知识服务。  相似文献   
172.
国际博协2007年的博物馆定义,将教育确定为博物馆的首要目的,将征集、保护、研究、传播并展出的对象规定为“人类及人类环境的物质及非物质遗产”。从这一视角分析,科技藏品/展品最重要的价值在于它所承载的自然、科技、历史和文化信息;科技博物馆基于科技藏品/展品的研究、传播与展示设计的基本出发点,是以“科学教育”为目标,揭示其中的“非物质科学文化遗产”,即“物”与“人”的关系。  相似文献   
173.
科技期刊条码中年份码现状调查   总被引:3,自引:0,他引:3  
1 条码中的年份码 条码是由一组按特定规则排列的宽窄不同的线条、空格及相应数据字符组成的符号,是一种信息代码.GB/T16827-1997《中国标准刊号(ISSN部分)条码》[1]已于1998年3月1日起实施.  相似文献   
174.
本文所选取的考辨对象是中唐诗人张莒.本文之立意,是想通过相关的文献考索纠正长期以来人们对其生平认识的谬误,重点在他的籍贯、所任官职与诗赋创作;并附带探讨有关文献编纂的体例问题,以及"慈恩题名"的起源这一文化史公案.  相似文献   
175.
本文从共时和历时方面分析描述了"动词+个+非体词性成分"结构。共时方面,从语义和结构方面认为其中的"非体词性成分"在该结构中作补语,"个"为助词。"动词+个+补语"结构大致产生在元代,并进而从历时方面对其发展作了描述。  相似文献   
176.
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   
177.
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   
178.
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   
179.
Relationship between hyperuricemia and metabolic syndrome   总被引:6,自引:0,他引:6  
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   
180.
[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   
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