民国期刊的版本识别及其客观著录

民国期刊的版本信息在著录时作为次要款目容易被忽略或遗漏,影响了读者对文献的考证和研究。民国期刊版本信息具有客观著录的必要性,编目人员可根据民国期刊的外部特征、内部的文字记录和标记、民国期刊的权威工具书和研究资料来识别一些常见的版本,并利用现有的编目规则对民国期刊版本信息进行客观著录。     

图书馆新型文献检索业务的实践与探析——以国家图书馆的知识产权保护服务为例

当前,我国知识产权纠纷案件明显增多,专利、商标等纠纷诉讼层出不穷。在此类诉讼中,相关证据的采集十分重要。图书馆作为大量收藏出版物的专职机构成为人们收集证据的首选之地。在读者自行收集的资料往往由于缺少第三方监督而被法庭采信较少的情况下,国家图书馆适时推出了由专职工作人员负责全程检索、复印并出具书面报告的新型文献检索复制服务,取得了良好的社会效益。     

基于聚类算法的本体层次关系获取研究

提出利用蚁群聚类方法进行初始聚类,通过K-means聚类算法对初始聚类的结果进一步分层聚类,并结合术语综合相似度计算的方式提取每个类的标签,从而完成术语层次关系的构建。最后抽取部分实验结果,由领域专家对其进行评价,并对结果进行分析。     

知识网络的结构及其知识活动分析

认为知识网络能帮助企业整合资源,获取竞争优势。对以知识链为基本单元的知识网络的内涵、结构及其知识活动进行分析,提出知识网络的构成要素包括网络节点、网络资源、网络活动和支撑环境四个部分,构建出知识网络结构示意图。在此基础上,分析知识网络中的知识活动以及知识活动的基本分析单位之间的知识流动模式。     

Effect of Vitamin E on sP-Selectin Levels in Pre-Eclampsia

P-selectin, a cell adhesion molecule is elevated in many inflammatory conditions including preeclampsia which is characterized by generalized endothelial dysfunction and vasoconstriction presumably due to free radicals or mediators released by defective placentation. Vitamin E has been documented to protect cell membranes from oxidative damage and also decrease platelet aggregation. The role of vitamin E in pre-eclampsia is contradictory and hence the study was undertaken. Soluble P-selectin was measured by ELISA and Vitamin-E levels in plasma was estimated spectrofluorometrically. In our study the effect of supplementation of 400 IU/day of Vitamin E (a-tocopheryl acetate) to patients of pre-eclampsia showed significant decreased levels of soluble P-selectin by 2nd week as compared to patients given placebo (P = 0.005). In this short period of study no direct correlations were observed between Vitamin E or P-selectin levels with blood pressure as well as with proteinuria. Future studies may focus on the effect of a-tocopheryl acetate or the phosphate form of Vitamin-E, recently proposed to be the more active form on other inflammatory markers like IL-6, an important stimuli of P-selectin release in pre-eclampsia.     

Role of Plasma MMP 9 levels in the Pathogenesis of Chronic Pancreatitis

Pancreatic fibrosis is a key pathological feature in the etiology of chronic pancreatitis that leads to obliteration of exocrine and endocrine pancreatic tissues and its replacement by fibrous tissue resulting in clinical manifestations. Matrix metalloproteinase 9 is a member of the MMP family that is also known as gelatinase B, degrades type IV collagen of extracellular matrix and basal membrane. The present study is aimed at evaluating the clinical significance of plasma concentration of MMP-9 in chronic pancreatitis. The samples were obtained from 112 chronic pancreatitis patients and an equal number of age and sex matched healthy controls. MMP-9 levels were quantitatively measured by ELISA assay. Statistical analysis was applied to test the significance of results. The present study revealed a significant increase of plasma MMP 9 levels in chronic pancreatitis patients compared to control subjects. Elevated levels were also observed in all the patient groups compared to control subjects with regard to sex, age, addictions etc. MMP-9 degrades the type IV collagens in normal basement membrane, which in turn activates the pancreatic stellate cells which promote the development of pancreatitic fibrosis. Thus, elevated plasma levels of MMP-9 may act as a susceptibility factor for the development of chronic pancreatitis.     

Organic Acidurias: An Updated Review

Organic acidurias are an important class of inherited metabolic disorders arising due to defect in intermediary metabolic pathways of carbohydrate, amino acids and fatty acid oxidation. This review summarizes the current knowledge about the important organic acidurias in the Indian population. Specifically, diagnosis and principles of treatment of organic acidurias are covered. The salient features of common organic acidurias as well as their prevalence in various parts of the world are reviewed in some detail.     

Profile of Plasma Amino Acid Levels in Rats Exposed to Acute Hypoxic Hypoxia

The effect of acute hypoxic hypoxia on the profile of plasma amino acids in rats was studied and compared to that resulting from acute liver injury induced by giving carbon tetrachloride. In hypoxic rats exposed to 45% air in N₂ for 5 h, the concentrations of branched chain amino acids, including valine, leucine and isoleucine, and aromatic amino acids such as phenylalanine and tyrosine were significantly increased as compared to those in normoxic rats. The ratio of branched-chain to aromatic amino acids (Fischer’s ratio) was significantly decreased. The levels of arginine and citrulline, which are related to the urea cycle, were also depressed. Furthermore, plasma proline level was reduced in hypoxic rats. The activities of plasma marker enzymes for tissue damage remained unchanged during hypoxia, indicating that tissue injury was not induced by exposure to hypoxic conditions. We suggest that the characteristic profile of plasma amino acids and the Fischer ratio are valuable tools for understanding the pathology of acute hypoxia in the absence of systemic tissue damage.