DB2用户会话还原分析器的设计与实现

用户套话还原是数据库安全审计的重要手段,可以将用户对数据库的操作历史按照顺序重现.针对现有的DB2审计设施无法直接还原用户会话的问题,在研究DB2审计日志文件的内客和格式的基础上.设计并实现一个用户会话还原分析器.该分析器可以完成审计日志文件的读取和数据库操作记录的还原,并可以分析探作记录中相应字段将同一个会话的操作按顺序关联起来,采用XML格式存储还原后的用户会话结果.     

Antitumor activity of Dioscorea bulbifera L. rhizome in vivo

Antitumor activities of water extract (fraction A), ethanol extract (fraction B), ethyl acetate extract (fraction C), non-ethyl acetate extract (fraction D) and compound diosbulbin B isolated from Dioscorea bulbifera L. (DB) were investigated in vivo in this present study. The results showed that fractions B and C both decreased tumor weight in S180 and H22 tumor cells bearing mice, while fractions A and D had no such effect. Furthermore, fraction C altered the weight of spleen and thymus, and the amounts of total leukocytes, lymphocytes and neutrophils in tumor-bearing mice. Further results showed that compound diosbulbin B demonstrated anti-tumor effects in the dose-dependent manner at the dosage of 2 to 16 mg/kg without significant toxicity in vivo. Furthermore, on the basis of chemical analysis of the above extracts by high-performance liquid chromatography (HPLC) with a diode array detector (DAD), diosbulbin B was found to be the major antitumor bioactive component of DB. These results suggest that DB has potential anti-tumor effects which may be related to influencing the immune system for the first time, and the compound diosbulbin B is the major antitumor component of DB.     

在WEB页中实现动态查询的方法

为了实现对WEB数据库的运态查询，在讨论2种连接WEB数据库方式的基础上，研究了如何对WEB数据库进行快速查找以及不同页面间相同参数传递的方法，给出了相应的ASP程序实现。     

杂交水稻育性基因型初探

本试验通过对两组不完全双列杂交(6×5和4×3)组合的F_2、F_3及B_1等群体的育性分离情况的观察和分析,初步认为杂交水稻育性茎因型因组合不同而不尽一致。有些组合只具有隐性不育基因,另一些组合则既具有隐性不育基因,也具有显性不育基因,显性可育基因对显性不育基因表现出遮盖作用。隐性不育基因数在组合问的变异主要决定于不育系,而显性不育基因数的变异则主要决定于恢复系。作用育性基因数和显性不育基因数与F_1结实率呈显著负相关。本文还提出了根据已知育性基因型求F_2、B_1和F_3等群体的理论不育株率的公式,以及根据各群体的不育株数和样本容量估算其育性基因型的方法。     

水稻几种不同细胞质主要性状的杂种优势效应及其遗传距离

以6组水稻同核异质杂种F_1和亲本为材料,用系×测验系分析法和主成份分析法研究了四种水稻细胞质在19个性状上的杂种优势效应及其遗传距离。系×测验系分析表明,供试胞质对结实率等4个性状的杂种优势仅表现胞质基因效应,对剑叶光合强度等5个性状的杂种优势既表现胞质基因效应,又表现核质互作效应,可育胞质对这些性状多数表现正向胞质基因效应。遗传距离分析表现,雄不育胞质与可育胞质间的遗传差异大于不育胞质间的遗传差异,D胞质、G胞质与野败胞质的遗传差异大于D、G胞质问的遗传差异。以上结果表明,胞质可用来改良作物目标性状,遗传距离分析可作为研究胞质亲缘关系的一种方法。     

几个水稻同核异质雄性不育系的比较研究

本文以三个水稻同核异质雄性不育系为材料,研究水稻雄性不育细胞质在异交习性,花药细胞解剖和同工酶方面表现的效应。结果是:1、不同雄性不育细胞质显著地影响着异交率、外露柱头长度、双柱头外露率、柱头羽部平面积、包粒率和闭颖率。对花时也有明显影响。2、不同雄性不育细胞质对部分花粉母细胞坏死、药壁细胞层之间的联系,和药隔维管束的退化等均有一定影响。但败育类型相同。3、在花粉发育过程中,不同雄不育细胞质明显影响着过氧化物酶同工酶一些强带的活性。本文还对作物雄不育胞质效应的利用,和形态表现,细胞结构及同工酶之间的关系进行了讨论。     

The preventive effect of Bacillus subtilus strain DB9011 against experimental infection with enterotoxcemic Escherichia coli in weaning piglets

Porcine edema disease (ED) is caused by Shiga toxin 2e‐producing Escherichia coli (STEC). Post‐weaned piglets often suffer from ED as a result of intestinal infection with STEC, which causes impaired growth performance and high mortality. Antimicrobial therapy is a curative treatment for piglets infected with STEC, but the emergence of antimicrobial‐resistant STEC has become a serious problem for Japanese pig farmers. Therefore, an alternative strategy other than antimicrobial therapy is needed for the prevention or treatment of ED. In this study, we evaluated the effect of oral administration of Bacillus subtilis DB9011 (DB9011) to prevent the experimental infection of STEC in weaning piglets. Eight 21‐day‐old piglets were divided into two groups: STEC challenge with the basal diet, and STEC challenge with DB9011 supplemented diet. The challenge was carried out when the animals were 25, 26 and 27 days old using STEC contained in capsules resistant against gastric digestion. All pigs were euthanized at 36 days of age. DB9011 improved the symptoms of ED and decreased the number of STEC in the ileal digesta and feces. Accordingly, oral administration of DB9011 in weaned piglets prevents ED through the suppression of the growth of STEC in the ileum.