欢迎购阅下列新书

AIM: To investigate the contribution of angiotensin-converting enzyme inhibitor (ACEI) to the regulation of calpain system in infarcted myocardium. METHODS: Rat myocardial infarction (MI) model was established by permanent ligation of the left coronary artery. The treatment with the ACEI inhibitor rampril (1 mg·kg-1·d-1) was started 7 days prior to surgery. On day 1, 3, 7 and 14 after MI, protein levels of calpainⅠ, Ⅱ and calpastatin were determined in left ventricular free wall (LVFW), interventricular septum (IS) and right ventricule. RESULTS: CalpainⅠprotein level was increased in IS 14 d post MI, whereas the protein level of calpainⅡ was maximally increased in LVFW 3 d post MI. Rampril decreased protein up-regulation of calpainⅠ and Ⅱ, and reduced infarct size and interstitial fibrosis. Calpastatin protein expression was not affected by ACEI. CONCLUSIONS: CalpainⅠ is involved in cardiac remodelling in the late and calpainⅡ contributes to cardiac tissue damage in the early phase of MI. The heart protective effect of ACEI may be related to the inhibition of calpain system in the pathogenesis of myocardial infarction.     

绵阳城市广场建设中的特色分析

在调查的基础上，介绍了四川绵阳市的广场，并以铁牛广场为例分析其特色和不足。     

野生朱红硫磺菌驯化栽培研究

营养试验、菌丝体培养和出菇温度试验、培养基酸碱度试验、出菇条件试验结果表明：朱红硫磺菌菌丝体适宜生长的温度范围为15-32℃，最适温度范围为22～28℃；子实体发生的最适温度为16～25℃，气温低于16℃，子实体色泽为淡橙色，16℃以上，子实体呈鲜橙红色；培养料适宜营养C／N为20-26／1；朱红硫磺菌菌丝体适宜酸碱度范围为pH3．0～8．0，最适酸碱度为pH4．0—6．5；朱红硫磺菌的产量与光照条件无关，但光照强度影响子实体的发生时间和色泽；朱红硫磺菌栽培原料广泛，凡栽培木腐菌的培养料均可用于栽培朱红硫磺菌。     

组织培养条件下苹果Ty1-copia类逆转座子的转录活性

研究了苹果基因组中Tyl—copia类逆转座子的转录活性、多样性及其甲基化水平。在培养基MS＋2，4-D2mg／L＋BA0．2mg／L＋NAA0．5mg／L上诱导了1个月的愈伤组织中用RT—PCR方法检测到了270bp的目的条带，而对照、继代组培苗和不含2，4-D的愈伤中均没有目的条带的扩增，说明一定浓度的2，4-D可以诱导苹果中Tyl—copia类逆转座子的表达活性。将目的条带回收、克隆和测序后进行分析：所克隆的21条序列虽都为Tyl-copia类逆转座子逆转录酶保守序列，但存在很大的异质性，21个克隆的核甘酸序列变化范围为196—290bp；翻译成氨基酸后存在缺失、插入、移框和终止密码子突变，7个克隆在氨基酸保守序列‘SLYGLKQ’处有1—2氨基酸位点的突变，说明这些序列对应的逆转录酶多数可能已失去了其原有功能。将21条序列进行聚类分析，除ART20外，其它克隆可聚为3类，并分别与GenBank上某些物种的相应序列同源性很高，表明在不同物种间可能存在逆转座子的横向传递作用。甲基化试验表明苹果基因组内Tyl-copia类逆转座子甲基化水平高。这些都表明Tyl-copia类逆转座子对苹果基因型的多样性及基因组的进化具有重要意义。     

不同化学物质打破葡萄、桃休眠的研究

以保护地栽培的葡萄、桃为试材,对氰氨类、细胞分裂素、赤霉酸和KNO3打破休眠的效果进行了研究。结果表明,1.5%单氰氨、11%石灰氮可明显促使葡萄提前萌芽,提早着色9-10d;50mg/LGA3和100mg/L6-BA对打破休眠基本无效。TDZ与单氰氨混用提高萌芽率的效果最好。在2个葡萄品种上,均没有观察到单氰氨或石灰氮处理对果穗或果实品质性状的不良影响。在华光油桃上,没有观察到化学物质对提早开花或成熟有明显的作用。对葡萄和桃上应用化学物质打破休眠的有关问题进行了讨论。     

高等学校法律地位研究

从考察我国高等学校法律地位的理论与现状入手,分析了高等学校在法律地位上存在的问题,探讨了高等学校的教育权,认为：当前我国高等学校的法律地位主要取决于高校自身所具有的多种社会职能,以及由多种社会职能所必然带来的法律特征.     

母猪卧向行为学的观察

本文通过2个试验对母猪在分娩圈和分娩栏中的卧向行为进行了观察,试验一中, 选择10头大白(Yorkshire)经产母猪作为观察对象,试验二中分别选择10头大白(Yorkshire) 经产母猪和10头长白(Landrace)经产母猪作为观察对象。观察采用瞬时记录方法,每周观察 三次,隔日观察,每天上午、下午各观察一次,每次3 h,每次观察间隔5 min。观察中发现,母猪 卧向以向外为主。分娩栏(四周是栏杆)中的母猪以选择卧向外(向北)为主,其次是卧向内(向 南),卧向左和卧向右最少且差异不显著,上栏前和下栏后差异不显著。分娩圈(四周是墙壁)中 母猪以选择卧向外为主,卧向内最少,卧向左和卧向右差异不显著。长白母猪比大白母猪选择 卧向外的多,妊娠阶段比哺乳阶段选择卧向外的多。     

菌根与植被恢复

菌根不仅可促进植物的营养吸收、生长发育、抗病、抗逆,而且在保持良好的土壤结构、控制水土流失方面具有直接的作用。在我国西北许多地区,菌根菌与植物间的共生关系已被中断,要恢复该地区的植被,治本的方法应是重建植物与菌根菌的共生关系,形成健康的生态系统。文中还提出了菌根技术在植被恢复中的应用策略。     

Selection and amplification of the liver stem cell subset from rat bone marrow cells with a medium containing cholestatic serum in vitro

AIM: To explore the feasibility of direct separat and selective enlargement of the bone marrow-derived liver stem cells (BDLSC) from bone marrow cells with a culture system containing cholestatic serum in vitro. METHODS: Bone marrow cells of rats were cultured with selective media containing 2%, 5%, 7% and 10% cholestatic rat serum, respectively. The BDLSC were then induced to proliferate with the addition of hepatocyte growth factor (HGF) on the firth day. BDLSC were characterized using immunocytochemistry and RT-PCR for lineage markers, glycogen staining and urea synthetic assay for functions 2 weeks later. RESULTS: Bone marrow cells were unble to form colony in the presence of 2% cholestatic serum and apopotosis appeared gradually in 7% or 10% cholestatic serum. The BDLSC survived in the medium containing 5% cholestatic serum while the other types of cells did not. The survival cells proliferated with a high speed during the second week and then formed hepatocyte-like colony-forming units (H-CFU). Cells in the H-CFU expressed the characteristic proteins of fetal hepatocytes. Furthermore, they had glycogen storage and urea synthesis functions, two of the critical features of hepatocytes. CONCLUSION: The selective micro-environment effectively selected BDLSC from the bone marrow cell, and will be a new way to provide an abundant source of donor hepatocytes for clinical cell therapy.     

Effect of mutant β-catenin gene on the proliferation of hepatocytes

AIM:The β-catenin is a key molecule in the Wnt signal pathway, which plays a critical role in normal development and tumorigenesis. However, the mechanisms of the β-catenin on the cell growth control are still not completely defined. The aim of this study was to test the hypothesis that the mutant β-catenin may regulate the hepatocyte proliferation. METHODS: The immortalized murine hepatocyte cell line, AML12, was used for this study. A plasmid that contain mutant β-catenin S33Y was transfected into the AML12 cells and a stable cell line AML12S33Y was established. The cell growth property of this cell line and the parental cell were compared by flow cytometry analysis and direct cell count. The cells were also tested for the ability to form soft agar colonies, and the ability to form tumors in the severe immune deficient mice (SCID). RESULTS:1. The mutant β-catenin containing cell line AML12S33Y has higher proliferating index compared with the parental AML12 cells (P<0.01), suggesting that mutant β-catenin promotes cell growth. 2. The mutant β-catenin cells formed small colonies in soft agar after 4 weeks of culture, but did not generate tumor in SCID mice. CONCLUSION:The mutant β-catenin promotes liver cell growth.