In vitro assessment of gastrointestinal viability of two photosynthetic bacteria, <Emphasis Type="Italic">Rhodopseudomonas palustris</Emphasis> and <Emphasis Type="Italic">Rhodobacter sphaeroides</Emphasis>

The objectives of this study were to assess the potential of two photosynthetic bacteria （PSB）, Rhodopseudomonas palustris HZ0301 and Rhodobacter sphaeroides HZ0302, as probiotics in aquaculture. The viability of HZ0301 and HZ0302 in simulated gastric transit conditions （pH 2.0, pH 3.0 and pH 4.0 gastric juices） and in simulated small intestinal transit conditions （pH 8.0, with or without 0.3% bile salts） was tested. The effects of HZ0301 and HZ0302 on the viability and permeability of intestinal epithelial cell in primary culture of tilapias, Oreochrornis nilotica, were also detected. All the treatments were deter- mined with three replicates. The simulated gastric transit tolerance of HZ0301 and HZ0302 strains was pH-dependent and correspondingly showed lower viability at pH 2.0 after 180 min compared with pH 3.0 and pH 4.0. Both HZ0301 and HZ0302 were tolerant to simulated small intestine transit with or without bile salts in our research. Moreover, there was no significant difference （P〉0.05） among three treatments including the control and the groups treated with HZ0301 or HZ0302 both in intestinal epithelial cell viability and membrane permeability, showing no cell damage. In summary, this study demonstrated that HZ0301 and HZ0302 had high capacity of upper gastrointestinal transit tolerance and were relatively safe for intestinal epithelial cells of tilapias.     

Cell therapy in congestive heart failure

Congestive heart failure （CHF） has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout （necrosis and apoptosis） plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells （CSCs） within the heart divide symmetrically and/or asymmetrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells （BMCs） to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by differentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animat CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, placebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction.     

我国"世界一流大学建设"的高等教育政策评价

为使我国有若干所大学进入世界一流大学的行列,我国政府和大学正在向着这一目标进发,制定了许多政策,采取了许多行动.笔者试图就我国"建设世界一流大学"这一高等教育政策进行评价.     

土司制度下的地方与中央：以佤族聚居区为例

元明清时期,中央王朝通过土司制度实现了对佤族聚居区的间接统治,这一制度的实施,大大加强了中央对地方的控制。同时,中央王朝鉴于势力较大的土司难以控制,于是采取＂众建土司以削其力＂的方式,分而治之;另外,中央王朝利用各民族之间的矛盾,进一步削弱了土司的势力。土司制度的实施曾对佤族社会产生了积极的影响,维护了多民族国家的统一,促进了地方经济的发展和民族融合等。但该制度的封建本质注定了它终将被历史所淘汰。     

四川省民生建设的历史考察及经验启示

自解放至1978年期间,中共四川省委领导全省民生建设取得过巨大的成就,也有过沉痛的曲折,留下了深刻教训;十一届三中全会后,四川省委领导的民生建设飞速发展,成效显著。正反两个方面的经验教训在思想认识、政策路线、建设方法、具体举措和基本原则上启示着四川当前的民生建设。     

女童关系攻击行为及其干预

攻击行为因其伤害性和破坏性受到人们的关注.传统意义上,人们普遍认为攻击行为是一种专属男性的行为,随着攻击研究的深入,人们发现女孩的攻击行为有着与男性不同的表现形式,与身体攻击相比,女孩更偏爱关系攻击.文章从关系攻击行为的表现形式、影响因素及其干预措施三个方面,探讨了女童攻击行为,以促进幼儿的健康发展.     

科学活动中如何指导幼儿进行有效记录

教师在指导幼儿进行有效记录时,首先要正确认识科学活动记录,然后根据活动类型和内容需要来确定是否记录.根据活动目标、进程和幼儿的发展需要确定记录时机,根据幼儿发展情况提供不同的记录工具和材料,根据幼儿的思维特点提出记录要求.根据活动内容和幼儿特点选择恰当的记录方式和组织形式.还应注意组织幼儿对记录过程和结果进行讨论、分享和总结,以充分发挥记录对于幼儿发展的价值.     

现代教育技术与《液压与气压传动》课程整合的实践探索

现代教育技术与课程的整合,对于课程建设与改革、提高教学质量具有重大意义。文章分别从多媒体课件设计,课程网站建设,计算机仿真实验教学这三方面探讨了现代教育技术与《液压与气压传动》课程整合的实践。     

基于上市公司年报分析的图书馆与数据库商博弈思路研究

[目的 /意义]针对图书馆数字资源采购谈判中面临的不合理合约、产品高定价、高涨幅等业内难题,引入上市公司年报分析法来寻求新的博弈思路。[方法 /过程]构建产业链分析、收入-利润指标、竞争力因素分析框架,以Elsevier、中国知网、Clarivate三家数据库商为分析案例,发现竞争力、利润、续订率是数据库商最关注的3个方面,认为图书馆在与数据库商的博弈中同时存在主动性和被动性两方面,在过去的谈判思路中对营业成本与涨价幅度、利润率和参考对象、开放获取与社会责任的认知有一定偏差。[结果 /结论 ]图书馆在开放信息生态下将面临新一轮的资金压力和业务重塑,应从探索零和博弈、重复博弈的竞争性策略,资金适度向国内学术出版商倾斜,寻求媒体关注、法律支持,深化数字出版产品价格相关研究方面应对新的挑战。