Homoharringtonine induces apoptosis of endothelium and down-regulates VEGF expression of K562 cells

Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. How ever, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.     

高等职业教育投资效益的经济学分析

运用经济效益理论，对高等职业教育的投资效益指标进行了分析，并总结出提高高等职业教育投资效益的途径。     

虫媒登革病毒的研究——Ⅱ.登革病毒非结构蛋白NS1的纯化、鉴定及其在临床检测应用

本文从纯化Den2 NS1,Mab入手,自制了Mab亲和层析系统,从感染Den2的细胞膜中,分离提取了天然的Den 2 NS1双体,比较其NGC株与我国地方株(H-87)NS1的理化性质及组成,并对某些重要的生物学性质进行了综合性研究。同时,利用上述研究结果建立了检测DF病人血清特异NS1抗体的新方法,探索其协助临床诊断及研究的可能性。     

The effects of college students’ positive thinking,learning motivation and self-regulation through a self-reflection intervention in Taiwan

This quasi-experimental study examined the effects of a self-reflection intervention on college (college in this article refers to university-level education) students’ positive thinking, learning motivation and self-regulation in Taiwan. One hundred and two college students were selected to participate in an 18-week intervention forming the experimental group (EG) which emphasized providing main lecture, role-play, self-reflection activity, group discussion and group work. Another 179 college students from two other courses were selected as a comparison group. This study showed that supportive, resourced discussion with peers and instructor, self-reflection activities and assignment as a facilitative agent improved the EG students’ positive thinking, learning motivation and self-regulation. In addition, three structural equation models revealed that positive thinking had a strong and direct relation to Taiwanese college students’ pretest learning motivation (β?=?.85) and self-regulation (β?=?.77); learning motivation had a strong and direct relation to students’ pretest positive thinking (β?=?.86) and self-regulation (β?=?.81); and self-regulation had a strong and direct relation to students’ pretest positive thinking (β?=?.83) and learning motivation (β?=?.86). Instructional implications and research recommendations are discussed.     

Investigation of iodine concentration in salt,water and soil along the coast of Zhejiang,China

Objective: We aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not. Methods: We collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean±SEMby Windows SPSS 13.0. Results: (1) The iodine concentration in salt was 27.9±4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6～84.8 μg/L (mean of 11.66 μg/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin'an in mountain area (P＜0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30±2.43 μg/L (n=34), 23.59±27.74 μg/L (n=19)and 12.72±10.72 μg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P＜0.01). (3) Soil iodine value was 0.11～2.93 mg/kg (mean of 1.32 mg/kg).Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content. Conclusion: Iodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution.     

职业教育的本质属性与发展模式选择

进入新世纪，职业教育确立了以服务为宗旨、以就业为导向的发展思路，提出了职业教育办学思想要实现三个转变：一是从计划培养向市场驱动转变；二是从政府直接管理向宏观引导转变；三是从专业学科为本位向职业岗位和就业为本位转变。其最终目的是要求职业教育建立一条有别于普通教育的发展模式。     

休闲英语（64）

编者语：美国是一个热爱体育的民族。体育运动也影响着其英语表达。今天。我们就来看看日常生活中和体育运动相关的一些表达。尤其是和球类相关的表达。     

Analysis of the Tragic Female Images in Eugene O'Neill's Plays

Ruth and Mary are two heroines in Eugene O’Neill’s plays Beyond the Horizon, and Long Day’s Journey into Night. They have some similarities: when they are young, they are beautiful, native and full of hope towards the future life, but both make wrong choices; in the following years, both suffer a lot from these wrong choices, and feel regretful. This paper tries to explore these two tragic female images.     

基于GIS的中小学应急救援指挥系统的设计

以石家庄市为例,以GIS为平台,结合数据库系统,研究开发了中小学应急救援指挥系统.分析了此系统设计的原则、系统架构及特色、系统功能模块和系统的数据库设计,此系统的使用有利于在突发状态下进行通讯指挥,最大程度地预防和减小灾害造成的损失.     

张维屏与江西

张维屏多次赴京考试,并在江西担任过地方官,与江西结下不解之缘,写下不少与江西有关的诗篇。