石墨烯微电子材料潜在应用研究

在硅电子材料即将发展到顶峰时,石墨烯以其优良的导体和半导体性质将成为延续硅材料的主流微电子材料;详述了石墨烯的结构与电学性质,从而说明其作为微电子材料的优势,并列举了在微电子器件构建中已经取得的成果及构建器件的方法,简述了相应石墨烯的制备方法.     

Medicinal uses of inorganic compounds — 2

In the first part of this article, we described medicinal uses of inorganic compounds relating to cancer care, infection and diabetic control, neurological, cardiovascular and inflammatory diseases. This article contains further information on the medicinal uses of inorganic compounds as therapeutic and diagnostic in chelation therapy, as antihypertensive and anti-ulcer agents, metal Superoxide dismutase mimics, metal activation of organic drugs, radiopharmaceuticals, magnetic resonance imaging contrast agents and photodynamic therapy.     

Traditional Chinese medicines and their active ingredients sensitize cancer cells to TRAIL-induced apoptosis

The rapidly developing resistance of cancers to chemotherapy agents and the severe cytotoxicity of such agents to normal cells are major stumbling blocks in current cancer treatments.Most current chemotherapy agents have significant cytotoxicity,which leads to devastating adverse effects and results in a substandard quality of life,including increased daily morbidity and premature mortality.The death receptor of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)can sidestep p53-dependent pathways to induce tumor cell apoptosis without damaging most normal cells.However,various cancer cells can develop resistance to TRAIL-induced apoptosis via different pathways.Therefore,it is critical to find an efficient TRAIL sensitizer to reverse the resistance of tumor cells to TRAIL,and to reinforce TRAIL’s ability to induce tumor cell apoptosis.In recent years,traditional Chinese medicines and their active ingredients have shown great potential to trigger apoptotic cell death in TRAIL-resistant cancer cell lines.This review aims to collate information about Chinese medicines that can effectively reverse the resistance of tumor cells to TRAIL and enhance TRAIL’s ability to induce apoptosis.We explore the therapeutic potential of TRAIL and provide new ideas for the development of TRAIL therapy and the generation of new anticancer drugs for human cancer treatment.This study involved an extensive review of studies obtained from literature searches of electronic databases such as Google Scholar and PubMed."TRAIL sensitize"and"Chinese medicine"were the search keywords.We then isolated newly published studies on the mechanisms of TRAIL-induced apoptosis.The name of each plant was validated using certified databases such as The Plant List.This study indicates that TRAIL can be combined with different Chinese medicine components through intrinsic or extrinsic pathways to promote cancer cell apoptosis.It also demonstrates that the active ingredients of traditional Chinese medicines enhance the sensitivity of cancer cells to TRAIL-mediated apoptosis.This provides useful information regarding traditional Chinese medicine treatment,the development of TRAIL-based therapies,and the treatment of cancer.     

Mesenchymal stem cells as therapeutic agents and in gene delivery for the treatment of glioma

Mesenchymal stem cells (MSCs) are plastic-adherent cells with a characteristic surface phenotype and properties of self-renewal, differentiation, and high proliferative potential. The characteristics of MSCs and their tumortropic capability make them an ideal tool for use in cell-based therapies for cancer, including glioma. These cells can function either through a bystander effect or as a delivery system for genes and drugs. MSCs have been demonstrated to inhibit the growth of glioma and to improve survival following transplantation into the brain. We briefly review the current data regarding the use of MSCs in the treatment of glioma and discuss the potential strategies for development of a more specific and effective therapy.     

Cancer vaccines: The new fight against cancer

The inability of the body’s immune system to differentiate cancer cells from normal cells allows cancer cells to proliferate in an uncontrolled manner. Newer strategies are being researched to overcome this immunological tolerance to cancer. Provoking the body’s immune system to generate vaccines against cancer is emerging as an important type of immunotherapy to treat cancers. These cancer vaccines, which have fewer side effects, and offer great promise. Many such vaccines have been identified and several of them are under clinical trials currently.     

穴状型和Keggin型聚氧钨酸盐结构特征和抗HIV-1、抗癌活性

目的综述无机穴状化合物(NH4)18[NaSb9W21O86]18-,和Keggin型聚氧钨酸盐作为抗人类免疫缺陷病毒-1(HIV-1)和抗癌药物的研究进展。方法根据构效关系对HPA-23和Keggin型聚氧钨酸盐进行体内体外研究。结果标题化合物穿透细胞膜进入细胞中,对HIV-1反转录酶或人体肿瘤有抑制活性。结论:直接揭示其可做为抗癌抗病毒药物。     

DNA alkylation lesion repair: outcomes and implications in cancer chemotherapy

Alkylated DNA lesions, induced by both exogenous chemical agents and endogenous metabolites, represent a major form of DNA damage in cells. The repair of alkylation damage is critical in all cells because such damage is cytotoxic and potentially mutagenic. Alkylation chemotherapy is a major therapeutic modality for many tumors, underscoring the importance of the repair pathways in cancer cells. Several different pathways exist for alkylation repair, including base excision and nucleotide excision repair, direct reversal by methyl-guanine methyltransferase(MGMT), and dealkylation by the AlkB homolog(ALKBH) protein family. However, maintaining a proper balance between these pathways is crucial for the favorable response of an organism to alkylating agents. Here, we summarize the progress in the field of DNA alkylation lesion repair and describe the implications for cancer chemotherapy.     

抗肿瘤阳离子肽：特征、作用机制及展望

恶性肿瘤（癌症）是尚未被攻克的重大疾病之一,主要原因之一是临床上抗肿瘤药物效用不大．具有抗肿瘤活性的阳离子肽（CAP）主要结合肿瘤细胞膜并破坏膜结构,这是通过肽的正电荷与肿瘤细胞膜的负电荷之静电吸引来实现的．与传统化疗药物相比,绕过肿瘤细胞的耐药机制是CAP最突出的优势．本文对抗肿瘤肽的主要结构特征、抗肿瘤效果和抗肿瘤机制（以鲎素为例）进行了综述．作者认为,寻找靶向肿瘤干细胞的CAP对于治愈肿瘤具有特别重要的意义．另外,通过化学改构和新剂型研制,CAP将具有高靶向性和低毒性,给抗肿瘤药物开发提供新的动力．     

英汉颜色词“黑”的比较研究

词汇在语言学习中的作用举足轻重,反映了不同民族不同价值观。有些以人类的基本认识为基础,在学习过程中不容易造成误解,而有些属于文化词语范畴,单单从字面上理解会造成误解。鉴于此,以颜色词"黑"为例,说明对同一色彩词在英汉两种语言表达中存在的异同。     

超顺磁性Fe2O3较Fe3O4用于磁共振胃肠造影剂的优劣研究

用超顺磁性氧化铁制备磁共振造影剂的报道较多,其中的磁粒均为Fe3O4。本文提出了用Fe2O3的可行性,并根据超顺磁性理论推导出两种微粒显示超顺磁现象的临界尺寸理论值分别为24.8nm、31.6 nm,在1.5T磁共振磁场中的临界值为7.1 nm、11.1 nm;根据磁学理论,分析了磁共振造影剂稳定的机理;推导出在磁共振磁场中,两者在造影剂中稳定悬浮的极限尺寸为13.3 nm、14 nm。得出在造影剂中,两者既能稳定悬浮又具有超顺磁性的临界尺寸为7.1 nm、11.1 nm的结论。同时分析了两者用做磁共振胃肠造影剂的优劣点。     

内折香茶菜叶挥发油对人食管癌ECA-109细胞增殖抑制作用的初步研究

利用形态观察法、考马斯亮蓝染色法研究了不同浓度的内折香茶菜叶挥发油对人食道癌ECA-109细胞株的增殖抑制作用．结果显示：当挥发油浓度为0．25μl／mL、0．5μl／mL、1μl／mL、2μl／mL、4μl／mL,ECA-109细胞株生长均受到明显影响．＇-3浓度为0．25μl／mL的内折香茶菜叶挥发油作用细胞24h后,细胞形态开始皱缩、微丝减少,随着浓度加大,细胞逐渐死亡．可见内折香茶菜叶挥发油在体外具有较好的抗癌活性．     

Students' Perceptions of Teaching and Learning: The influence of students' approaches to learning and teachers' approaches to teaching

Nearly 500 secondary students in 24 classes were surveyed and four students in each class interviewed concerning their approaches to learning and perceptions of their classroom environment. While interviewed students with deep approaches to learning generally demonstrated a more sophisticated understanding of the learning opportunities offered to them than did students with surface approaches, teaching strategies also influenced students' perceptions. When teachers focused strongly on actively engaging students and creating a supportive environment, students with both deep and surface approaches focused on student-centred aspects of the class. In contrast, when traditional expository teaching methods were used exclusively, students with deep and surface approaches both focused on transmission and reproduction.     

The Rise of Creative Writing Programmes

Creative writing courses are growing in universities and outside them. Publishers and agents even turn to them now as sources of promise and talent. This article describes a particularly successful MA in creative writing at Goldsmiths College in London and makes a case for the popularity and the usefulness to universities, to aspiring writers and to publishers of such courses.     

The role of community college counselors as validating agents on men of color student success

The purpose of this study was to explore the role of counselors in providing validation for men of color in community colleges. Through protocol writing, 13 counselors from seven community colleges responded to open-ended questions asking them to reflect and describe strategies they employed when advising and counseling men of color. Thematic analysis using a combination of detailed, selective, and wholistic reading approaches, as described by van Manen (1990), was employed to identify themes reflecting different forms of validation. Findings from this study demonstrate the critical role of community college counselors as validating agents in affirming men of color as being capable of college success, helping them build confidence, affirming them as individuals, and providing opportunities for academic and personal development. Implications for practice are discussed.     

基于软件代理支持的学习系统模型构建

文章提出利用一种新型的代理人—过程代理来定制学习支持服务,从而帮助在线学习的个别学习者有效地进行知识建构。首先分析了网络教学系统的现状及其存在的问题;然后构建了一个基于软件代理的学习系统模型,并分析了系统模型中的代理类型及其任务;最后对该模型如何适应个别学习者的问题也进行了相关研究。     

Engagement in Language Policies and Practices with and for Vietnamese Minority Student Youth

Drawing on the recent call for repositioning youth as creative and responsible agents in language and education research (e. g., McCarty & Wyman, 2009) and the notion of engaged ethnography (e.g., Davis & Phyak, 2015), the researcher engaged 16 minority student youth in a remote mountainous province in Vietnam in interrogating the realities of the current language policies (LP) while working actively with them to give rise to effective and responsive LP transformations. Youth’s resistance to the current LP, their critical awareness of their linguistic wealth, and their comprehensive recommendations for LP improvements greatly affirm themselves as resourceful and responsible agents in decision-making and pedagogical revitalizations. This article calls for respecting and recognizing youth’s power, voices, and rights, and invites them to deconstruct educational policies to promote multilingualism and effective educational change. Towards this end, I discuss implications to promote youth engagement in language education policies and practices.     

记忆信息与大脑神经元固有频率的关联性

大脑记忆按事件方式储存,每个树突的固有频率就是记忆事件应有的信息元素。神经元表面成千上万个不同形态的树突树树棘所代表的信息集合就是一个记忆事件的信息储存总和。不同类型的信息内容储存在不同的脑区,同一瞬间储存在不同脑区的事件信息,通过突触机制关联成一个整体事件。记忆的读取遵循电波的谐振原理,通过突触关联的记忆电波可让肌体感知到类同于初始意识体验时曾经有过的意识状态。神经元的生存必须以稳定为前提,神经元不可以成为外来信息的传导介质,所以,颅内神经元群之间的信息交换只能以电波传播为主。     

Study on interleukin-18 gene transfer into human breast cancer cells to prevent tumorigenicity

INTRODUCTIONInterleukin-18(IL-18),originallydescribedasinterferon(IFN)-g-inducingfactor,isan18.3-kDaproinflammatorycytokineproducedbyactivatedmacrophagesanddendriticcells,andplaysanim-portantroleintheTh1response,primarilybasedonitsabilitytoinduceIFN-gproductioninTcellsandNKcells.IL-18inducesproliferationofactivatedTcells,secretionofseveralcytokines,andpartici-patesinbothinnateandacquiredimmunity.TheroleofIL-18inantitumorimmunitywassuggestedinmanystudies.Genetransferofcytokinesisani…     

Study on interleukin-18 gene transfer into human breast cancer cells to prevent tumorigenicity

To study the effect of interleukin-18 gene transfection on the tumorigenesis of breast cancer cell line Bacp37, human breast cancer cell line Bcap37 were transfected with Lipofectamine and selected by G418. The biological expression of rhIL-18 was tested by RT-PCR and ELISA method; nude mice were injected with Bcap37 cell with or without the hIL-18 gene. The hIL-18 cDNA was successfully integrated into Bcap37 cell; 126.3±4.5 pg hIL-18 secreted by one million transduced cells in 24 hours. Nude mice injected with IL-18 gene engineered Bcap37 cell had no tumor growth. These findings indicated that human breast cancer cells were successfully modified by the gene of IL-18 cytokine; the IL-18 gene engineered Bcap37 cells secreted hIL-18 and lost their tumorigenicity. The Bcap37 cells transduced with IL-18 gene may be used as breast cancer vaccine.