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101.
FLOSSWorld调查的主体由5部分构成,包括:个人(Private sector)、政府(Government sector)、开源社区参与者(Open Source participants community)、高校管理者(Heigher Education Institutes——Administrators)、高校信息部门主管(Heigher Education Institute——ITManagers)  相似文献   
102.
Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling oftetrapep-tide units Boc-Leu-Pro-Trp-Leu-Ome and Boc-Ile-Ala-Ala-Gly-Ome after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment.Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide--sarcodactylamide.Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz.Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-Ome and Ala-Gly-Ome.Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method.The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis.The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities.Results: Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent.Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp.Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin.Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide.N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine.  相似文献   
103.
The authors examined second grade reading accuracy and fluency and their associations via letter knowledge to phonological and language predictors assessed at 3.5, 4.5, and 5.5 years in children in the Jyv?skyl? Longitudinal Study of Dyslexia. Structural equation modeling showed that a developmentally highly stable factor (early phonological and language processing [EPLP]) behind key dyslexia predictors (i.e., phonological awareness, short-term memory, rapid naming, vocabulary, and pseudoword repetition) could already be identified at 3.5 years. EPLP was significantly associated with reading and spelling accuracy and by age with letter knowledge. However, EPLP had only a minor link with reading fluency, which was additionally explained by early letter knowledge. The results show that reading accuracy is well predicted by early phonological and language skills. Variation in fluent reading skills is not well explained by early skills, suggesting factors other than phonological core skills. Future research is suggested to explore the factors behind the development of fast and accurate decoding skills.  相似文献   
104.
OBJECTIVE: The purpose of this study is to examine processing of facial emotions in a sample of maltreated children showing high rates of post-traumatic stress disorder (PTSD). Maltreatment during childhood has been associated independently with both atypical processing of emotion and the development of PTSD. However, research has provided little evidence indicating how high rates of PTSD might relate to maltreated children's processing of emotions. METHOD: Participants' reaction time and labeling of emotions were measured using a morphed facial emotion identification task. Participants included a diverse sample of maltreated children with and without PTSD and controls ranging in age from 8 to 15 years. Maltreated children had been removed from their homes and placed in state custody following experiences of maltreatment. Diagnoses of PTSD and other disorders were determined through combination of parent, child, and teacher reports. RESULTS: Maltreated children displayed faster reaction times than controls when labeling emotional facial expressions, and this result was most pronounced for fearful faces. Relative to children who were not maltreated, maltreated children both with and without PTSD showed enhanced response times when identifying fearful faces. There was no group difference in labeling of emotions when identifying different facial emotions. CONCLUSIONS: Maltreated children show heightened ability to identify fearful faces, evidenced by faster reaction times relative to controls. This association between maltreatment and atypical processing of emotion is independent of PTSD diagnosis.  相似文献   
105.
两位考古专家一同前去参观金字塔,晚上便住在开罗市郊的一家小旅馆里,一个人留在房间里面写工作日记,另一个人就上街闲逛。他在路边发现有一个老妇人在卖一只黑色的工艺猫,要价1000元。他忽然发现这只猫的两只眼睛竟是两颗大  相似文献   
106.
本文通过对2993名大学生乙型病毒性肝炎表面抗原(HBsAg)的检查发现,处于大学生年龄阶段(18~21岁)的 HBsAg 阳性率男生明显高于女生,这可能与男性较多的不良生活行为有关;农村略高于城市,但无显著差异。  相似文献   
107.
基于国家教育标准的地理教材   总被引:1,自引:0,他引:1  
为进一步增强美国地理教育。我们要做的许多事情之一就是改进教材的质量。其中最主要的三个方面的任务是:(1)开发优良的教材,(2)利用教师联盟的在职培训网络和职前教育计划培训教师使用这种新教材,(3)通过提供强有力的课程指导,特别是将教材与师资培训和基于国家  相似文献   
108.
Old age gives us the privilege to explore, to innovate, to challenge.Dear Friends,This is our twelfth monthly column and the first-year anniversary of our conversation together in the pages of Overseas English. We call this a milestone in English. Is there a Chinese word for it?I would like to begin our column with one of my own poems.  相似文献   
109.
探索重度颅脑损伤合并急性消化道出血救治方法。对 1995~ 2 0 0 0 .12月我院收治的 5 2例重度颅脑损伤合并急性消化道出血的病例进行回顾性分析总结 ,药物治疗效果良好。  相似文献   
110.
教学模式指在一定的教学思想、教育理论和学习理论指导下建立起来的相对稳定的教学结构活动程度。传统的语文教学模式是以教师向学生灌输知识为主的教学模式,把学生变成容纳知识的器物,分数的奴隶,应该的工具。这严重窒息丁学生的创造火花,扼杀了学生的个性,这样的教学模式是不能培养学生的创造性能力的。课堂教学就是要发挥学生的主观能动性、创造性,发挥学生的创新精神和实践能力,在老师的正确引导下,有序地完成学习目标,形成能力,奠定学生扎实的学科基础知识。“读导互动”创新型语丈课堂教学模式,体现的是学生积极主动的探求知识,教师循循善诱,点拨指导,师生互学共进的课堂教学情景,体现的是“授之以渔”的教学原则。体现的是素质教育思想,  相似文献   
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